Composition for pipes containing recycled material

文档序号：231430 发布日期：2021-11-09 浏览：6次中文

阅读说明：本技术 用于管道的含有循环材料的组合物 (Composition for pipes containing recycled material ) 是由弗朗茨·鲁梅尔卢卡·博拉格诺斯特凡·希瑟君特·德雷宁克里斯蒂安·霍尔斯滕西格弗里于 2020-03-16 设计创作，主要内容包括：包含具有低熔体流动速率和相当低的二甲苯冷可溶物含量的多相丙烯共聚物和富含聚丙烯的循环聚合物的组合物。(Composition comprising a heterophasic propylene copolymer with a low melt flow rate and a rather low xylene cold soluble content and a polypropylene rich recycled polymer.)

1. A composition comprising a Recycled Polymer Composition (RPC) and a heterophasic propylene copolymer (HECO), the composition being obtained by blending,

wherein

(a) The Recycled Polymer Composition (RPC) comprises at least 80 wt% recycled polypropylene, based on the weight of the Recycled Polymer Composition (RPC), and

(b) the heterophasic propylene copolymer (HECO) has

(b1) A Xylene Cold Soluble (XCS) fraction determined according ISO 16152 at 25 ℃ in the range of 5.0 to 18 wt.%, and

(b2) melt flow Rate MFR measured according to ISO 1133 in the range of 0.05 to 1.5g/10min₂(230℃/2.16kg)，

Wherein further

(c) The weight ratio [ (HECO)/(RPC) ] of the heterophasic propylene copolymer (HECO) to the Recycled Polymer Composition (RPC) is in the range of 1.1 to 7.0, and

(d) the total weight percentage [ (HECO) + (RPC) ] of the heterophasic propylene copolymer (HECO) to the Recycled Polymer Composition (RPC) is at least 85 wt. -%, based on the weight of the composition.

2. The composition according to claim 1, having a tensile modulus measured according to ISO 527-2 in the range 1100 to 1600MPa and/or a limonene content determined using solid phase microextraction (HS-SPME-GC-MS) in the range 0.5 to 40 mg/kg.

3. Composition according to claim 1 or 2, consisting of the Recycled Polymer Composition (RPC), the heterophasic propylene copolymer (HECO) and optionally Additives (AD), wherein preferably

(a) The total weight percentage [ (HECO) + (RPC) ] of the heterophasic propylene copolymer (HECO) to the Recycled Polymer Composition (RPC) is at least 90 wt. -%, based on the weight of the composition,

and

(b) the remainder up to 100 wt% based on the weight of the composition is Additive (AD).

4. The composition of any of the preceding claims, wherein the composition has a melt flow rate MFR measured according to ISO 1133₂(230 ℃/2.16kg) in the range of 0.05 to 2.0g/10min, preferably the melt flow rate MFR, measured according to ISO 1133, of the Recycled Polymer Composition (RPC)₂(230 ℃/2.16kg) is at least 8.0g/10 min.

5. The composition of any of the preceding claims, wherein the Recycled Polymer Composition (RPC) has

(a)5 to 100mg/kg of limonene content determined using solid phase microextraction (HS-SPME-GC-MS);

and/or

(b)20 to 100mg/kg of total fatty acid content determined using solid phase microextraction (HS-SPME-GC-MS).

6. The composition according to any of the preceding claims, wherein the Recycled Polymer Composition (RPC) further comprises minor amounts of recycled polyethylene, recycled polystyrene, recycled polyamide and an inorganic compound selected from the group consisting of talc, chalk and mixtures thereof,

provided that the amounts are as follows:

(a) the amount of recycled polyethylene does not exceed 15.0 wt. -%, based on the weight of the Recycled Polymer Composition (RPC);

(b) the amount of recycled polystyrene does not exceed 8.00 wt% based on the weight of the Recycled Polymer Composition (RPC);

(c) the amount of recycled polyamide does not exceed 1.50 wt. -%, based on the weight of the Recycled Polymer Composition (RPC); and

(d) the amount of inorganic components selected from the group consisting of talc, chalk and mixtures thereof does not exceed 2.50 wt. -%, based on the weight of the Recycled Polymer Composition (RPC).

7. Composition according to any one of the preceding claims, wherein the heterophasic propylene copolymer (HECO) contains only propylene and ethylene derived units, further of which

(a) Of the heterophasic propylene copolymer (HECO)¹³An ethylene content determined by C-NMR spectroscopy in the range of 3.0 to 8.0% by weight,

and/or

(b) Composition of the Xylene Cold Soluble (XCS) fraction of the heterophasic propylene copolymer (HECO)¹³The ethylene content, determined by C-NMR spectroscopy, is in the range from 30 to 36% by weight.

8. Composition according to any one of the preceding claims, wherein the intrinsic viscosity of the Xylene Cold Soluble (XCS) fraction of the heterophasic propylene copolymer (HECO) determined according to DIN ISO 1628/1 (at 135 ℃ in decalin) is in the range of 2.9 to 4.5dl/g, preferably in the range of 3.2 to 3.8 dl/g.

9. Composition according to any one of the preceding claims, wherein the heterophasic propylene copolymer (HECO) comprises a semi-crystalline propylene homopolymer (PPH) as matrix in which a propylene-ethylene rubber is dispersed as Elastomeric Propylene Copolymer (EPC), wherein preferably the melt flow rate MFR, measured according to ISO 1133, of the semi-crystalline propylene homopolymer (PPH) is₂(230 ℃/2.16kg) is in the range of 0.05 to 1.5g/10 min.

10. The composition of claim 9, wherein the semi-crystalline polypropylene (PPH) comprises two semi-crystalline propylene homopolymer fractions (PPH1) and (PPH2),

wherein

(a) The total weight percentage of the two semi-crystalline propylene homopolymer fractions (PPH1) and (PPH2) ((PPH1) + (PPH2)) is at least 90 wt. -%, more preferably at least 95 wt. -%, still more preferably at least 98 wt. -%, more preferably the semi-crystalline propylene homopolymer (PPH) consists of the two semi-crystalline propylene homopolymer fractions (PPH1) and (PPH2), based on the weight of the semi-crystalline propylene homopolymer (PPH);

and

(b) the weight ratio of the two semi-crystalline propylene homopolymer fractions (PPH1) and (PPH2) ((PPH1)/(PPH2)) is in the range of 0.8 to 1.4, more preferably in the range of 0.9 to 1.3;

wherein further

(c) Melt flow rate MFR, measured according to ISO 1133, of the semi-crystalline propylene homopolymer fraction (PPH1)₂(230 ℃/2.16kg) in the range of 0.01 to 1.0g/10min, more preferably in the range of 0.02 to 0.8g/10min, still more preferably in the range of 0.02 to 0.10g/10 min;

and

(d) melt flow rate MFR, measured according to ISO 1133, of said semi-crystalline propylene homopolymer (PPH)₂(230 ℃/2.16kg) in the range of 0.05 to 2.0g/10min, more preferably in the range of 0.05 to 1.5g/10min, still more preferably in the range of 0.10 to 1.0g/10 min;

preferably provided that the melt flow rate MFR of said semi-crystalline propylene homopolymer (PPH) and said semi-crystalline propylene homopolymer fraction (PPH1)₂Ratio (MFR)₂(PPH)/MFR₂(PPH1)) is at least 3, more preferably in the range of 3 to 10, still more preferably in the range of 4 to 8.

11. The composition according to any of the preceding claims, wherein the heterophasic propylene copolymer (HECO) is alpha nucleated.

12. A process for producing a composition according to any of the preceding claims, wherein the heterophasic propylene copolymer (HECO), the Recycled Polymer Composition (RPC) and the optional Additives (AD) are mixed, preferably melt-mixed, to obtain the composition.

13. A pipe comprising at least 90% by weight of the composition according to any one of the preceding claims 1 to 11, based on the weight of the pipe.

14. Use of a heterophasic propylene copolymer (HECO) as a compatibilizer for a Recycled Polymer Composition (RPC) in pipes, wherein

(a) The heterophasic propylene copolymer (HECO) has

(a1) A Xylene Cold Soluble (XCS) fraction determined according ISO 16152 at 25 ℃ in the range of 5.0 to 18 wt.%, and

(a2) melt flow Rate MFR measured according to ISO 1133 in the range of 0.05 to 1.5g/10min₂(230℃/2.16kg)，

And

(b) the Recycled Polymer Composition (RPC) comprises at least 80 wt% recycled polypropylene, based on the weight of the Recycled Polymer Composition (RPC),

wherein further the heterophasic propylene copolymer (HECO), the Recycled Polymer Composition (RPC) and optionally Additives (AD) are blended to form a composition as part of the pipe,

wherein still further

(c) The weight ratio [ (HECO)/(RPC) ] of the heterophasic propylene copolymer (HECO) to the Recycled Polymer Composition (RPC) is in the range of 1.1 to 7.0, and

15. The use according to claim 14, wherein the pipe comprises at least 90% by weight of the composition.

16. Use according to claim 14 or 15, wherein

(a) The composition is further defined according to any one of claims 2 to 4;

and/or

(b) Further defining the heterophasic propylene copolymer (HECO) according to any of claims 8 to 12; and/or

Technical Field

The present invention relates to a composition comprising a Recycled Polymer Composition (RPC) and a specific heterophasic propylene copolymer (HECO) as a compatibilizer, as well as the manufacture of said composition. The invention further relates to a pipe comprising said composition. Finally, the invention also relates to the use of the specific heterophasic propylene copolymer (HECO) as a compatibilizer for Recycled Polymer Compositions (RPC) in pipes.

Background

Polyolefins, particularly polypropylene, are increasingly being consumed in large quantities in a wide range of applications including packaging for food and other goods, fibers, automotive parts, and a wide variety of finished goods. The reason for this is not only the advantageous price/performance ratio, but also the high versatility and the very wide range of possible modifications of these materials, which makes it possible to tailor the end-use properties in a wide range of applications. Chemical modification, copolymerization, blending, stretching, heat treatment, and combinations of these techniques can convert common grades of polyolefins into valuable products with desirable properties. This has led to a large number of polyolefin materials being produced for use in the consumer sector.

During the past decade, there has been an interest in the sustainability of the environment with plastics and the current number of plastics used. This has led to new legislation on the handling, collection and recycling of polyolefins. In addition, some countries are also striving to increase the percentage of plastic material that is recycled rather than sent to landfills.

In europe, there are approximately 2700 million tons of plastic waste per year; in 2016, 740 million tons were disposed of in a landfill, 1127 million tons were incinerated (to produce energy), and about 850 million tons were recycled. Polypropylene based materials are a particular problem as these materials are widely used for packaging. Given the large amount of waste collected compared to the amount of waste recycled into the stream (only around 30%), there is still a great potential for intelligent recycling of plastic waste streams and mechanical recycling of plastic waste.

Different recycled polymer compositions have appeared on the market today. For example, recycled polymer compositions rich in polypropylene are available on the market. For example, one propylene-rich recycled polymer composition is the commercial product Dipolen PP from mtm plastics. One major drawback of such recycled polymer compositions is that the compositions have a relatively low molecular weight, i.e., have a relatively high melt flow rate, due to the refining process. Thus, such recycled products are generally not suitable for use in the production of pipelines because of the low melt flow rates required for such applications. However, in the field of pipeline technology, not only the melt flow rate of the circulating product is too high to be reused, but also the mechanical properties are insufficient. In general, products produced from such recycled polymers tend to develop crazing and crazing after a short service life. Pipes based on such recycled polymer compositions also have intolerable slow crack properties. Finally, it should be mentioned that the thermal stability is rather low, indicated by a low OIT.

Disclosure of Invention

It is therefore an object of the present invention to provide a composition suitable for pipe applications that meets pipe standards, particularly in the pipe pressure tests shown in the examples section, even though the composition comprises a large amount of recycled polymer composition.

The finding of the present invention is to provide a composition comprising a Recycled Polymer Composition (RPC) comprising at least 80 wt% recycled polypropylene, based on the weight of the Recycled Polymer Composition (RPC), and a heterophasic propylene copolymer (HECO) having a melt flow rate MFR, measured according to ISO 1133₂(230 ℃/2.16kg) does not exceed 1.5g/10min and the amount of Xylene Cold Soluble (XCS) is moderate, i.e. the Xylene Cold Soluble (XCS) fraction does not exceed 18 wt.%. Preferably the heterophasic propylene copolymer (HECO) is nucleated.

The present invention therefore relates to a composition comprising a Recycled Polymer Composition (RPC), a heterophasic propylene copolymer (HECO) and optionally Additives (AD), which composition is obtained by blending, preferably by melt mixing,

wherein

(a) The Recycled Polymer Composition (RPC) comprises at least 80 wt% recycled polypropylene, based on the weight of the Recycled Polymer Composition (RPC), and

(b) the heterophasic propylene copolymer (HECO) has

(b1) A Xylene Cold Soluble (XCS) fraction determined according ISO 16152 at 25 ℃ in the range of 5.0 to 18 wt.%, and

(b2) melt flow Rate MFR measured according to ISO 1133 in the range of 0.05 to 1.5g/10min₂

(230℃/2.16kg)，

Wherein further

(c) The weight ratio [ (HECO)/(RPC) ] of the heterophasic propylene copolymer (HECO) to the Recycled Polymer Composition (RPC) is in the range of 1.1 to 7.0, and

Preferably the heterophasic propylene copolymer (HECO) is alpha nucleated.

Preferably, the limonene (limonene, or limonene) content of the Recycled Polymer Composition (RPC) as determined by solid phase microextraction (HS-SPME-GC-MS) is from 5 to 100 mg/kg.

It is particularly preferred that the composition consists of a Recycled Polymer Composition (RPC), a heterophasic propylene copolymer (HECO) and optionally Additives (AD).

Further preferably, the composition has a tensile modulus measured according to ISO 527-2 in the range 1100 to 1600MPa and/or a melt flow rate MFR measured according to ISO 1133₂(230 ℃/2.16kg) is in the range of 0.05 to 2.0g/10 min.

The composition according to any of the preceding claims, wherein the melt flow rate MFR, measured according to ISO 1133, of the Recycled Polymer Composition (RPC)₂(230 ℃/2.16kg) is at least 8.0g/10 min.

The present invention also relates to a process for producing a composition as defined above and in more detail below, wherein the heterophasic propylene copolymer (HECO) is (melt) mixed with the Recycled Polymer Composition (RPC).

In another aspect, the present invention relates to a pipe comprising at least 90% by weight, based on the weight of the pipe, of a composition as defined above and in more detail below. Further, the present invention also relates to the manufacture of a pipe by (melt) extruding a composition as defined above and in more detail below into a pipe.

Finally, the invention relates to the use of a heterophasic propylene copolymer (HECO) as a compatibilizer for a Recycled Polymer Composition (RPC) in pipes, wherein

(a) The heterophasic propylene copolymer (HECO) has

(a1) A Xylene Cold Soluble (XCS) fraction determined according ISO 16152 at 25 ℃ in the range of 5.0 to 18 wt.%, and

(a2) melt flow Rate MFR measured according to ISO 1133 in the range of 0.05 to 1.5g/10min₂(230℃/2.16kg)，

And

(b) the Recycled Polymer Composition (RPC) comprises at least 85 wt% recycled polypropylene, based on the weight of the Recycled Polymer Composition (RPC),

wherein further the heterophasic propylene copolymer (HECO), the Recycled Polymer Composition (RPC) and optionally Additives (AD) are blended to form a composition as part of a pipe,

wherein still further

(c) The weight ratio [ (HECO)/(RPC) ] of the heterophasic propylene copolymer (HECO) to the Recycled Polymer Composition (RPC) is in the range of 1.1 to 7.0,

and

Other preferred embodiments of the invention are defined in the claims.

Detailed Description

The present invention is defined in more detail below.

Composition comprising a metal oxide and a metal oxide

The composition of the invention must comprise a Recycled Polymer Composition (RPC), a heterophasic propylene copolymer (HECO) and optionally Additives (AD), wherein the composition is obtained by blending, preferably by melt mixing, the components of the composition. Even more preferably, the composition comprising the Recycled Polymer Composition (RPC), the heterophasic propylene copolymer (HECO) and optionally Additives (AD) is obtained by melt mixing the components of the composition in an extruder.

According to the invention, the term "blending" covers both dry mixing and melt mixing of substances, such as melt extrusion. In the case of melt mixing, the substances are preferably fed to the extruder separately, either as a dry blend or by different feeders. In the case of melt mixing, the composition obtained is preferably in the form of pellets.

The Recycled Polymer Composition (RPC) and the heterophasic propylene copolymer (HECO) may first be blended, e.g. melt-mixed, to obtain a mixture (e.g. pellets in case of melt-mixing), which is subsequently mixed, preferably melt-mixed, with the other components of the composition, e.g. the Additives (AD). However, it is preferred to produce the composition in one step, i.e. to add all components in one mixing step. For example, in the case of melt mixing, the components of the composition may be added by one feeder (the components may have been dry-mixed beforehand), or the components may be added to the extruder by different feeders, so as to obtain the composition in the form of preferably pellets.

Thus, if the composition consists of a Recycled Polymer Composition (RPC), a heterophasic propylene copolymer (HECO) and optionally Additives (AD), the two components or all three components (in the presence of the Additives (AD)) are dry-mixed or preferably melt-mixed, more preferably melt-extruded, to obtain the composition in the form of a dry mixture or in the form of pellets in case of melt-mixing or melt-extrusion.

Alternatively, a dry mixture or pellets obtained by melt mixing the Recycled Polymer Composition (RPC) and the heterophasic propylene copolymer (HECO) are first produced, and subsequently the Additive (AD) is mixed into the dry mixture or the melt mixture in a dry mixing manner or preferably in a melt mixing manner, thereby obtaining the composition in the form of a dry blend or a melt mixture, such as pellets.

The total weight percentage [ (HECO) + (RPC) ] of the heterophasic propylene copolymer (HECO) to the Recycled Polymer Composition (RPC) is at least 85 wt. -%, preferably at least 90 wt. -%, more preferably at least 95 wt. -%, based on the weight of the composition.

It is especially preferred that the inventive composition comprises a Recycled Polymer Composition (RPC), a heterophasic propylene copolymer (HECO) and an Additive (AD), wherein the total weight percentage [ (HECO) + (RPC) ] of the heterophasic propylene copolymer (HECO) to the Recycled Polymer Composition (RPC) is at least 85 wt. -%, preferably at least 90 wt. -%, more preferably at least 95 wt. -%, based on the weight of the composition.

It is especially preferred that the inventive composition consists of a Recycled Polymer Composition (RPC), a heterophasic propylene copolymer (HECO) and optionally Additives (AD).

It is therefore particularly preferred that the composition according to the invention consists of

(a) At least 80 wt. -%, more preferably at least 85 wt. -%, still more preferably at least 90 wt. -%, yet more preferably at least 95 wt. -%, based on the weight of the composition, of the heterophasic propylene copolymer (HECO) with the Recycled Polymer Composition (RPC) [ (HECO) + (RPC) ],

and

(b) up to a remainder of 100 wt% of Additives (AD), based on the weight of the composition.

Further, the weight ratio between the heterophasic propylene copolymer (HECO) and the Recycled Polymer Composition (RPC), [ (HECO)/(RPC) ] has to be in the range of 1.1 to 7.0, preferably in the range of 1.2 to 6.5, more preferably in the range of 1.3 to 6.0, still more preferably in the range of 1.4 to 5.5, most preferably in the range of 1.4 to 5.0.

Therefore, preferably not only the weight ratio between the heterophasic propylene copolymer (HECO) and the Recycled Polymer Composition (RPC) has to be taken into account, but also the total amount of both components in the composition according to the invention.

Thus, the composition comprising, preferably consisting of, the heterophasic propylene copolymer (HECO), the Recycled Polymer Composition (RPC) and the optional Additives (AD) is obtained by blending, preferably melt mixing, such as melt extrusion,

wherein

(a) The weight ratio between the heterophasic propylene copolymer (HECO) and the Recycled Polymer Composition (RPC) [ (HECO)/(RPC) ] is in the range of 1.1 to 7.0, preferably in the range of 1.2 to 6.5, and

(b) the total weight percentage [ (HECO)/(RPC) ] of the heterophasic propylene copolymer (HECO) to the Recycled Polymer Composition (RPC) is at least 90 wt. -%, based on the weight of the composition.

More preferably, the composition comprising, preferably consisting of, the heterophasic propylene copolymer (HECO), the Recycled Polymer Composition (RPC) and the optional Additives (AD) is obtained by blending, preferably melt mixing, such as melt extrusion,

wherein

(b) the total weight percentage [ (HECO)/(RPC) ] of the heterophasic propylene copolymer (HECO) to the Recycled Polymer Composition (RPC) is at least 95 wt. -%, based on the weight of the composition.

Even more preferably the composition consisting of the heterophasic propylene copolymer (HECO), the Recycled Polymer Composition (RPC) and the optional Additives (AD) is obtained by blending, preferably melt mixing, such as melt extrusion,

wherein

(a) The weight ratio between the heterophasic propylene copolymer (HECO) and the Recycled Polymer Composition (RPC) [ (HECO)/(RPC) ] is in the range of 1.3 to 6.0, preferably in the range of 1.4 to 5.5, and

(b) the total weight percentage [ (HECO) + (RPC) ] of the heterophasic propylene copolymer (HECO) to the Recycled Polymer Composition (RPC) is at least 95 wt. -%, based on the weight of the composition, the remainder up to 100 wt. -% being the Additive (AD).

Preferably the melt flow rate MFR, measured according to ISO 1133, of the composition of the invention₂(230 ℃/2.16kg) in the range of 0.05 to 2.0g/10minAnd preferably in the range of 0.2 to 1.5g/10 min.

It is furthermore preferred that the tensile modulus of the composition of the invention, measured according to ISO 527-2, is in the range 1100 to 1900MPa, more preferably in the range 1300 to 1700MPa, still more preferably in the range 1100 to 1600 MPa.

In a preferred embodiment, the composition has a limonene content as determined by solid phase microextraction (HS-SPME-GC-MS) of from 0.5 to 40mg/kg, preferably from 0.8 to 30mg/kg, more preferably from 1.0 to 25mg/kg, most preferably from 1.5 to 20 mg/kg. Limonene is commonly found in recycled polyolefin materials and originates from packaging applications in the field of cosmetics, detergents, shampoos and similar products. Thus, due to the presence of the Recycled Polymer Composition (RPC) in the composition, the composition may also contain a detectable amount of limonene.

Recycled Polymer Composition (RPC)

The Recycled Polymer Composition (RPC) of the present invention must be rich in polypropylene.

For the purposes of the present invention, the term "Recycled Polymer Composition (RPC)" is used to denote material recovered from post-consumer and industrial waste, rather than virgin polymer. Post-consumer waste means that the article has completed at least a first use cycle (or life cycle), i.e. has been used for its first purpose; whereas industrial waste refers to manufacturing waste that does not normally reach the consumer.

The term "virgin" refers to materials and/or articles that have been newly produced prior to their first use, which have not been recycled. For example, the heterophasic propylene copolymer (HECO) according to the present invention is a raw material. Many different kinds of recycled polypropylene and many different kinds of recycled polyethylene may be present in the "Recycled Polymer Composition (RPC)". In particular, the polypropylene fraction may comprise: isotactic propylene homopolymer, propylene with ethylene and/or C₄-C₈Random copolymers of alpha-olefins, heterophasic copolymers and mixtures thereof.

Preferably, the polypropylene-rich Recycled Polymer Composition (RPC) of the present invention is obtained from recycled waste by plastic recycling processes known in the art. Such recyclates are commercially available from, for example, Corepla (Italian treasures, responsible for the collection, recovery and Recycling of packaging plastic waste), Resource Plastics Corp (Brampton, ON), Kruschitz GmbH, Plastics and Recycling (AT), Vogt Plastics GmbH (DE), mtm Plastics GmbH (DE), and the like. A non-exhaustive example of a Recycled Polymer Composition (RPC) rich in polypropylene is DIPOLEN PP (mtm Plastics GmbH). It is believed that the present invention is broadly applicable to polypropylene-rich recycled materials or compositions having a high content of recycled polypropylene. The polypropylene-rich Recycled Polymer Composition (RPC) may be in pellet form.

As mentioned above, the recycled polymer composition (RCP) according to the present invention is rich in polypropylene, i.e. the main amount of recycled polymer composition (RCP) is recycled polypropylene. Thus, the recycled polymer composition (RCP) comprises at least 80 wt. -%, preferably at least 83 wt. -%, more preferably at least 85 wt. -% recycled polypropylene based on the weight of the recycled polymer composition (RCP).

The remainder up to 100% by weight, based on the recycled polymer composition (RCP), can be other recycled polymers, such as recycled polyethylene, recycled polystyrene and recycled polyamide, and also inorganic residues, such as talc or chalk. However, to date, the major portion of the recycled polymer composition (RCP) has been recycled polymer. Thus, the amount of recycled polymer, including recycled polypropylene, is at least 90 wt%, more preferably at least 93 wt%, and still more preferably at least 95 wt%, based on the weight of the recycled polymer composition (RCP). Still more preferably, the amount of recycled polymer selected from the group consisting of recycled polypropylene, recycled polyethylene, recycled polystyrene, recycled polyamide and mixtures thereof is at least 90 wt. -%, more preferably at least 93 wt. -%, still more preferably at least 95 wt. -%, based on the weight of the recycled polymer composition (RCP), provided however that the amount of recycled polypropylene is at least 80 wt. -%, more preferably at least 83 wt. -%, more preferably at least 85 wt. -%, based on the weight of the recycled polymer composition (RCP).

Thus, in a preferred embodiment, the Recycled Polymer Composition (RPC) comprises recycled polypropylene, together with a minor amount of at least one recycled polymer selected from the group consisting of recycled polyethylene, recycled polystyrene, recycled polyamide and mixtures thereof, and at least one inorganic compound selected from the group consisting of talc, chalk and mixtures thereof,

provided that the amounts are as follows:

(a) the amount of recycled polypropylene is from 80 to 96 wt%, more preferably from 83 to 95 wt%, still more preferably from 85 to 94 wt%, based on the weight of the Recycled Polymer Composition (RPC);

(b) the amount of recycled polyethylene is not more than 15.0 wt%, more preferably not more than 12.0 wt%, still more preferably not more than 10.0 wt%, based on the weight of the Recycled Polymer Composition (RPC);

(c) the amount of recycled polystyrene is not more than 8.00 wt%, more preferably not more than 7.0 wt%, still more preferably not more than 6.0 wt%, based on the weight of the Recycled Polymer Composition (RPC);

(d) the amount of recycled polyamide is not more than 1.50 wt%, more preferably not more than 1.30 wt%, still more preferably not more than 1.0 wt%, based on the weight of the Recycled Polymer Composition (RPC);

(e) the amount of inorganic components selected from the group consisting of talc, chalk and mixtures thereof does not exceed 2.50 wt. -%, more preferably does not exceed 2.20 wt. -%, still more preferably does not exceed 2.0 wt. -%, based on the weight of the Recycled Polymer Composition (RPC).

Thus, in a more preferred embodiment, the Recycled Polymer Composition (RPC) comprises recycled polypropylene, together with minor amounts of recycled polyethylene, recycled polystyrene, recycled polyamide and an inorganic compound selected from the group consisting of talc, chalk and mixtures thereof,

provided that the amounts are as follows:

Thus, in a particularly preferred embodiment, the Recycled Polymer Composition (RPC) comprises recycled polypropylene, together with minor amounts of recycled polyethylene, recycled polystyrene, recycled polyamide and an inorganic compound selected from the group consisting of talc, chalk and mixtures thereof,

provided that the amounts are as follows:

(b) the amount of recycled polyethylene is more than 0.05 to 15.0 wt. -%, more preferably 1.0 to 12.0 wt. -%, still more preferably 3.0 to 10.0 wt. -%, based on the weight of the Recycled Polymer Composition (RPC);

(c) the amount of recycled polystyrene exceeds 0.05 to 8.00 wt%, more preferably 0.1 to 7.0 wt%, still more preferably 0.5 to 6.0 wt%, based on the weight of the Recycled Polymer Composition (RPC);

(d) the amount of recycled polyamide is more than 0.05 to 1.50 wt%, more preferably 0.08 to 1.30 wt%, still more preferably 0.1 to 1.0 wt%, based on the weight of the Recycled Polymer Composition (RPC);

(e) the amount of inorganic components selected from the group consisting of talc, chalk and mixtures thereof is from 0.05 to 2.50 wt. -%, more preferably from 0.1 to 2.20 wt. -%, still more preferably from 0.5 to 2.0 wt. -%, based on the weight of the Recycled Polymer Composition (RPC).

Preferably, the melt flow rate MFR, measured according to ISO 1133, of the Recycled Polymer Composition (RPC)₂(230 ℃/2.16kg) is at least 8.0g/10min, more preferably in the range of 8.0 to 50g/10min, still more preferably in the range of 10.0 to 20.0g/10 min.

According to the present invention, it is preferred that the limonene content of the Recycled Polymer Composition (RPC) as determined by solid phase microextraction (HS-SPME-GC-MS) is in the range of from 5 to 100mg/kg, preferably from 5 to 80mg/kg, more preferably from 5 to 60mg/kg, most preferably from 5.5 to 50 mg/kg. Limonene is commonly found in recycled polyolefin materials and originates from packaging applications in the field of cosmetics, detergents, shampoos and similar products. Thus, when the composition contains material derived from a domestic waste stream, the Recycled Polymer Composition (RPC) according to the invention contains limonene.

Fatty acid content is yet another indication of the source of recycling of the Recycled Polymer Composition (RPC). According to the invention, it is preferred that the total fatty acid content of the Recycled Polymer Composition (RPC) as determined using solid phase microextraction (HS-SPME-GC-MS) is greater than 0 but not more than 200mg/kg, preferably in the range of from 20 to 200mg/kg, more preferably in the range of from 20 to 100mg/kg, most preferably in the range of from 20 to 50 mg/kg.

Heterophasic propylene copolymer (HECO)

As noted above, recycled polyolefin materials, such as recycled polymer compositions (RCPs), typically comprise a blend of recycled polypropylene, recycled polyethylene, and optionally other recycled polymers, such as recycled polystyrene and/or recycled polyamide. Unfortunately, polypropylene and polyethylene are highly immiscible, resulting in blends with poor adhesion between the phases, coarse morphology, and thus poor mechanical properties. Another disadvantage of recycled polymer compositions, such as recycled polymer compositions (RCPs), is that their melt flow rate is rather high due to degradation during recycling.

Therefore, there is a need for additional components to make such recycled polyolefin materials suitable for specific applications, such as in the present case for pipe applications. Such additional ingredients may act as compatibilizers, even if the different components are miscible.

In the present case, the heterophasic propylene copolymer (HECO) acts as a compatibilizer. According to the invention, a compatibilizer is understood to be a component which makes the recycled polymer composition (RCP) suitable for use in the manufacture of pipes. Thus, the term compatibilizer is understood in a more specific manner. That is to say that the heterophasic propylene copolymer (HECO) not only improves the miscibility of the components present in the composition according to the invention, but also reduces the overall melt flow rate and improves the mechanical properties, in particular in terms of tensile modulus and impact strength at 23 ℃. That is, the heterophasic propylene copolymer (HECO) as a compatibilizer makes it possible to produce pipes containing the recycled polymer composition (RCP) in an amount of at least 10 wt. -%, based on the weight of the pipe, which nevertheless meets the standard requirements. The standard requirement according to the invention is that

(a) An impact resistance according to EN 1411:1996(-10 ℃/4kg) (step method) of at least 1m, and

(b) the internal pressure resistance according to ISO 1167(95 ℃/2.5MPa) is at least 900 hours, preferably at least 1000 hours.

The heterophasic propylene copolymer comprises a matrix, which is a (semi-crystalline) polypropylene, and an elastomeric propylene copolymer. The expression "heterophasic propylene copolymer" or "heterophasic" as used in the present invention means that the elastomeric propylene copolymer is (finely) dispersed in the (semi-crystalline) polypropylene. In other words, the (semi-crystalline) polypropylene constitutes the matrix, wherein the elastomeric propylene copolymer forms inclusions in the matrix, i.e. in the (semi-crystalline) polypropylene. Thus, the matrix contains (finely) dispersed inclusions which are not part of the matrix, and the inclusions contain the elastomeric propylene copolymer. The term "inclusions" according to instant invention preferably means that the matrix and the inclusions form different phases in the heterophasic propylene copolymer (HECO), for example, the inclusions are visible by high resolution microscopy, such as electron microscopy or atomic force microscopy, or by Dynamic Mechanical Thermal Analysis (DMTA). In particular, in DMTA, the presence of a multiphase structure can be determined by the presence of at least two different glass transition temperatures.

The heterophasic propylene copolymer (HECO) according to the present invention has a rather high molecular weight and a rather low rubber amount, i.e. the amount of elastomeric propylene copolymer. Typically, the xylene cold soluble fraction is comparable to the amount of elastomeric propylene copolymer. The heterophasic propylene copolymer (HECO) according to the present invention thus has

(a) A melt flow rate MFR measured according to ISO 1133 in the range of 0.05 to 1.5g/10min, preferably in the range of 0.05 to 1.0g/10min, more preferably in the range of 0.10 to 0.80g/10min₂(230℃/2.16kg)；

And

(b) a Xylene Cold Soluble (XCS) fraction determined according to ISO 16152 at 25 ℃ in the range of 5.0 to 18 wt. -%, preferably in the range of 7.0 to 16 wt. -%, more preferably in the range of 9.0 to 15 wt. -%.

Preferably, the passing of the heterophasic propylene copolymer (HECO) is based on the heterophasic propylene copolymer (HECO)¹³Comonomer content, preferably ethylene and/or C, by C-NMR spectroscopy₄To C₁₂The content of a-olefins, more preferably the ethylene content, is in the range of 2.5 to 10.0 wt.%, more preferably in the range of 3.0 to 8.0 wt.%, still more preferably in the range of 3.5 to 6.5 wt.%.

It is especially preferred that the heterophasic propylene copolymer (HECO) comprises only propylene and ethylene derived units, wherein the propylene is produced by¹³The ethylene content as determined by C-NMR spectroscopy is in the range of 2.5 to 10.0% by weight, more preferably in the range of 3.0 to 8.0% by weight, still more preferably in the range of 3.5 to 6.5% by weight.

It is further preferred that the comonomer content of the Xylene Cold Soluble (XCS) fraction of the heterophasic propylene copolymer (HECO), preferably ethylene and/or C₄To C₁₂The content of a-olefins, more preferably ethylene, is in the range of 28 to 38 wt.%, more preferably in the range of 29 to 37 wt.%, still more preferably in the range of 30 to 36 wt.%.

It is especially preferred that the heterophasic propylene copolymer (HECO) comprises only propylene and ethylene derived units, wherein the passage of Xylene Cold Soluble (XCS) of the heterophasic propylene copolymer (HECO) is¹³Ethylene content of 28 to 38 by C-NMR spectroscopyIn the range of% by weight, more preferably in the range of 29 to 37% by weight, still more preferably in the range of 30 to 36% by weight.

It is further preferred that the Xylene Cold Soluble (XCS) of the heterophasic propylene copolymer (HECO) has a rather high intrinsic viscosity. Thus, the intrinsic viscosity of the Xylene Cold Soluble (XCS) fraction of the heterophasic propylene copolymer (HECO) is preferably in the range of 2.9 to 4.5dl/g, more preferably in the range of 3.0 to 4.2dl/g, still more preferably in the range of 3.2 to 3.8 dl/g.

The heterophasic propylene copolymer (HECO) comprises a matrix, which is a (semi-crystalline) polypropylene (PP), and an Elastomeric Propylene Copolymer (EPC).

The (semicrystalline) polypropylene (PP) is preferably a (semicrystalline) random propylene copolymer (R-PP) or a (semicrystalline) propylene homopolymer (H-PP), the latter being particularly preferred.

The expression "propylene homopolymer" as used in the present invention relates to a polypropylene consisting essentially of propylene units, i.e. more than 99.5 wt%, still more preferably at least 99.7 wt% of propylene units. In a preferred embodiment, only propylene units in the propylene homopolymer are detectable.

If the (semicrystalline) polypropylene (PP) is a (semicrystalline) random propylene copolymer (R-PP), it is preferred that the (semicrystalline) random propylene copolymer (R-PP) comprises monomers copolymerizable with propylene, e.g. comonomers such as ethylene and/or C₄To C₁₂Alpha-olefins, in particular ethylene and/or C₄To C₈Alpha-olefins, such as 1-butene and/or 1-hexene. Preferably, the (semi-crystalline) random propylene copolymer (R-PP) according to the invention comprises, in particular consists of, monomers copolymerizable with propylene, from the group consisting of ethylene, 1-butene and 1-hexene. More specifically, the (semi-crystalline) random propylene copolymer (R-PP) of the invention comprises, in addition to propylene, units derivable from ethylene and/or 1-butene. In a preferred embodiment, the (semi-crystalline) random propylene copolymer (R-PP) comprises only units derivable from propylene and ethylene.

Furthermore, it is preferred that the comonomer content, more preferably the ethylene content, of the (semi-crystalline) random propylene copolymer (R-PP) is in the range of more than 0.6 to 5.0 wt. -%, more preferably in the range of more than 0.6 to 4.0 wt. -%, still more preferably in the range of 0.6 to 3.0 wt. -%.

The term "random" denotes that the comonomers of the (semicrystalline) random propylene copolymer (R-PP) are randomly distributed in the propylene copolymer. The term random is understood in accordance with IUPAC (Glossary of basic tertiary in polymer science; IUPAC criteria 1996).

As described below, the heterophasic propylene copolymer (HECO) is produced by blending a (semi-crystalline) polypropylene (PP) and an Elastomeric Propylene Copolymer (EPC). Preferably, however, the heterophasic propylene copolymer (HECO) is produced in a continuous polymerization process, using reactors configured in series and operated at different reaction conditions. Typically, the (semi-crystalline) polypropylene (PP) is produced in at least one first reactor, preferably two reactors, followed by the production of the Elastomeric Propylene Copolymer (EPC) in at least one second reactor.

Further, the (semi-crystalline) polypropylene (PP), such as the (semi-crystalline) propylene homopolymer (H-PP), of the heterophasic propylene copolymer (HECO) is preferred to have a low melt flow MFR₂(230 ℃/2.16 kg). Thus (semi-crystalline) polypropylene (PP) of a heterophasic propylene copolymer (HECO), such as the melt flow MFR, measured according to ISO 1133, of a (semi-crystalline) propylene homopolymer (H-PP), is preferred₂(230 ℃/2.16kg) is in the range of 0.05 to 2.0g/10min, more preferably in the range of 0.05 to 1.5g/10min, still more preferably in the range of 0.10 to 1.0g/10 min.

Thus, it is preferred that the heterophasic propylene copolymer (HECO) comprises a semi-crystalline propylene homopolymer (PPH) as matrix in which a propylene-ethylene rubber is dispersed as Elastomeric Propylene Copolymer (EPC), wherein the melt flow rate MFR, measured according to ISO 1133, of the semi-crystalline propylene homopolymer (PPH) is preferred₂(230 ℃/2.16kg) is in the range of 0.05 to 2.0g/10min, more preferably in the range of 0.05 to 1.5g/10min, still more preferably in the range of 0.10 to 1.0g/10 min.

The term "semicrystalline" indicates that the polymer is not amorphous. It is therefore preferred that the semi-crystalline polypropylene (PP) according to the invention has a xylene soluble fraction (XCS) of not more than 8 wt. -%, and in case of a (semi-crystalline) propylene homopolymer (H-PP) the xylene soluble fraction (XCS) is even lower, i.e. not more than 5.0 wt. -%, more preferably not more than 4.0 wt. -%.

Thus, it is preferred that the xylene soluble fraction (XCS) of the (semicrystalline) propylene homopolymer (H-PP) is below 5.0 wt. -%, more preferably in the range of 0.5 to 4.5 wt. -%, like in the range of 0.5 to 3.5 wt. -%.

Preferably, the (semi-crystalline) polypropylene (PP) according to the invention has a melting temperature Tm higher than 135 ℃, more preferably higher than 140 ℃. In case of (semi-crystalline) propylene homopolymers (H-PP), the melting temperature Tm is higher than 150 ℃, e.g. at least 156 ℃. The upper range is not more than 168 deg.C, such as not more than 167 deg.C.

Preferably, the (semi-crystalline) polypropylene (PP) comprises two (semi-crystalline) polypropylene fractions (PP1) and (PP2), which differ in their molecular weight. Thus, it is preferred that the (semi-crystalline) polypropylene (PP) comprises two (semi-crystalline) polypropylene fractions (PP1) and (PP2), wherein

(a) The total weight percentage of the two (semi-crystalline) polypropylene fractions (PP1) and (PP2) ((PP1) + (PP2)) based on the (semi-crystalline) polypropylene (PP) is at least 90 wt. -%, more preferably at least 95 wt. -%, still more preferably at least 98 wt. -%,

and

(b) the weight ratio between the (semicrystalline) polypropylene fractions (PP1) and (PP2) ((PP1)/(PP2)) is in the range of 0.8 to 1.4, more preferably in the range of 0.9 to 1.3,

wherein further

(c) Melt flow Rate MFR, measured according to ISO 1133, of the (semi-crystalline) Polypropylene fraction (PP1)₂(230 ℃/2.16kg) in the range of from 0.01 to 1.0g/10min, more preferably in the range of from 0.02 to 0.8g/10min, still more preferably in the range of from 0.02 to 0.10g/10min,

and

(d) melt flow Rate MFR, measured according to ISO 1133, of a (semi-crystalline) Polypropylene (PP)₂(230 ℃/2.16kg) in the range of 0.05 to 2.0g/10min, more preferably in the range of 0.05 to 1.5g/10min, still more preferably in the range of 0.10 to 1.0g/10 min;

preferably provided that (A) isMelt flow Rate MFR of a semi-crystalline polypropylene (PP) with a (semi-crystalline) Polypropylene fraction (PP1)₂Ratio (MFR)₂(PP)/MFR₂(PP1)) is at least 3, more preferably in the range of 3 to 10, still more preferably in the range of 4 to 8.

Preferably, the (semicrystalline) polypropylene fractions (PP1) and (PP2) are semicrystalline propylene homopolymer fractions (PPH1) and (PPH2), and the (semicrystalline) polypropylene (PP) is a semicrystalline propylene homopolymer (PPH).

The second component of the heterophasic propylene copolymer (HECO) is an Elastomeric Propylene Copolymer (EPC).

Preferably, the Elastomeric Propylene Copolymer (EPC) comprises units derived from

Propylene and

ethylene and/or C₄To C₁₂An alpha-olefin.

The Elastomeric Propylene Copolymer (EPC) comprises a copolymer of (i) propylene and (ii) ethylene and/or at least one other C₄To C₁₂Alpha-olefins, e.g. C₄To C₁₀Units derived from an alpha-olefin, more preferably units which may consist of, preferably consist of, (i) propylene and (ii) ethylene and/or at least one further alpha-olefin selected from the group consisting of 1-butene, 1-pentene, 1-hexene, 1-heptene and 1-octene.

Thus, the Elastomeric Propylene Copolymer (EPC) preferably comprises at least units derivable from propylene and ethylene and may comprise further units derivable from another alpha-olefin as defined in the previous paragraph. However, it is particularly preferred that the Elastomeric Propylene Copolymer (EPC) comprises only units derivable from propylene and ethylene. It is therefore particularly preferred that the Elastomeric Propylene Copolymer (EPC) is an ethylene-propylene rubber (EPR), otherwise known as ethylene propylene rubber.

In the present invention, the content of units derivable from monomer units other than propylene, in particular ethylene, in the Elastomeric Propylene Copolymer (EPC) is largely identical to the content of units derivable from monomer units other than propylene, in particular ethylene, detectable in the Xylene Cold Soluble (XCS) fraction. Thus, ethylene and/or C of Elastomeric Propylene Copolymer (EPC)₄To C₁₂Alpha-olefin contentSuch as ethylene content, in the range of 28 to 38 wt.%, more preferably in the range of 29 to 37 wt.%, still more preferably in the range of 30 to 36 wt.%. It is particularly preferred that the Elastomeric Propylene Copolymer (EPC) is a propylene-ethylene rubber (EPR) having an ethylene content in the range of from 28 to 38% by weight, more preferably in the range of from 29 to 37% by weight, still more preferably in the range of from 30 to 36% by weight.

The heterophasic propylene copolymer (HECO) may contain typical additives known in the art, such as antioxidants or process additives. It is especially preferred that the heterophasic propylene copolymer (HECO) is alpha-nucleated, i.e. contains an alpha-nucleating agent.

Preferably the alpha-nucleating agent is selected from the group consisting of:

(i) salts of monocarboxylic and polycarboxylic acids, e.g. sodium benzoate or aluminium tert-butylbenzoate, and

(ii) dibenzylidene sorbitol (e.g., 1,3:2,4 dibenzylidene sorbitol) and C₁-C₈Alkyl-substituted dibenzylidene sorbitol derivatives, e.g. methyldibenzylidene sorbitol, ethyldibenzylidene sorbitol or dimethyldibenzylidene sorbitol (e.g. 1,3:2, 4-bis (methylbenzylidene) sorbitol), or substituted nonanol (nonitol) derivatives, e.g. 1,2,3, -trideoxy-4, 6:5, 7-bis-O- [ (4-propylphenyl) methylene]-a nonanol, and

(iii) salts of diesters of phosphoric acid, e.g. sodium 2,2 '-methylenebis (4, 6-di-tert-butylphenyl) phosphate or aluminum hydroxy bis [2,2' -methylene-bis (4, 6-di-tert-butylphenyl) phosphate ], or aluminum hydroxy-bis [2,2'-methylene-bis (4,6-di-t-butylphenyl) phosphate ], or basic aluminum 2,2' -methylene-bis (4, 6-di-tert-butylphenyl) phosphate ], and

(iv) polymers of vinylcycloalkanes or vinylalkane polymers, and

(v) mixtures thereof.

Preferably the alpha-nucleating agent comprised in the heterophasic propylene copolymer (HECO) is a vinylcycloalkane polymer and/or a vinylcycloalkane polymer, more preferably a vinylcycloalkane polymer, such as Vinylcyclohexane (VCH) polymer. Vinylcyclohexane (VCH) polymers are particularly preferred as alpha-nucleating agents. Preferably, the amount of vinylcycloalkane polymer (e.g. Vinylcyclohexane (VCH) polymer) and/or vinylalkane polymer, more preferably Vinylcyclohexane (VCH) polymer, in the heterophasic propylene copolymer (HECO) is not more than 500ppm, preferably not more than 200ppm, more preferably not more than 100ppm, such as in the range of 0.1 to 500ppm, preferably in the range of 0.5 to 200 ppm. Furthermore, it is understood that the vinylcycloalkane polymer and/or the vinylalkane polymer are incorporated into the composition by BNT techniques, as described in more detail below.

Such nucleating agents are commercially available and are described, for example, in "plastics Additives Handbook", 5 th edition, published in Hans Zweifel 2001 (pages 967 to 990).

As mentioned above, the heterophasic propylene copolymer (HECO) may be produced by blending a (semi-crystalline) polypropylene (PP) with an Elastomeric Propylene Copolymer (EPC). Preferably, however, the heterophasic propylene copolymer (HECO) is produced in a continuous step process, using reactors configured in series and operated at different reaction conditions. Thus, each fraction produced in a particular reactor may have its own molecular weight distribution and/or comonomer content distribution. The heterophasic propylene copolymer (HECO) according to the present invention is preferably produced in a continuous polymerization process known in the art, i.e. in a multistage process, wherein the (semi-crystalline) polypropylene (PP) is produced in at least one slurry reactor, preferably in one slurry reactor and optionally in a subsequent gas phase reactor, followed by the production of the Elastomeric Propylene Copolymer (EPC) in at least one, i.e. one or two gas phase reactors.

Thus, the heterophasic propylene copolymer (HECO) is preferably produced in a continuous polymerization process comprising the following steps

(a) In a first reactor (R1), propylene and optionally at least one ethylene and/or C₄To C₁₂Polymerizing alpha-olefins, preferably polymerizing propylene only, obtaining a first polypropylene fraction (PP1) of (semi-crystalline) polypropylene (PP), preferably said first polypropylene fraction (PP1) is a propylene homopolymer fraction (PPH1),

(b) transferring a first polypropylene fraction (PP1), such as a propylene homopolymer fraction (PPH1), to a second reactor (R2),

(c) in a second reactor (R2) and in the presence of the first polypropylene fraction (PP1), such as a propylene homopolymer fraction (PPH1), propylene and optionally at least one ethylene and/or C₄To C₁₂Polymerizing an alpha-olefin, preferably polymerizing only propylene, thereby obtaining a second polypropylene fraction (PP1), preferably the second polypropylene fraction (PP2) being a second propylene homopolymer fraction (PPH2), the first polypropylene fraction (PP1) and the second polypropylene fraction (PP2) forming a matrix of a (semi-crystalline) polypropylene (PP), preferably a propylene Homopolymer (HPP), i.e. a heterophasic propylene copolymer (HECO),

(d) transferring the (semi-crystalline) polypropylene (PP) of step (c), such as propylene Homopolymer (HPP), to a third reactor (R3),

(e) in a third reactor (R3) and in the presence of the (semi-crystalline) polypropylene (PP), such as propylene Homopolymer (HPP), obtained in step (C), propylene and at least one ethylene and/or C₄To C₁₂Polymerizing an alpha-olefin, thereby obtaining an Elastomeric Propylene Copolymer (EPC); elastomeric Propylene Copolymers (EPC) dispersed in (semi-crystalline) polypropylene (PP), such as propylene Homopolymers (HPP); the (semi-crystalline) polypropylene (PP) and the Elastomeric Propylene Copolymer (EPC) form a heterophasic propylene copolymer (HECO).

Of course, a second polypropylene fraction (PP2) may be produced in the first reactor (R1) and a first polypropylene fraction (PP1) may be obtained in the second reactor (R2). Preferably, the monomer flashes off between the second reactor (R2) and the third reactor (R3).

The term "continuous polymerization process" indicates that the heterophasic propylene copolymer (HECO) is produced in at least two, such as three, reactors in series. Thus, the process comprises at least a first reactor (R1) and a second reactor (R2), more preferably a first reactor (R1), a second reactor (R2) and a third reactor (R3). The term "polymerization reactor" shall indicate that the main polymerization takes place. Thus, in case the process consists of three polymerization reactors, this definition does not exclude the option that the whole process comprises a prepolymerization step, e.g. in a prepolymerization reactor. The term "consisting of … …" is merely a closed expression for the main polymerization reactor.

The first reactor (R1) is preferably a Slurry Reactor (SR) and may be any continuous or simple stirred batch tank reactor or loop reactor operating in bulk or slurry mode. Bulk means polymerization in a reaction medium containing at least 60% (w/w) of monomer.

According to the present invention, the Slurry Reactor (SR) is preferably a (bulk) Loop Reactor (LR).

The second reactor (R2) may be a slurry reactor like the first reactor, such as a loop reactor, or alternatively a Gas Phase Reactor (GPR).

The third reactor (R3) is preferably a Gas Phase Reactor (GPR).

Such Gas Phase Reactor (GPR) may be any mechanically mixed or fluidized bed reactor.

Preferably, the Gas Phase Reactor (GPR) comprises a mechanically stirred fluidized bed reactor with a gas velocity of at least 0.2 m/s. It will therefore be understood that the gas phase reactor is a fluidized bed type reactor, preferably with a mechanical stirrer.

Thus, in a preferred embodiment, the first reactor (R1) is a Slurry Reactor (SR), such as a Loop Reactor (LR), while the second reactor (R2) and the third reactor (R3) are Gas Phase Reactors (GPR). Thus, for the present process at least three, preferably three polymerization reactors are used in series, i.e. one Slurry Reactor (SR) (e.g. one Loop Reactor (LR)), one first gas phase reactor (GPR-1) and one second gas phase reactor (GPR-2). If desired, a prepolymerization reactor is placed before the Slurry Reactor (SR).

In another preferred embodiment, the first reactor (R1) and the second reactor (R2) are Slurry Reactors (SR), such as Loop Reactors (LR), and the third reactor (R3) is a Gas Phase Reactor (GPR). Thus, for the present process at least three, preferably three polymerization reactors in series are used, i.e. two Slurry Reactors (SR), such as two Loop Reactors (LR), and one gas phase reactor (GPR-1). If desired, a prepolymerization reactor is placed before the first Slurry Reactor (SR).

A preferred multi-stage process is a "loop-gas phase" process, such as that developed by Borealis A/S, Denmark (referred to asTechniques), for example as described in the patent literature, for example as described in EP 0887379, WO 92/12182, WO 2004/000899, WO 2004/111095, WO 99/24478, WO 99/24479 or WO 00/68315.

More suitable slurry-gas phase processes are BasellAnd (5) processing.

Preferably, in the present process for producing the heterophasic propylene copolymer (HECO) as defined above, the conditions of the first reactor (Rl) of step (a), i.e. the Slurry Reactor (SR), such as the Loop Reactor (LR), may be as follows:

-a temperature in the range of 50 ℃ to 110 ℃, preferably between 60 ℃ and 100 ℃, more preferably between 68 ℃ and 95 ℃;

-a pressure in the range of 20 to 80 bar, preferably between 40 and 70 bar.

Hydrogen may be added for controlling the molar mass in a manner known per se.

Subsequently, the reaction mixture from step (a) is transferred to a second reactor (R2), i.e. a gas phase reactor (GPR-1), i.e. to step (c), wherein the preferred conditions for step (c) are as follows:

-a temperature in the range of 50 ℃ to 130 ℃, preferably between 60 ℃ and 100 ℃;

-a pressure in the range of 5 to 50 bar, preferably between 15 and 35 bar.

Hydrogen may be added for controlling the molar mass in a manner known per se.

The conditions in the third reactor (R3), preferably the second gas phase reactor (GPR-2), are similar to those in the second reactor (R2).

The residence time in the three reaction zones can vary.

In one embodiment of the process, the residence time of the heterophasic propylene copolymer (HECO) in the bulk reactor, such as the loop reactor, is in the range of 0.1 to 2.5 hours, such as in the range of 0.15 to 1.5 hours, and the residence time in the gas phase reactor is typically 0.2 to 6.0 hours, such as 0.5 to 4.0 hours.

If desired, the polymerization can be carried out under supercritical conditions in a known manner in the first reactor (R1), i.e.in a Slurry Reactor (SR), e.g.in a Loop Reactor (LR), and/or in condensed-state mode in a gas-phase reactor (GPR).

Preferably, the process further comprises a prepolymerization with a catalyst system comprising a ziegler-natta procatalyst, an external donor and optionally a cocatalyst, as described in detail below.

In a preferred embodiment, the prepolymerization is carried out as a bulk slurry polymerization in liquid propylene, i.e. the liquid phase comprises mainly propylene in which minor amounts of other reactants and optionally inert components are dissolved.

The prepolymerization is usually carried out at a temperature of 10 to 60 ℃, preferably 15 to 50 ℃, more preferably 20 to 45 ℃.

The pressure in the prepolymerization reactor is not critical but must be high enough to maintain the reaction mixture in the liquid phase. Thus, the pressure may be 20 to 100 bar, for example 30 to 70 bar.

The catalyst components are preferably introduced in their entirety into the prepolymerization step.

However, in case the solid catalyst component (i) and the cocatalyst (ii) may be fed separately, it is possible to introduce only a portion of the cocatalyst into the prepolymerization stage and the remaining portion into the subsequent polymerization stage. Also in this case, it is necessary to introduce a large amount of co-catalyst in the prepolymerization stage to obtain sufficient polymerization therein.

Other components may also be added during the prepolymerization stage. Thus, hydrogen may be added during the prepolymerization stage to control the molecular weight of the prepolymer, as is known in the art. Further, an antistatic additive may be used to prevent particles from adhering to each other or to the reactor wall.

Precise control of the prepolymerization conditions and the reaction parameters is within the skill of the art.

According to the present invention, a heterophasic propylene copolymer (HECO) is obtained by a multistage polymerization process as described above in the presence of a catalyst system comprising as component (i) a ziegler-natta procatalyst containing a transesterification product of a lower alcohol and a phthalate.

The procatalyst may be a "non-phthalic" ziegler-natta procatalyst or a "phthalic" ziegler-natta procatalyst. Described first is a "non-phthalic" Ziegler-Natta procatalyst, followed by a "phthalic" Ziegler-Natta procatalyst.

The "non-phthalic" ziegler-natta procatalyst comprises an IUPAC group 4 to 6 transition metal compound (TC), such as titanium, a group 2 Metal Compound (MC), such as magnesium, and an Internal Donor (ID) which is a non-phthalic compound, preferably a non-phthalate ester, still more preferably a diester of a non-phthalic dicarboxylic acid, as described in more detail below. Thus, the "non-phthalic" Ziegler-Natta procatalyst is completely free of undesirable phthalic compounds. Furthermore, the "non-phthalic" Ziegler-Natta procatalyst does not contain any externally supported material, such as silica or MgCl₂However, the catalyst is of the self-supported type.

The "non-phthalic" Ziegler-Natta procatalyst may be further defined by the manner of obtainment. Thus, the "non-phthalic" Ziegler-Natta procatalyst is preferably obtained by a process comprising the following steps

a₁) Providing a solution of at least one group 2 metal alkoxide (Ax), the group 2 metal alkoxide (Ax) being the reaction product of a group 2 Metal Compound (MC) and an alcohol (a), optionally in an organic liquid reaction medium, the alcohol (a) including at least one ether moiety in addition to a hydroxyl moiety;

a₂) A solution of at least one group 2 metal alkoxide (Ax'), a group 2 metalAlkoxy compounds (Ax') are the reaction products of a group 2 Metal Compound (MC) with an alcohol mixture of an alcohol (a) and a monohydric alcohol of the formula ROH (B), optionally in an organic liquid reaction medium;

a₃) Providing a solution of a mixture of a group 2 alkoxide (Ax) and a group 2 metal alkoxide (Bx), the group 2 metal alkoxide (Bx) being the reaction product of a group 2 Metal Compound (MC) and a monohydric alcohol (B), optionally in an organic liquid reaction medium; and

b) adding the solution from step a) to at least one compound (TC) of a group 4 to 6 transition metal, and

c) the particles of the solid catalyst component are obtained,

and adding a non-phthalic internal electron donor (ID) at any step prior to step c).

The Internal Donor (ID) or a precursor thereof is preferably added to the solution of step a).

According to the above procedure, the "non-phthalic" Ziegler-Natta procatalyst can be obtained by precipitation or by emulsion (liquid/liquid two-phase system) -solidification, depending on the physical conditions, in particular the temperature used in steps b) and c).

In both processes (precipitation or emulsion-solidification), the catalyst chemistry is the same.

In the precipitation process, the combination of the solution of step a) with the at least one transition metal compound (TC) in step b) is carried out and the entire reaction mixture is kept at least at a temperature in the range of 50 ℃, more preferably in the range of 55 to 110 ℃, more preferably in the range of 70 to 100 ℃ to ensure complete precipitation of the catalyst component in the form of solid particles (step c).

In the emulsion-curing process, in step b), the solution of step a) is added to at least one transition metal compound (TC) generally at a relatively low temperature, for example from-10 to less than 50 ℃, preferably from-5 to 30 ℃. During the stirring of the emulsion, the temperature is generally maintained at-10 to less than 40 ℃ and preferably from-5 to 30 ℃. The dispersed phase droplets of the emulsion form the active "non-phthalic" ziegler-natta procatalyst component. The solidification of the droplets (step c) is suitably carried out by heating the emulsion to a temperature of from 70 to 150 c, preferably from 80 to 110 c.

The present invention preferably employs an emulsion-solidification process prepared "non-phthalic" ziegler-natta procatalyst.

In a preferred embodiment, a) is used in step a)₂) Or a₃) I.e. a solution of (Ax') or a mixture of (Ax) and (Bx).

Preferably, the group 2 Metal (MC) is magnesium.

The magnesium alkoxide compounds (Ax), (Ax') and (Bx) may be prepared in situ in the first step of the catalyst preparation process (step a)) by reacting the magnesium compound with one or more of the alcohols described above, or the magnesium alkoxide compounds may be separately prepared magnesium alkoxide compounds, or they may even be commercially available as ready-made magnesium alkoxide compounds and used as such in the catalyst preparation process of the present invention.

Illustrative examples of alcohols (A) are monoethers of glycols (glycol monoethers). Preferably, the alcohol (A) is C₂To C₄Glycol monoethers, wherein the ether moiety contains from 2 to 18 carbon atoms, preferably from 4 to 12 carbon atoms. Preferred examples are 2- (2-ethylhexyloxy) ethanol, 2-butoxyethanol, 2-hexyloxyethanol and 1, 3-propanediol monobutyl ether, 3-butoxy-2-propanol, 2- (2-ethylhexyloxy) ethanol and 1, 3-propanediol monobutyl ether, 3-butoxy-2-propanol being particularly preferred.

An exemplary monohydric alcohol (B) has the formula ROH, wherein R is a straight or branched chain C₆-C₁₀An alkyl residue. The most preferred monohydric alcohol is 2-ethyl-1-hexanol or octanol.

Preference is given to using mixtures of Mg alkoxylates (Ax) and (Bx) or mixtures of alcohols (A) and (B), respectively, with the molar ratio of Bx: ax or B: the molar ratio of A is 8: 1 to 2: 1, more preferably 5:1 to 3: 1.

the magnesium alkoxide compound may be the reaction product of one or more alcohols as defined above and a magnesium compound selected from the group consisting of dialkyl magnesium, alkyl alkoxy magnesium, dialkoxy magnesium, alkoxy magnesium halide and alkyl magnesium halide. Alkane (I) and its preparation methodThe radicals may be similar or different C₁-C₂₀Alkyl, preferably C₂-C₁₀An alkyl group. Typical alkyl-alkoxy magnesium compounds, when used, are ethylbutoxymagnesium, butylpentyloxygagnesium, octylbutoxymagnesium and octyloctyloxymagnesium. Preferably, a magnesium dialkyl is used. The most preferred magnesium dialkyl is butyl octyl magnesium or butyl ethyl magnesium.

It is also possible that the magnesium alkoxide compound can be reacted, in addition to the alcohol (A) and the alcohol (B), with a compound of the formula R' (OH)_mTo obtain the magnesium alkoxide compound. Preferred polyols, if used, are alcohols, wherein R' is a linear, cyclic or branched C₂To C₁₀A hydrocarbon residue, and m is an integer from 2 to 6.

Thus, the magnesium alkoxide compound of step a) is selected from the group consisting of magnesium dialkoxide, diaryloxy magnesium, alkoxymagnesium halide, aryloxymagnesium halide, alkylalkoxymagnesium, arylalkoxymagnesium and alkylaryloxymagnesium. Furthermore, mixtures of magnesium dihalides and dialkoxy magnesium may be used.

The solvent employed for the preparation of the present catalyst may be selected from aromatic and aliphatic linear, branched and cyclic hydrocarbons or mixtures thereof having from 5 to 20 carbon atoms, more preferably from 5 to 12 carbon atoms. Suitable solvents include benzene, toluene, cumene, xylene, pentane, hexane, heptane, octane, and nonane. Hexane and pentane are particularly preferred.

The magnesium compound is generally provided as a 10 to 50% by weight solution in the above-mentioned solvent. Typical commercially available magnesium compounds, especially dialkylmagnesium solutions, are 20-40% by weight in toluene or heptane.

The reaction for preparing the magnesium alkoxide compound may be carried out at a temperature of 40 to 70 ℃. The most suitable temperature is selected according to the magnesium compound and the alcohol or alcohols used.

The transition metal compound of groups 4 to 6 is preferably a titanium compound, most preferably a titanium halide, such as TiCl₄。

The Internal Donor (ID) used for the preparation of the catalyst used according to the invention is preferably selected from the group consisting of (di) esters of non-phthalic carboxylic (di) acids, 1, 3-diethers, derivatives and mixtures thereof. Particularly preferred donors are diesters of monounsaturated dicarboxylic acids, in particular esters belonging to the group comprising malonates, maleates, succinates, citraconates, glutarates, cyclohexen-1, 2-dicarboxylates and benzoates, and any derivatives and/or mixtures thereof. Preferred examples are substituted maleates and citraconates, with citraconates being most preferred.

In the emulsion process, a two-phase liquid-liquid system may be formed by: simple stirring and optionally the addition of (further) solvents and additives, such as Turbulence Minimizing Agents (TMA) and/or emulsifiers and/or emulsion stabilizers, such as surfactants, which are used in a manner known in the art to promote the formation of an emulsion and/or to stabilize an emulsion. Preferably, the surfactant is an acrylic or methacrylic polymer. Particularly preferred is unbranched C₁₂To C₂₀(meth) acrylates, such as poly (hexadecyl) methacrylate and poly (octadecyl) methacrylate and mixtures thereof. If a Turbulence Minimizing Agent (TMA) is used, it is preferably an alpha-olefin polymer selected from alpha-olefin monomers having from 6 to 20 carbon atoms, such as polyoctene, polynonane, polydecene, polyundecene or polydodecene or a mixture thereof. Most preferred is polydecene.

The solid particulate product obtained by precipitation or emulsion-solidification is washed at least once, preferably at least twice, most preferably at least three times with an aromatic and/or aliphatic hydrocarbon, preferably with toluene, heptane or pentane. The catalyst may be further dried, such as by evaporation or flushing with nitrogen, or it may be slurried into an oily liquid without any drying step.

The resulting "non-phthalic" Ziegler-Natta procatalyst is desirably in particulate form, typically having an average particle size in the range of from 5 to 200 μm, preferably from 10 to 100 μm. Compact particles, low porosity and surface area less than 20g/m²More preferably less than 10g/m². In general, the amount of Ti used in the catalyst component is from 1 to 6% by weight, the amount of Mg used is from 10 to 20% by weight and the amount of donor used is from 10 to 40% by weight.

Detailed descriptions of the preparation of the catalysts are disclosed in WO 2012/007430, EP 2610271 and EP 2610272, which are incorporated herein by reference.

"phthalic acid" Ziegler-Natta procatalysts prepared by

a) Making MgCl₂And C₁-C₂Spray-or emulsion-solidified adducts of alcohols with TiCl₄Reaction of

b) At the C₁To C₂Reaction of the product of stage a) with a dialkyl phthalate of formula (I) under conditions such that transesterification between the alcohol and the dialkyl phthalate of formula (I) takes place to form an internal donor

Wherein R is^1’And R^2’Independently at least C₅Alkyl radical

c) Washing the product of stage b), or

d) Optionally mixing the product of step c) with additional TiCl₄And (4) reacting.

"phthalic acid" Ziegler-Natta procatalysts are produced, for example, as defined in patent applications WO 87/07620, WO 92/19653, WO 92/19658 and EP 0491566. The contents of these documents are incorporated herein by reference.

First MgCl is formed₂And C₁-C₂Of alcohols of the formula MgCl₂An adduct of nROH, wherein R is methyl or ethyl and n is 1 to 6. Ethanol is preferably used as the alcohol.

The adduct, which is melted and then spray-crystallized or emulsion-solidified, is used as a catalyst support.

In the next step, the spray-crystallized or emulsion-solidified MgCl of formula₂Adduct of nROH with TiCl₄Wherein R is methyl or ethyl, preferably ethyl, and n is 1 to 6, to form a titanized support, followed by the following steps

Adding to the titanized support

(i) A dialkyl phthalate of the formula (I) wherein R^1’And R^2’Independently at least C₅Alkyl radicals, e.g. at least C₈-an alkyl group,

or preferably

(ii) A dialkyl phthalate of the formula (I) wherein R^1’And R^2’Are identical and are at least C₅Alkyl radicals, e.g. at least C₈-an alkyl group,

or more preferably

(iii) A dialkyl phthalate of formula (I) selected from the group consisting of: propylhexyl phthalate (PrHP), dioctyl phthalate (DOP), diisodecyl phthalate (DIDP) and ditridecyl phthalate (DTDP), still more preferably the dialkyl phthalate of formula (I) is dioctyl phthalate (DOP), such as diisooctyl phthalate or di (ethylhexyl) phthalate, especially di (ethylhexyl) phthalate,

in order to form a first product which is,

subjecting the first product to suitable transesterification conditions, i.e. a temperature above 100 ℃, preferably between 100 and 150 ℃, more preferably between 130 and 150 ℃, such that the methanol or ethanol transesterifies with the ester groups of the dialkyl phthalate of formula (I) to form preferably at least 80 mole%, more preferably 90 mole%, most preferably 95 mole% of the dialkyl phthalate of formula (II)

Wherein R is¹And R²Is a methyl or ethyl group, preferably an ethyl group,

a dialkyl phthalate of the formula (II) as internal donor, and

recovering the transesterification product as the main catalyst component (i)).

In a preferred embodiment, MgCl is the formula₂An adduct of nROH (wherein R is methyl or ethyl and n is 1 to 6) is melted and thenThe melt is preferably injected from a gas into a cooled solvent or cooled gas, whereby the adduct crystallizes into a morphologically advantageous form, as described for example in WO 87/07620.

The crystalline adduct is preferably used as a catalyst support and reacted as a procatalyst useful in the present invention as described in WO 92/19658 and WO 92/19653.

The catalyst residue is removed by extraction to obtain an adduct of the titanized support and the internal donor in which the group originating from the ester alcohol has been changed.

If there is sufficient titanium on the support, it will act as the active element of the procatalyst.

Otherwise, the titanation is repeated after the above treatment to ensure a sufficient titanium concentration and thus activity.

Preferably, the "phthalic acid" Ziegler-Natta procatalyst used according to the invention contains at most 2.5% by weight titanium, preferably at most 2.2% by weight, more preferably at most 2.0% by weight. The donor content thereof is preferably between 4 and 12% by weight, more preferably between 6 and 10% by weight.

More preferably, the "phthalic acid" ziegler-natta procatalyst used according to the present invention is produced by: the use of ethanol as alcohol and dioctyl phthalate (DOP) as dialkyl phthalate of formula (I) yields diethyl phthalate (DEP) as internal donor compound.

Still more preferably, the "phthalic acid" ziegler-natta procatalyst used according to the present invention is the catalyst described in the examples section; in particular, dioctyl phthalate is used as dialkyl phthalate of the formula (I).

For the production of the heterophasic propylene copolymer (HECO) according to the present invention, the catalyst system used preferably comprises, in addition to the specific ziegler-natta procatalyst ("non-phthalic acid" or "phthalic acid"), an organometallic cocatalyst as component (ii).

Thus, the cocatalyst is preferably selected from the group consisting of: trialkylaluminums, such as Triethylaluminum (TEA), dialkylaluminum chlorides, and alkylaluminum sesquichlorides. Triethylaluminium (TEA) is particularly preferred.

Component (iii) of the catalyst system used is an external donor represented by formula (IIIa) or (IIIb). Formula (IIIa) is as defined

Si(OCH₃)₂R₂ ⁵ (IIIa)

Wherein R is⁵Represents a branched alkyl group having 3 to 12 carbon atoms, preferably a branched alkyl group having 3 to 6 carbon atoms, or a cyclic alkyl group having 4 to 12 carbon atoms, preferably a cyclic alkyl group having 5 to 8 carbon atoms.

It is particularly preferred that R⁵Selected from the group consisting of isopropyl, isobutyl, isopentyl, tert-butyl, tert-pentyl, neopentyl, cyclopentyl, cyclohexyl, methylcyclopentyl and cycloheptyl.

Formula (IIIb) is as defined

Si(OCH₂CH₃)₃(NR^xR^y) (IIIb)

Wherein R is^xAnd R^yWhich may be the same or different, represent a hydrocarbon group having 1 to 12 carbon atoms.

R^xAnd R^yIndependently selected from the group consisting of: a straight-chain aliphatic hydroxyl group having 1 to 12 carbon atoms, a branched-chain aliphatic hydroxyl group having 1 to 12 carbon atoms, and a cyclic aliphatic hydroxyl group having 1 to 12 carbon atoms. It is particularly preferred that R^xAnd R^yIndependently selected from the group consisting of: methyl, ethyl, n-propyl, n-butyl, octyl, decyl, isopropyl, isobutyl, isopentyl, tert-butyl, tert-pentyl, neopentyl, cyclopentyl, cyclohexyl, methylcyclopentyl and cycloheptyl.

More preferably, R^xAnd R^ySame, yet more preferably, R^xAnd R^yAre all ethyl groups.

More preferably, the external donor has formula (IIIa), such as dicyclopentyldimethoxysilane [ Si (OCH)₃)₂(cyclopentyl)₂]Diisopropyl dimethoxysilane [ Si (OCH)₃)₂(CH(CH₃)₂)₂]。

Most preferably, the external donor is dicyclopentyldimethoxysilane [ Si (OCH)₃)₂(cyclopentyl)₂](D-donor).

In a further embodiment, the Ziegler-Natta procatalyst may be modified by: polymerizing a vinyl compound in the presence of a catalyst system comprising a special ziegler-natta procatalyst (component (i)), an external donor (component (iii)) and optionally a cocatalyst (component (iii)), the vinyl compound having the formula:

CH₂＝CH-CHR³R⁴

wherein R is³And R⁴Together form a 5-or 6-membered saturated, unsaturated or aromatic ring, or independently represent an alkyl group comprising 1 to 4 carbon atoms, according to the invention, the modified catalyst is used for the preparation of the heterophasic propylene copolymer (HECO). The polymerized vinyl compound can act as an alpha-nucleating agent.

Preferred vinyl monomers for the preparation of the polymeric nucleating agents used according to the invention are in particular vinylcycloalkanes, in particular Vinylcyclohexane (VCH), vinylcyclopentanes and vinyl-2-methylcyclohexane, 3-methyl-1-butene, 3-ethyl-l-hexene, 3-methyl-1-pentene, 4-methyl-l-pentene or mixtures thereof.

It is particularly preferred that the polymeric nucleating agent is selected from the group of polyvinyl alkanes or polyvinyl cycloalkanes, in particular polyvinyl cyclohexane (polyVCH), polyvinyl cyclopentane, polyvinyl-2-methylcyclohexane, poly-3-methyl-1-butene, poly-3-ethyl-l-hexene, poly-4-methyl-1-pentene, polystyrene, poly-p-methylstyrene, polyvinyl norbornane (polyvinylnorbonane) or mixtures thereof. The most preferred compound is polyvinylcyclohexane (polyVCH).

With regard to the modification of the catalyst, reference is made to international applications WO 99/24478, WO 99/24479, in particular WO 00/68315, which are incorporated herein by reference with regard to the reaction conditions for the modification of the catalyst and the polymerization reaction.

Additive (AD)

As mentioned above, the composition according to the invention must comprise a Recycled Polymer Composition (RPC) and a heterophasic propylene copolymer (HECO), and possibly additional Additives (AD). However, the Recycled Polymer Composition (RPC) and the heterophasic propylene copolymer (HECO), respectively, may already contain additives themselves. Thus, when referring to "Additive (AD)" according to the present invention, the additive is meant to be added in addition to the additives already present in the Recycled Polymer Composition (RPC) and the heterophasic propylene copolymer (HECO), respectively.

Typical Additives (AD) are alpha-nucleating agents (in particular as defined under the section "heterophasic propylene copolymer (HECO)"), stabilizers such as uv stabilizers, hindered amine stabilizers (HALS), process stabilizers (such as phosphites), long-term stabilizers (such as thiosynergists and phenolic antioxidants), alkyl radical scavengers, lubricants, processing aids, pigments and blowing agents. These Additives are commercially available and are described, for example, in "plastics Additives Handbook", 2009, 6 th edition by Hans Zweifel (pages 1141 to 1190).

Furthermore, according to the invention, the term "additive" also comprises carrier materials, in particular polymeric carrier materials, in which the active additive can be dispersed. That is, according to the invention, "additive" also covers a masterbatch comprising a polymeric carrier material (such as polypropylene) and the reactive additive mentioned in the preceding paragraph.

In discussing the compositions of the invention, the amount of Additive (AD) is as indicated above.

Pipeline

In a further embodiment, the present invention relates to a pipe comprising at least 90 wt. -%, more preferably at least 95 wt. -%, based on the weight of the pipe, of the composition according to the present invention. In a particularly preferred embodiment, the pipe consists of a composition according to the invention.

The invention also relates to a pipe according to the invention, characterized in that the pipe has a pressure test performance measured according to ISO 1167 at a stress level of 2.5MPa and a temperature of 95 ℃ of more than 1000 hours.

The invention further provides a method for producing a pipe according to the invention, comprising the steps of:

a) optionally preparing a composition according to the invention

And

b) extruding the composition into the shape of a pipe.

The pipe according to the invention is generally produced according to methods known in the art. Thus, according to a preferred method, the composition of the invention is extruded through an annular die to the desired internal diameter and then the composition of the invention is cooled.

The extruder is preferably operated at a relatively low temperature, so excessive heat build-up should be avoided. Extruders having a high aspect ratio L/D of more than 15, preferably at least 20, in particular at least 25, are preferred. Modern extruders typically have an L/D ratio of about 30 to 35.

The polymer melt is extruded through an annular die, which may be arranged in an end-fed or side-fed configuration. The side feed die is often mounted with its axis parallel to the axis of the extruder, requiring a right angle turn at the connection to the extruder. An advantage of a side-feed die is that the mandrel can extend through the die, which makes it easy to access the mandrel, for example, by cooling water pipes.

After the plastic melt exits the die, it is calibrated to the correct diameter. In one method, the extrudate is directed to a metal tube (calibration sleeve). Vacuum pressure is applied to the outside of the extrudate to press the plastic against the tube walls.

According to another method, the extrudate exiting the die is directed into a tube having a perforated portion in the center. A slight vacuum is drawn through the perforations to hold the tubing against the walls of the sizing chamber.

After sizing, the pipe is cooled, typically in a water bath having a length of about 5 meters or more.

Use of

As mentioned above, the present invention also relates to the use of the heterophasic propylene copolymer (HECO) as defined in the present invention as a compatibilizer for Recycled Polymer Compositions (RPC) in pipes.

The invention therefore relates in particular to the use of a heterophasic propylene copolymer (HECO) as a compatibilizer for a Recycled Polymer Composition (RPC) in pipes,

wherein

(a) The heterophasic propylene copolymer (HECO) has

(a1) A Xylene Cold Soluble (XCS) fraction determined according ISO 16152 at 25 ℃ in the range of 9 to 18 wt. -%,

and

(a2) melt flow Rate MFR measured according to ISO 1133 in the range of 0.05 to 1.5g/10min₂(230℃/2.16kg)，

And

(b) the Recycled Polymer Composition (RPC) comprises at least 80 wt% recycled polypropylene, based on the weight of the Recycled Polymer Composition (RPC),

wherein the heterophasic propylene copolymer (HECO), the Recycled Polymer Composition (RPC) and optional Additives (AD) are further blended to form a composition as part of a pipe,

wherein further

(c) The weight ratio between the heterophasic propylene copolymer (HECO) and the Recycled Polymer Composition (RPC) [ (HECO)/(RPC) ] is in the range of 1.1 to 7.0, and

Preferably, the heterophasic propylene copolymer (HECO), the Recycled Polymer Composition (RPC) and the optional Additives (AD) are used in the form of a composition, in particular in the form of a composition as defined herein.

Thus, reference is made to the information provided above with respect to preferred embodiments of the amounts of the components in the composition according to the invention. In addition, with regard to preferred embodiments of the individual components of the composition, reference is made to the information provided above.

Hereinafter, the present invention is described by way of preferred embodiments.

Examples

Measuring method

The following definitions of terms and determination methods apply to the above general description of the invention as well as to the examples below, unless otherwise defined.

Melt flow Rate MFR₂(230 ℃/2.16kg) was determined according to ISO 1133 at 230 ℃ and under a load of 2.16 kg.

Quantification of microstructure by NMR spectroscopy

Quantitative Nuclear Magnetic Resonance (NMR) spectroscopy was used to quantify the comonomer content and comonomer sequence distribution of the polymer. Adopt a pair¹H and¹³c Bruker Advance III 400 NMR spectrometers operating at 400.15 and 100.62MHz respectively record quantitative measurements in solution¹³C{¹H } NMR spectrum. All spectral uses¹³C optimized 10mm extended temperature probe was recorded at 125 ℃, using nitrogen for all pneumatic devices. About 200mg of material was mixed with chromium (III) acetylacetonate (Cr (acac)₃) Dissolved in 3ml of 1, 2-tetrachloroethane-d₂(TCE-d₂) A 65mM solution of the relaxant in solvent was obtained (Singh, g., Kothari, a., Gupta, v., Polymer Testing 285 (2009), 475). To ensure homogeneity of the solution, after preparation of the initial sample in the heating block, the NMR tube was further heated in a rotary oven for at least 1 hour. After the magnet was inserted, the tube was rotated at 10 Hz. This setting is chosen primarily for high resolution and is quantitatively needed due to the quantification of accurate ethylene content. Using standard single pulse excitation without NOE, an optimized tip angle (tip angle), 1s cycle delay and a dual-stage WALTZ16 decoupling scheme (Zhou, z., Kuemmerle, r., Qiu, x., Redwine, d., conv, r., Taha, a., Baugh, d.winnford, b., j.mag.reson.187(2007) 225; Busico, v., Carbonniere, p., Cipullo, r., pellechia, r., Severn, j., talaro, g., macromol.rapid commu.2007, 28,1128) was used. A total of 6144(6k) transient signals were acquired per spectrum.

Quantification using proprietary computer programs¹³C{¹H NMR spectra were processed, integrated and relevant quantitative properties were determined from the integrations. Using the chemical shifts of the solvent, all chemical shifts are indirectly referenced to the central methylene group of the ethylene block (EEE) at 30.00 ppm. This method allows comparable results even if the structural unit is not presentFor reference. A characteristic signal corresponding to the incorporation of ethylene can be observed (Cheng, h.n., Macromolecules 17(1984), 1950).

For polypropylene homopolymer, all chemical shifts are internally referenced to methyl isotactic pentads (mmmm) at 21.85 ppm.

Characteristic signals corresponding to regio-defects (Resconi, L., Cavallo, L., Fait, A., Piemontesi, F., chem.Rev.2000,100, 1253; Wang, W-J., Zhu, S., Macromolecules 33(2000), 1157; Cheng, H.N., Macromolecules 17(1984),1950) or comonomers are observed.

The tacticity distribution was quantified by correcting any sites not related to the stereo sequence of interest by integration of the methyl region between 23.6-19.7ppm (Busico, V., Cipullo, R., prog.Polym.Sci.26(2001) 443; Busico, V., Cipullo, R., Monaco, G., Vacatello, M., Segre, A.L., Macromoleucles 30(1997) 6251).

Specifically, the effect of regio-defects and comonomer on the quantification of tacticity distribution is corrected by subtracting representative regio-defects and comonomer integrals from specific integral regions of the stereo sequence.

Isotacticity is determined at the pentad level and is reported as the percentage of isotactic pentad (mmmm) sequences over all pentad sequences:

[ mmmm ]% ═ 100 [ (% mmmm/sum of all pentads) ]

The presence of 2, 1-erythro defects is indicated by the presence of two methyl sites at 17.7 and 17.2ppm and confirmed by other characteristic sites.

No characteristic signals corresponding to other types of area defects were observed (Resconi, l., cavalo, l., Fait, a., Piemontesi, f., chem. rev.2000,100, 1253).

The amount of 2, 1-erythro regio defects was quantified using the average integral of the two characteristic methyl sites at 17.7 and 17.2 ppm.

P_21e＝(I_e6+I_e8)/2

The number of 1,2 primary insertions of propylene is quantified based on the methyl region and corrected for sites contained within the region that are not involved in the primary insertion and primary insertion sites not contained within the region.

P₁₂＝I_CH3+P_12e

The total amount of propylene was quantified as the sum of the primary insertion propylene and all other regio defects present.

P_{General assembly}＝P₁₂+P_21e

The mole percent of 2, 1-erythro regio defects was quantified for all propylene.

[21e]Mol% (% P) 100_21e/P_{General assembly})

For the copolymers, a characteristic signal corresponding to the incorporation of ethylene was observed (Cheng, h.n., Macromolecules 17(1984), 1950).

In the case of regio-defects (Resconi, L., Cavallo, L., Fait, A., Piemontesi, F., chem.Rev.2000,100, 1253; Wang, W-J., Zhu, S., Macromolecules 33(2000), 1157; Cheng, H.N., Macromolecules 17(1984),1950) also observed, it is necessary to correct the effect of these defects on the comonomer content.

The method of Wang et al (Wang, W-J., Zhu, S., Macromolecules 33(2000),1157) was used by¹³C{¹H integration of multiple signals over the entire spectral region in the spectrum quantifies the comonomer fraction. This method was chosen for its robustness and ability to account for the presence of regional defects when needed. The integration region is adjusted slightly to improve applicability over the entire range of comonomer contents encountered.

For systems where only isolated ethylene is observed in the PPEPP sequence, the Wang et al method was modified to reduce the effect of non-zero integration of sites known to be absent. This approach reduces overestimation of ethylene content in such systems and is achieved by reducing the number of sites used to determine absolute ethylene content to:

E＝0.5(Sββ+Sβγ+Sβδ+0.5(Sαβ+Sαγ))

by using this set of loci, the corresponding integral equation becomes:

E＝0.5(I_H+I_G+0.5(I_C+I_D))

the same notation as used in Wang et al (Wang, W-j., Zhu, s., Macromolecules 33(2000),1157) was used. The equation for absolute propylene content is not modified.

The mole percentage of comonomer incorporation was calculated from the mole fraction:

e [ mol% ] -100 fE

The weight percent comonomer incorporation was calculated from the mole fraction:

e [ wt% ] ═ 100 (fE × 28.06)/((fE × 28.06) + ((1-fE) × 42.08))

The sequence distribution of the comonomers at the triad level was determined using the analytical method of Kakugo et al (Kakugo, m., Naito, y., mizunma, k., Miyatake, t.macromolecules 15(1982) 1150). This method was chosen for its robustness and slight adjustments to the integration region to increase applicability to a wider range of comonomer contents.

Limonene quantification was performed by standard addition using solid phase microextraction (HS-SPME-GC-MS).

50mg of the ground sample was weighed into a 20mL headspace vial, and after the addition of different concentrations of limonene and a glass-coated magnetic stir bar, the vial was capped with a silicone/PTFE lined magnetic cap. A known concentration of diluted limonene standard was added to the sample using a microcapillary tube (10 pL). Limonene was added in amounts of 0, 2, 20 and 100ng corresponding to 0mg/kg, 0.1mg/kg, 1mg/kg and 5mg/kg, and additionally, standard amounts of 6.6mg/kg, 11mg/kg and 16.5mg/kg of limonene were used in combination with some of the samples tested in this application. For quantification, ion-93 collected in SIM mode was used. The volatile components were enriched by headspace solid phase microextraction using a 2cm stationary curved 50/30pm DVB/Carboxen/PDMS fiber for 20 minutes at 60 ℃. The desorption was carried out directly in the heated inlet of the GCMS system at 270 ℃.

GCMS parameters:

column: 30m HP 5MS 0.25X 0.25

Sample injector: no split, with 0.75mm SPME liner, 270 deg.C

Temperature program: -10 ℃ (1min)

Carrier gas: helium 5.0, 31cm/s linear velocity, constant flow

MS: a single quadrupole rod, a direct interface, the interface temperature of 280 DEG C

Collecting: SIM scanning mode

Scanning parameters are as follows: 20-300amu

SIM parameters: m/Z93, 100ms residence time

Total free fatty acid content

The fatty acids were quantified by standard addition using headspace solid phase microextraction (HS-SPME-GC-MS).

50mg of the ground sample was weighed into a 20mL headspace vial, and after the addition of different concentrations of limonene and a glass-coated magnetic stir bar, the vial was capped with a silicone/PTFE lined magnetic cap. Diluted free fatty acid mixture (acetic, propionic, butyric, valeric, caproic and caprylic) standards of known concentration were added to the samples at three different concentrations using 10 μ L microcapillaries. The addition of 0, 50, 100 and 500ng corresponded to 0mg/kg, 1mg/kg, 2mg/kg and 10mg/kg of each individual acid. All acids except propionic acid (ion 74 is used here) were quantified using ion 60 collected in SIM mode.

GCMS parameters:

column: 20m ZB Wax plus 0.25 × 0.25

Sample injector: split ratio (split)5:1, split gasket with glass liner, 250 deg.C

Temperature program: 40 deg.C (1min) @6 deg.C/min to 120 deg.C and @15 deg.C to 245 deg.C (5min)

Carrier gas: helium 5.0, 40cm/s linear velocity, constant flow

MS: a single quadrupole rod is directly connected with the interface, and the temperature of the interface is 220 DEG C

Collecting: SIM scanning mode

Scanning parameters are as follows: 46-250amu 6.6 scans/sec

SIM parameters: m/z 60, 74, 6.6 scans/sec

FTIR spectroscopy

Determination of the components and their amounts in the recycled polymer composition by FTIR spectroscopy:

resolution ratio: 2cm^-1

Thickness of compression molded sample layer: about 100 μm

Apodization: high strength

The method comprises the following steps: transmission through

Polypropylene: 1167cm^-1

Polystyrene: 1601.5cm^-1

Polyamide: 3300cm^-1

Talc: 3676cm^-1

Chalk: 1797cm^-1

The balance to 100% by weight being polyethylene

Notched impact Strength of simply Supported beams 80X 10X 4mm according to ISO 1791 eA injection moulding according to EN ISO 1873-2 at 23 ℃³And (5) testing by using a test bar.

Tensile modulus was determined according to ISO 527-2 (crosshead speed 50 mm/min; 23 ℃) using injection-molded specimens (dog-bone shape, 4mm thickness) as described in EN ISO 1873-2.

Density of the polymers was determined according to IS 01183-1: 2004 method A on compression-moulded test specimens prepared according to EN IS 01872-2 (2 months 2007) in g/cm³。

Xylene Cold Soluble (XCS) content according to ISO 16152; a first edition; 2005-07-01 was measured at 25 ℃.

The Intrinsic Viscosity (IV) was determined in accordance with DIN ISO 1628/1, 10 months 1999 (at 135 ℃ in decalin).

Heat Deflection Temperature (HDT) 80X 10X 4mm according to ISO 75A using injection moulding according to EN ISO 1873-2 at a load of 1.8MPa³And (5) testing by using a test bar.

The Oxidative Induction Time (OIT) is determined at 200 ℃ according to ISO11357-6 using TA instruments Q20. The instrument was calibrated with indium and tin according to ISO 11357-1. Each polymer sample (cylindrical, 5mm diameter, 0.5. + -. 0.05mm thickness) was placed in an open aluminium crucible under nitrogen for 20 ℃ min^-1At a rate of from 25 ℃ to 200 ℃ at a gas flow rate of 50mL min^-1After allowing to stand for 5min, the atmosphere was switched to oxygen at a flow rate of 50mL min^-1. The sample was kept at a constant temperature and recorded in relation to oxidationExothermic heat. The oxidation induction time is the time interval from the start of the oxygen flow to the start of the oxidation reaction.

Pipeline pressure testing

Pressure test performance was measured according to ISO 1167. In this test, the test specimen is exposed to a constant circumferential (hoop) stress of 2.5MPa with water in water at an elevated temperature of 95 ℃. The time to failure was recorded in hours. The tests were carried out on pipes produced on conventional pipe extrusion equipment, the pipes having a diameter of 110mm and a wall thickness of 4 mm.

FNCT (full notch creep test) was determined according to ISO 16770. The test specimens are compression molded plaques (10 mm in thickness). The samples were subjected to stress tests in aqueous solution at 80 ℃ and 4 MPa. Each sample was tested on 3 coupons. The average of three measurements was used to report time in hours.

The drop hammer impact test was carried out at-10 ℃.

To actually test the impact resistance, the pipes were subjected to external impact using the ladder method according to EN 1411. In this test, a series of pipes were conditioned at-10 ℃ and subjected to drop peening from different heights. Thus, H₅₀[＝mm]Indicating a 50% height of pipe failure.

Adjusting the temperature: -10 ℃; adjusting the period: 60 min; adjusting: in air; a striker: d 25; weight: 10 kg.

The ring stiffness test was carried out according to ISO 9969 at +23 ℃ on a pipe of diameter 110mm and wall thickness 4 mm.

Examples

Many blends were produced using DIPOLEN PP, a polypropylene-rich recycled plastic material (material from Mtm Plastics GmbH, according to the 2014 2 month specification) as a recycled polymer composition (RCP). 15 to 40 wt% of a heterophasic propylene copolymer (HECO) was added to each blend as a compatibilizer.

The compositions were prepared by melt blending on a co-rotating twin screw extruder. The polymer melt mixture was discharged and pelletized.

Hereinafter, the components used will be explained in more detail:

recycled polymer composition (RCP): DIPELEN PP

Table 1: composition of Dipolen PP

Table 2: limonene content in DIPOLEN PP

Table 3: total fatty acid content in Dipolen PP

Heterophasic propylene copolymer (HECO)

Preparation of the catalyst

First, 0.1 mol of MgCl₂X 3EtOH was suspended in 250ml decane under inert conditions in an atmospheric reactor. The solution was cooled to a temperature of-15 ℃ and 300ml of cold TiCl were added while keeping the temperature at said level₄. The slurry temperature was then slowly increased to 20 ℃. At this temperature, 0.02 mol of di (ethylhexyl) phthalate (DOP) was added to the slurry. After the addition of the phthalate, the temperature was increased to 135 ℃ over 90 minutes and the slurry was allowed to stand for 60 minutes. Then, 300ml of TiCl were added₄And the temperature was maintained at 135 ℃ for 120 minutes. Thereafter, the catalyst was filtered from the liquid and washed 6 times with 300ml of 80 ℃ heptane. Then, the solid catalyst component was filtered and dried. The catalysts and the preparation concepts thereof are generally described, for example, in patent publications EP 491566, EP 591224 and EP 586390.

For the preparation of HECO, as shown below, Triethylaluminium (TEAL), dicyclopentyldimethoxysilane (D-donor), the catalyst produced as described above and Vinylcyclohexane (VCH) are added to an oil, such as a mineral oil, for example Technol 68 (kinematic viscosity at 40 ℃ from 62 to 74cSt), in amounts such that TEAL/Ti is 125mol/mol, TEAL/D donor is 5mol/mol, VCH/solid catalyst in a weight ratio of 1: 1. the mixture was heated to 60 to 65 ℃ and allowed to react until the content of unreacted vinylcyclohexane in the reaction mixture was 150 ppm. The catalyst concentration in the final oil-catalyst slurry is 10 to 20 wt%.

Table 4: polymerization conditions for heterophasic propylene copolymers (HECO)

C2 ethylene

IV intrinsic viscosity

XCS xylene cold soluble fraction

H₂/C₃Specific hydrogen/propylene ratio

C₂/C₃Specific ethylene/propylene ratio

Loop Loop reactor

1/2 GPR 1/2 gas phase reactor

The heterophasic propylene copolymer (HECO) was melt mixed with 0.1 wt% Irgafos 168, 0.15 wt% Irganox 1010 and 0.2 wt% Irganox PS 802.

Table 5: properties of the composition

The production mode of the pipeline is as follows:

the compositions in table 5 were extruded into solid wall tubes in the following manner:

outer diameter: 110mm

Wall thickness: 4mm

The extruder was a Kraus Maffei 36D single screw extruder with a screw diameter of 45mm

Temperature distribution: a barrel area: 220/220/215/210/210 deg.C;

120 kg/h; production line speed is 1.56m/min

Table 6: performance of the pipe

		IE1	IE2	IE3
					Testing the pipeline pressure at 95 ℃; 2.5MPa	[h]	1960	1900	900
Rigidity of ring	[kN/m²]	8.9	7.8	7.5
					Drop hammer ladder	[mm]	2610	2480	2180

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Composition for pipes containing recycled material

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