阅读说明：本技术 一种聚丙烯组合物及其制备方法 (Polypropylene composition and preparation method thereof ) 是由 雷亮 叶南飚 陈平绪 俞飞 陈嘉杰 胡佳旭 马金成 吴国峰 杨波 罗忠富 于 2021-08-17 设计创作，主要内容包括：本发明公开了一种聚丙烯组合物及其制备方法,属于高分子材料技术领域。本发明所述聚丙烯组合物通过在聚丙烯树脂组分中添加特定含量的针状硅酸钙代替传统透光率较低的滑石粉作为填充剂,可有效提高产品的透光率；同时在聚丙烯组分中添加特定增韧剂与其他组分实现协同作用,所得产品兼具优异的力学性能。本发明还公开了所述聚丙烯组合物的制备方法,该制备方法操作步骤简单,可实现工业化大规模生产。本发明还公开了所述聚丙烯组合物在制备汽车塑料零部件中的应用。(The invention discloses a polypropylene composition and a preparation method thereof, belonging to the technical field of high polymer materials. According to the polypropylene composition, the needle-shaped calcium silicate with specific content is added into the polypropylene resin component to replace the traditional talcum powder with low light transmittance as a filler, so that the light transmittance of the product can be effectively improved; meanwhile, a specific toughening agent is added into the polypropylene component to realize the synergistic effect with other components, and the obtained product has excellent mechanical properties. The invention also discloses a preparation method of the polypropylene composition, which has simple operation steps and can realize industrial large-scale production. The invention also discloses application of the polypropylene composition in preparation of automobile plastic parts.)

1. The polypropylene composition is characterized by comprising the following components in parts by weight: 70-99.8 parts of polypropylene resin, 0-30 parts of toughening agent and 5-20 parts of needle-shaped calcium silicate.

2. The polypropylene composition according to claim 1, wherein the polypropylene composition comprises 8 to 15 parts of acicular calcium silicate.

3. The polypropylene composition according to claim 1, wherein the acicular calcium silicate has an average diameter of 0.5 to 1.5 μm and an average length of 28 to 32 μm.

4. The polypropylene composition according to claim 3, wherein the acicular calcium silicate particles with a diameter distribution of 0.5 to 1.5 μm account for 70 to 80% by mass of the overall acicular calcium silicate; the mass content of the needle-shaped calcium silicate particles with the length distribution of 28-32 mu m accounts for 70-80% of the mass content of the whole needle-shaped calcium silicate.

5. The polypropylene composition according to claim 1, wherein the polypropylene resin comprises at least one of a co-polypropylene resin and a homo-polypropylene resin, and the polypropylene resin has a melt mass flow rate of 28 to 32g/10min, as measured at 230 ℃ using a 2.16kg weight according to astm d 1238.

6. The polypropylene composition of claim 1, wherein the toughening agent comprises at least one of an ethylene-butene copolymer, an ethylene-octene copolymer, and a styrenic copolymer elastomer.

7. The polypropylene composition of claim 1, wherein the polypropylene composition comprises 2 to 25 parts of a toughening agent.

8. The polypropylene composition according to claim 1, wherein the components further comprise 0-2 parts of auxiliaries, and the auxiliaries comprise an antioxidant and a light stabilizer; preferably, the antioxidant comprises at least one of hindered phenol antioxidants and phosphite antioxidants, and the light stabilizer comprises hindered amine light stabilizers.

9. A process for the preparation of a polypropylene composition according to any one of claims 1 to 8, comprising the steps of:

and uniformly mixing the polypropylene resin, the toughening agent, the needle-shaped calcium silicate and the auxiliary agent, and then carrying out melt mixing and extrusion granulation to obtain the polypropylene composition.

10. Use of the polypropylene composition according to any one of claims 1 to 8 for the production of automotive plastic parts.

Technical Field

The invention relates to the technical field of high polymer materials, and particularly relates to a polypropylene composition and a preparation method thereof.

Background

Polypropylene (PP) has the advantages of low density, easy processing, excellent mechanical properties, etc., and has been widely used in various fields such as automobile industry, home appliances, and machinery, among which the automobile field is the most common. Nowadays, the automobile model is increasingly cool, and particularly for electric automobiles, the design sense of interior and exterior is stronger. On this basis, can design more attractive outward appearance effect to these products, like design intelligent touch-control regulation control system in the car, and then make the automobile body present effect such as printing opacity and luminous, and the realization of these effects needs to adopt high light transmittance material preparation automobile body spare part.

At present, light-transmitting materials on automobiles are mainly PC and PMMA, but PP is less in application, mainly because the PP material basically takes talcum powder as a filler to achieve ideal mechanical properties, but the light transmittance is low, so that the application of the PP material in the preparation of the light-transmitting materials is limited. Many studies have been made to improve the light transmission properties of polypropylene materials. CN201911308750.4 discloses a light-permeable polypropylene composition with good wear resistance and a preparation method thereof, and the technical scheme adopts glass beads to replace talc powder which is commonly added in the traditional polypropylene material as a filling material of the product, thereby improving the light transmittance of the polypropylene material. However, the glass beads are easily broken, which results in the reduction of the mechanical properties and light transmittance of the material. Therefore, there is still a need in the art to develop a polypropylene material with simple preparation method and high light transmittance for plastic parts of automobiles.

Disclosure of Invention

Based on the defects in the prior art, the invention aims to provide the polypropylene composition, and the light transmittance of the polypropylene material can be remarkably improved by adding needle-shaped calcium silicate with specific content into the components to replace the traditional talcum powder as a filler; meanwhile, the product contains a specific toughening agent component, so that the stability and the higher flexural modulus of the whole material can be guaranteed.

In order to achieve the purpose, the invention adopts the technical scheme that:

a polypropylene composition comprises the following components in parts by weight: 70-99.8 parts of polypropylene resin, 0-30 parts of toughening agent and 5-20 parts of needle-shaped calcium silicate.

The inventor unexpectedly finds that when calcium silicate with a needle structure with a proper content is added into a polypropylene material as a filling component, the light transmittance is better than that of the traditional talcum powder with a sheet structure and a stronger light reflection effect; meanwhile, the inventor also researches and screens the addition amount of the needle-shaped calcium silicate: the needle-shaped calcium silicate is a filler in the product, so that the mechanical property of the polypropylene resin is greatly influenced, if the addition amount of the needle-shaped calcium silicate is too low, the filler of the product is insufficient, and the flexural modulus of the product is low; however, if the amount is too high, the light transmittance is significantly reduced.

According to the polypropylene composition, the needle-shaped calcium silicate with specific content is added into the polypropylene resin component to replace the traditional talcum powder with low light transmittance as a filler, so that the light transmittance of the product can be effectively improved; meanwhile, the product can keep good flexural modulus and excellent comprehensive performance under the optimal proportion of the polypropylene component.

Preferably, the polypropylene composition comprises 8-15 parts of needle calcium silicate;

more preferably, the components of the polypropylene composition comprise 10 parts of acicular calcium silicate.

Under the action of preferably adding needle-shaped calcium silicate, the obtained polypropylene composition has high light transmittance, does not cause reduction of flexural modulus of products, and is kept above 2000MPa on average. Preferably, the needle-like calcium silicate has an average diameter of 0.5 to 1.5 μm and an average length of 28 to 32 μm.

More preferably, the acicular calcium silicate particles with the diameter distribution of 0.5-1.5 μm account for 70-80% of the mass content of the whole acicular calcium silicate; the mass content of the needle-shaped calcium silicate particles with the length distribution of 28-32 mu m accounts for 70-80% of the mass content of the whole needle-shaped calcium silicate.

The inventor of the application discovers that the length-diameter ratio of the needle-shaped calcium silicate also has influence on the light transmittance and the mechanical property of the prepared product after experimental screening; if the length-diameter ratio of the needle-shaped calcium silicate is too low, the coverage area of the filler in the material is increased, and the light transmittance of the product is reduced; if the aspect ratio is too high, the light transmittance of the product is high, but the stability of the product is affected, and the needle-like calcium silicate is broken at the time of subsequent extrusion, thereby deteriorating the flexural modulus of the product.

More preferably, the needle-like calcium silicate has an average diameter of 1 μm and an average length of 30 μm.

Preferably, the polypropylene resin is at least one of a co-polypropylene resin and a homo-polypropylene resin, the polypropylene resin has a melt Mass Flow Rate (MFR) of 28 to 32g/10min, the melt mass flow rate of the polypropylene resin is measured at a temperature of 230 ℃ using a 2.16kg weight according to astm d 1238.

Preferably, the toughening agent comprises ethylene-butene copolymer, ethylene-octene copolymer, and styrenic copolymer elastomers;

more preferably, the density of the toughening agent is 0.855-0.865 g/cm³The melt mass flow rate of the toughening agent is 0.8-1.2 g/10min, and the melt mass flow rate of the toughening agent is measured at a temperature of 190 ℃ using a weight of 2.16kg according to ASTM D1238.

More preferably, the polypropylene composition comprises 2-25 parts of toughening agent.

The addition amount of the toughening agent is not more and better, if the toughening agent is added too much, the light transmittance of the material is reduced, the toughness is not obviously improved, and the flexural modulus is reduced.

Preferably, the polypropylene composition further comprises 0-2 parts of an auxiliary agent, wherein the auxiliary agent comprises an antioxidant and a light stabilizer.

More preferably, the antioxidant comprises at least one of hindered phenol antioxidants and phosphite antioxidants;

more preferably, the antioxidant comprises at least one of antioxidant 1010, antioxidant 1076, antioxidant 3114, antioxidant 168 and antioxidant PEP-36.

By adding the antioxidant with proper content, the stability of the polypropylene resin in the preparation and storage processes of the product can be improved, and the side reaction of the product is avoided.

More preferably, the light stabilizer comprises a hindered amine light stabilizer;

more preferably, the light stabilizer comprises at least one of UV-3808PP5, LA-402XP, LA-402 AF.

Another object of the present invention is to provide a method for preparing the polypropylene composition, comprising the steps of:

and uniformly mixing the polypropylene resin, the toughening agent, the needle-shaped calcium silicate and the auxiliary agent, and then carrying out melt mixing and extrusion granulation to obtain the polypropylene composition.

The polypropylene composition disclosed by the invention is simple in preparation steps and can realize industrial large-scale production.

Preferably, the melting and mixing process is carried out in a double-screw extruder, the temperature during melting and mixing is 170-220 ℃, and the screw rotating speed in the double-screw extruder is 350-450 r/min.

It is a further object of the present invention to provide the use of said polypropylene composition for the preparation of plastic parts for automobiles.

The polypropylene composition disclosed by the invention is high in light transmittance and bending modulus, and can be effectively applied to the production of automobile plastic parts with higher requirements on light transmittance and impact performance.

The polypropylene composition has the beneficial effects that the needle-shaped calcium silicate with specific content is added into the polypropylene resin component to replace the traditional talcum powder with lower light transmittance as a filler, so that the light transmittance of the polypropylene composition can be effectively improved; meanwhile, under the preferable proportion of the polypropylene component, the flexural modulus of the product is improved compared with that of a polypropylene product prepared by talcum powder, and the comprehensive performance is excellent. The invention also provides a preparation method of the polypropylene composition, which has simple operation steps and can realize industrial large-scale production. The invention also provides application of the polypropylene composition in preparing automobile plastic parts.

Detailed Description

In order to better illustrate the objects, technical solutions and advantages of the present invention, the present invention will be further described with reference to specific examples and comparative examples, which are intended to be understood in detail, but not intended to limit the invention. All other embodiments obtained by a person skilled in the art without making any inventive step are within the scope of protection of the present invention. The experimental reagents and instruments involved in the practice of the present invention are, unless otherwise specified, common reagents and instruments.

In the examples, the melt mass flow rates of the polypropylene resin and toughener were measured according to astm d1238 using a 2.16kg weight and temperature of 230 ℃/190 ℃ respectively.

Example 1

In one embodiment of the polypropylene composition and the preparation method thereof according to the present invention, the components of the polypropylene composition are shown in table 1.

The preparation method of the polypropylene composition comprises the following steps:

uniformly mixing polypropylene resin, a toughening agent, needle-shaped calcium silicate and an auxiliary agent, adding the mixture into a double-screw extruder, and carrying out melt mixing and extrusion granulation to obtain the polypropylene composition; the temperature during the melting and mixing is 210 ℃, and the screw rotating speed in the double-screw extruder is 400 r/min.

The polypropylene resin is a copolymer polypropylene resin, a PP EP548R model product produced by Zhonghai Shell company, and the melt mass flow rate of the polypropylene resin is 30g/10 min;

the toughening agent is ethylene-butylene copolymer, POE ENGAGE 7467 type product produced by Dow chemical company, and the density of the toughening agent is 0.86g/cm³And the melt mass flow rate of the toughening agent is 1g/10 min.

The needle-shaped calcium silicate is a NYGLOS 4W product produced by NYCO company in America; screening the product; the average diameter of the needle-shaped calcium silicate is 1 mu m, and the average length of the needle-shaped calcium silicate is 30 mu m; the needle-shaped calcium silicate particles with the diameter distribution of 0.5-1.5 mu m account for 75% of the mass content of the whole needle-shaped calcium silicate, and the needle-shaped calcium silicate particles with the diameter distribution of more than 1.5 mu m account for 10% of the mass content of the whole needle-shaped calcium silicate; the needle-shaped calcium silicate particles with the diameter distribution of less than 0.5 mu m account for 15 percent of the mass content of the whole needle-shaped calcium silicate; the needle-shaped calcium silicate particles with the length distribution of 28-32 mu m account for 70% of the mass content of the whole needle-shaped calcium silicate; the needle-shaped calcium silicate particles with the length distribution of more than 32 mu m account for 15 percent of the mass content of the whole needle-shaped calcium silicate; the acicular calcium silicate particles with the length distribution of less than 28 mu m account for 15 percent of the mass content of the whole acicular calcium silicate.

The auxiliary agent comprises an antioxidant and a light stabilizer;

the antioxidant comprises hindered phenol antioxidant 1010 (tetra [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid ] pentaerythritol ester) and phosphite antioxidant 168 (tri [2, 4-di-tert-butylphenyl ] phosphite), which are all products produced by Pasteur Germany;

the light stabilizer is hindered amine light stabilizer 3808PP5, a product of UV-3808PP5 manufactured by Soervai, USA.

Examples 2 to 10, 14 to 15

The polypropylene composition of the present invention and the preparation method thereof have the components shown in Table 1. The preparation of the product described in each example was carried out in the same manner as in example 1.

Wherein the toughening agent in example 5 is ethylene-octene copolymer, POE ENAGEG 8842 product manufactured by Dow chemical company, and the density is 0.857g/cm³The melt mass flow rate of the toughening agent is 1g/10 min;

the polypropylene resin is homopolymerized polypropylene, and H9018 products are produced by Lanzhou petrochemical company; the melt mass flow rate of the polypropylene resin is 60g/10 min.

Example 11

The present embodiment differs from embodiment 3 only in that: the needle-shaped calcium silicate is a NYGLOS 4W product produced by NYCO company in America; screening the product; the needle-like calcium silicate had an average diameter of 1 μm and an average length of 10 μm.

Example 12

The present embodiment differs from embodiment 3 only in that: the toughening agent in the embodiment is an ethylene propylene elastomer; vistamax 3000 type product produced by exxonfu and having density of 0.873g/cm³And the melt mass flow rate of the toughening agent is 8.0g/10 min.

Example 13

The present embodiment differs from embodiment 3 only in that: the needle-shaped calcium silicate is a NYGLOS 8 product produced by NYCO company in America; screening the product; the needle-like calcium silicate had an average diameter of 2 μm and an average length of 35 μm.

Example 16

The present embodiment differs from embodiment 3 only in that: the needle-shaped calcium silicate is an ASPECT 3000 product produced by NYCO company in America; screening the product; the mass content of the needle-shaped calcium silicate particles with the diameter distribution of 0.5-1.5 mu m accounts for about 50% of the mass content of the whole needle-shaped calcium silicate, and the mass content of the needle-shaped calcium silicate particles with the diameter distribution of more than 1.5 mu m accounts for about 20% of the mass content of the whole needle-shaped calcium silicate; the acicular calcium silicate particles with the diameter distribution of less than 0.5 mu m account for about 30 percent of the mass content of the whole acicular calcium silicate; the needle-shaped calcium silicate particles with the length distribution of 28-32 mu m account for about 60% of the mass content of the whole needle-shaped calcium silicate; the acicular calcium silicate particles with the length distribution of more than 32 μm account for about 20% of the mass content of the overall acicular calcium silicate; the acicular calcium silicate particles having a length distribution of less than 28 μm comprise about 20% by mass of the overall acicular calcium silicate.

Comparative examples 1 to 4

The composition of the polypropylene of this comparative example is shown in Table 2. The preparation of the product according to each comparison is carried out as in example 1.

TABLE 1

TABLE 2

Effect example 1

The products obtained in examples 1 to 16 and comparative examples 1 to 4 were subjected to a light transmittance test and a flexural modulus test:

(1) and (3) testing light transmittance: each polypropylene composition was injection molded into 100 x 2.5mm square plaques, which were tested for light transmittance by a light transmittance tester according to GB2410-1980 transparent plastic light transmittance and haze test methods;

(2) flexural modulus test: the bending modulus and the bending rate of the material are tested by adopting ISO178-2010 (determination of plastic bending property) 2 mm/min;

the test results are shown in table 3.

TABLE 3

As shown by tests, when the polypropylene composition contains the needle-shaped calcium silicate with a specific content instead of the traditional talcum powder as a filler, the light transmittance of a final product is improved, and the flexural modulus is also improved, wherein the flexural modulus of the product obtained in example 3 is up to 2200MPa, and the light transmittance is more than 50 percent; if the content of the needle-shaped calcium silicate is too high, the light transmittance of the product is significantly reduced as described in comparative example 2; the test results of the products of examples 7 to 10, 14 and 4 show that the amount of the toughening agent added can balance the rigidity and toughness of the material to a certain extent and ensure a certain flexural modulus, but if the amount of the toughening agent added is too much, the flexural modulus of the material is reduced, and the light transmittance is also reduced; as can be seen from comparison of the products of examples 11 to 13 and 16 and comparative example 3, the selection of the types of the raw materials of the product, especially the types of the toughening agent and the acicular calcium silicate, also affects the light transmittance and flexural modulus of the product.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the protection scope of the present invention, and although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.