阅读说明：本技术 一种低收缩率、高韧性聚丙烯复合材料及其制备方法 (Low-shrinkage high-toughness polypropylene composite material and preparation method thereof ) 是由 杨桂生 宋伟华 姚晨光 邵灵芝 王�华 计娉婷 朱敏 于 2020-05-25 设计创作，主要内容包括：本发明公开了一种低收缩率、高韧性聚丙烯复合材料及其制备方法,复合材料由以下组分按重量份组成：聚丙烯：42～66份,聚乳酸：10～20份,增韧剂：5～10份,界面相容剂：4～8份,滑石粉：15～25份,耐热助剂：0.2～0.4份；所述界面相容剂为乙烯-丙烯酸乙酯-甲基丙烯酸缩水甘油酯三嵌段共聚物。本发明通过添加结晶速率低的聚乳酸,可以在一定程度上延缓聚丙烯结晶,降低聚丙烯的收缩率；通过添加增韧剂SEBS、界面相容剂E-MA-GMA,形成的SEBS物理交联网络与E-MA-GMA/聚丙烯/聚乳酸物理交联网络相互缠结,形成稳定的互穿网络结构,阻碍了材料的收缩,使材料的韧性和尺寸稳定性都得到显著提高。(The invention discloses a low-shrinkage high-toughness polypropylene composite material and a preparation method thereof, wherein the composite material comprises the following components in parts by weight: polypropylene: 42-66 parts of polylactic acid: 10-20 parts of a toughening agent: 5-10 parts of an interfacial compatilizer: 4-8 parts, talcum powder: 15-25 parts of a heat-resistant auxiliary agent: 0.2-0.4 part; the interfacial compatilizer is an ethylene-ethyl acrylate-glycidyl methacrylate triblock copolymer. According to the invention, by adding polylactic acid with low crystallization rate, the crystallization of polypropylene can be delayed to a certain extent, and the shrinkage rate of polypropylene is reduced; by adding the toughening agent SEBS and the interface compatilizer E-MA-GMA, the formed SEBS physical crosslinking network and the E-MA-GMA/polypropylene/polylactic acid physical crosslinking network are intertwined to form a stable interpenetrating network structure, so that the shrinkage of the material is hindered, and the toughness and the dimensional stability of the material are obviously improved.)

1. A low-shrinkage high-toughness polypropylene composite material is characterized in that: the composition comprises the following components in parts by weight:

polypropylene: 42 to 66 parts of a water-soluble polymer,

polylactic acid: 10-20 parts of (A) a water-soluble polymer,

a toughening agent: 5 to 10 parts by weight of a surfactant,

interface compatilizer: 4 to 8 parts of (A) a water-soluble polymer,

talc powder: 15 to 25 parts of (a) a water-soluble polymer,

heat-resistant auxiliary agent: 0.2-0.4 part;

the interfacial compatilizer is an ethylene-ethyl acrylate-glycidyl methacrylate triblock copolymer.

2. The low shrinkage, high toughness polypropylene composite of claim 1, wherein: the polypropylene is at least one of homo-polypropylene and co-polypropylene, and has a melt index of 10-100g/10min at 230 ℃ under the test condition of 2.16 kg.

3. The low shrinkage, high toughness polypropylene composite of claim 1, wherein: the weight average molecular weight of the polylactic acid is 1.0 multiplied by 10⁵～3.0×10⁵。

4. The low shrinkage, high toughness polypropylene composite of claim 1, wherein: the toughening agent is hydrogenated styrene-butadiene block copolymer.

5. The low shrinkage, high toughness polypropylene composite of claim 1, wherein: the particle size range of the talcum powder is 2-15 microns.

6. The low shrinkage, high toughness polypropylene composite of claim 1, wherein: the heat-resisting auxiliary agent is at least one of antioxidant 1010, antioxidant 168 and antioxidant 1076.

7. The method of preparing a low shrinkage, high toughness polypropylene composite as claimed in any one of claims 1 to 6, wherein: the method comprises the following steps:

(1) weighing polypropylene, polylactic acid, a toughening agent, an interfacial compatilizer, talcum powder and a heat-resistant auxiliary agent according to a ratio, and uniformly mixing to obtain a mixture;

(2) and adding the mixture into a double-screw extruder for extrusion, and cooling, drying and granulating the extruded material to obtain a final product, namely the low-shrinkage high-toughness polypropylene composite material.

8. The method of claim 7, wherein: in the step (2), the length-diameter ratio of the double-screw extruder is 48:1, and the temperature of each section of the double-screw extruder is 190-240 ℃.

Technical Field

The invention belongs to the technical field of modification and processing of high polymer materials, and particularly relates to a low-shrinkage high-toughness polypropylene composite material and a preparation method thereof.

Background

Polypropylene (PP) is one of general plastics, has the characteristics of high heat resistance, balanced strength, low density, good processability and the like, is low in price, and is widely applied to the fields of automobiles, household appliances and the like. However, polypropylene has high crystallinity, high shrinkage, and poor dimensional stability, which limits its use. The usual improvement is to reduce the shrinkage by adding mineral fillers and glass fibers to the raw materials, but these improvements all increase the density of the material significantly and reduce the impact toughness of the material. In recent years, the household electrical appliance and automobile industries are limited by cost and environmental protection, and the demand for polypropylene composite materials to replace ABS is increasingly strong. Therefore, the research on the preparation of polypropylene composite materials with low shrinkage and high toughness becomes one of the important directions of modified polypropylene.

Polylactic acid (PLA) is a polymer obtained by polymerizing lactic acid as a main raw material, is a green high polymer material, has good mechanical properties, biodegradability, chemical inertness and processability, is one of the most promising biodegradable high polymer materials, and has great potential application value in the fields of household appliances, automobiles and the like. The polylactic acid has low crystallization rate, can delay the crystallization of polypropylene to a certain extent, reduces the shrinkage rate of the polypropylene, and has great application prospect in the aspect of polypropylene modification.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a low-shrinkage high-toughness polypropylene composite material.

The purpose of the invention is realized by the following technical scheme:

a low-shrinkage high-toughness polypropylene composite material comprises the following components in parts by weight:

polypropylene: 42 to 66 parts of a water-soluble polymer,

polylactic acid: 10-20 parts of (A) a water-soluble polymer,

a toughening agent: 5 to 10 parts by weight of a surfactant,

interface compatilizer: 4 to 8 parts of (A) a water-soluble polymer,

talc powder: 15 to 25 parts of (a) a water-soluble polymer,

heat-resistant auxiliary agent: 0.2-0.4 part;

the interfacial compatilizer is ethylene-ethyl acrylate-glycidyl methacrylate triblock copolymer (E-MA-GMA).

In a further scheme, the polypropylene is at least one of homo-polypropylene and co-polypropylene, and the melt index of the polypropylene is 10-100g/10min under the test conditions of 230 ℃ and 2.16 kg.

In a further aspect, the weight average molecular weight of the polylactic acid is 1.0 × 10⁵～3.0×10⁵。

In a further embodiment, the toughening agent is hydrogenated styrene-butadiene block copolymer (SEBS).

In a further scheme, the particle size range of the talcum powder is 2-15 micrometers.

In a further scheme, the heat-resisting auxiliary agent is at least one of an antioxidant 1010, an antioxidant 168 and an antioxidant 1076.

The invention also aims to provide a preparation method of the low-shrinkage high-toughness polypropylene composite material, which comprises the following steps:

(1) weighing polypropylene, polylactic acid, a toughening agent, an interfacial compatilizer, talcum powder and a heat-resistant auxiliary agent according to a ratio, and uniformly mixing to obtain a mixture;

(2) and adding the mixture into a double-screw extruder for extrusion, and cooling, drying and granulating the extruded material to obtain a final product, namely the low-shrinkage high-toughness polypropylene composite material.

In the step (2), the length-diameter ratio of the double-screw extruder is 48:1, and the temperature of each section of the double-screw extruder is 190 ℃ to 240 DEG C

Compared with the prior art, the invention has the beneficial effects that:

(1) the polylactic acid with low crystallization rate is added in the formula of the invention, so that the crystallization of polypropylene can be delayed to a certain extent, and the shrinkage rate of the polypropylene is reduced.

(2) The invention adopts SEBS to toughen, when the SEBS is added into a composite material system, the polystyrene chain segment is a dispersed phase, the butylene chain segment is a continuous phase, and the chain segments are intertwined to form a physically crosslinked network; the added interface compatilizer is E-MA-GMA, the ethylene chain segment in the molecule has good compatibility with polypropylene, the epoxy group in the molecule has good compatibility with the terminal hydroxyl and the terminal carboxyl of polylactic acid, and the three also form a physically cross-linked network. The SEBS physical crosslinking network and the E-MA-GMA/polypropylene/polylactic acid physical crosslinking network are intertwined with each other to form a stable interpenetrating network structure, so that the shrinkage of the material is hindered, and the toughness and the dimensional stability of the material are obviously improved.

(3) The composite material prepared by the invention has low shrinkage, high toughness and high practical applicability.

Detailed Description

The present invention will be further described with reference to the following examples. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The types and suppliers of reagents used in the following examples and comparative examples are merely illustrative of the sources and components of reagents used in the experiments of the present invention and are fully disclosed, and do not indicate that the present invention cannot be practiced using other reagents of the same type or other suppliers.

The comprehensive performance of the material is judged by numerical values of tensile strength, cantilever beam notch impact strength and shrinkage rate. The pellets obtained in each of examples and comparative examples were injection-molded into standard test specimens and then subjected to a performance test. Tensile strength was performed according to ISO 527 with a test speed of 50mm/min, bars were dumbbell shaped, bar size was 170mm by 10mm by 4 mm; the notched impact strength of the cantilever beam is performed according to ISO 180, the notched impact strength of the cantilever beam at normal temperature (23 ℃) is tested, the sample strip is rectangular (V-shaped molding notch), and the size of the sample strip is 80mm x 10mm x 4 mm; shrinkage was performed according to ISO 294-4.

Example 1

42 parts of polypropylene (trade name S2040, Shanghai Seiki petrochemical industry, Inc.), 20 parts of polylactic acid (trade name 3052D, Nature Works, USA), 10 parts of SEBS (trade name 6150, Takeqi, Inc.), 8 parts of E-MA-GMA (trade name AX8900, Acoma group), 20 parts of talcum powder (trade name HTP1, Liaoning Aihai Talc, Inc.), 0.4 parts of heat-resistant auxiliary agent (0.2 part of antioxidant 1010 and 0.2 part of antioxidant 168, Bassfold, Inc.) are weighed and put into a high-speed mixer to be mixed to obtain a mixture. And adding the mixture into a double-screw extruder for extrusion, cooling the extruded strips to room temperature through a circulating water tank, drying the extruded strips by a blower, and then granulating the dried extruded strips in a granulator to obtain the low-shrinkage high-toughness polypropylene composite material.

The length-diameter ratio of the double-screw extruder is 48:1, and the temperatures of all sections of a charging barrel of the double-screw extruder are respectively set as follows: 200 ℃ in the first zone, 210 ℃ in the second zone, 215 ℃ in the third zone, 220 ℃ in the fourth zone, 225 ℃ in the fifth zone, 230 ℃ in the sixth zone and 230 ℃ in the head. The product obtained in example 1 was tested for its properties according to the corresponding standards, the results of which are shown in table 1.

Example 2

54 parts of polypropylene (trade name S2040, Shanghai Seisaku petrochemical industry, Ltd.), 15 parts of polylactic acid (trade name: REVODE201 Zhejiang Hainan biomaterial, Ltd.), 10 parts of SEBS (trade name G1657, Corteng Polymer Co., Ltd.), 6 parts of E-MA-GMA (trade name AX8900, Acoma group), 15 parts of talcum powder (trade name HTP1, Liaoning Aihai Talc Co., Ltd.), 0.2 parts of heat-resistant additive (0.1 part of antioxidant 1076, 0.1 part of antioxidant 168, Pasteur Corp.), and mixing in a high-speed mixer to obtain a mixture. And adding the mixture into a double-screw extruder for extrusion, cooling the extruded strips to room temperature through a circulating water tank, drying the extruded strips by a blower, and then granulating the dried extruded strips in a granulator to obtain the low-shrinkage high-toughness polypropylene composite material.

The length-diameter ratio of the double-screw extruder is 48:1, and the temperatures of all sections of a charging barrel of the double-screw extruder are respectively set as follows: 210 ℃ in the first zone, 220 ℃ in the second zone, 225 ℃ in the third zone, 230 ℃ in the fourth zone, 235 ℃ in the fifth zone, 240 ℃ in the sixth zone and 240 ℃ in the head. The product obtained in example 2 was tested for its properties according to the corresponding standards, the results of which are shown in table 1.

Example 3

49 parts of polypropylene (No. K7926, Shanghai Seiki petrochemical Co., Ltd.), 15 parts of polylactic acid (No. 3052D, Nature Works Co., U.S.), 5 parts of SEBS (No. 6150, Takeqi Co., Ltd.), 6 parts of E-MA-GMA (No. AX8900, Acoma group), 25 parts of talc (No. HTP1, Liaoning Aihai talc Co., Ltd.), 0.3 parts of heat-resistant auxiliary agent (0.1 part of antioxidant 1076, 0.2 part of antioxidant 168, Pasteur Co., Ltd.) were weighed and mixed in a high-speed mixer to obtain a mixture. And adding the mixture into a double-screw extruder for extrusion, cooling the extruded strips to room temperature through a circulating water tank, drying the extruded strips by a blower, and then granulating the dried extruded strips in a granulator to obtain the low-shrinkage high-toughness polypropylene composite material.

The length-diameter ratio of the double-screw extruder is 48:1, and the temperatures of all sections of a charging barrel of the double-screw extruder are respectively set as follows: 190 ℃ in the first zone, 200 ℃ in the second zone, 205 ℃ in the third zone, 210 ℃ in the fourth zone, 215 ℃ in the fifth zone, 220 ℃ in the sixth zone and 220 ℃ in the head. The product obtained in example 3 was tested for its properties according to the corresponding standards, the results of which are shown in table 1.

Example 4

Weighing 66 parts of polypropylene (No. K9829H, Beijing Yanshan petrochemical Co., Ltd.), 10 parts of polylactic acid (No. REVODE201 Zhejiang Haizian biomaterial Co., Ltd.), 5 parts of SEBS (No. G1657, Corteng Polymer Co., Ltd.), 4 parts of E-MA-GMA (No. AX8900, Akoma group), 15 parts of talcum powder (No. HTP1, Liaoning Aihai Talc Co., Ltd.), 0.4 parts of heat-resistant auxiliary agent (0.2 part of antioxidant 1010 and 0.2 part of antioxidant 168, Pasteur Co., Ltd.), and mixing in a high-speed mixer to obtain a mixture. And adding the mixture into a double-screw extruder for extrusion, cooling the extruded strips to room temperature through a circulating water tank, drying the extruded strips by a blower, and then granulating the dried extruded strips in a granulator to obtain the low-shrinkage high-toughness polypropylene composite material.

The length-diameter ratio of the double-screw extruder is 48:1, and the temperatures of all sections of a charging barrel of the double-screw extruder are respectively set as follows: 205 ℃ in the first zone, 215 ℃ in the second zone, 220 ℃ in the third zone, 225 ℃ in the fourth zone, 230 ℃ in the fifth zone, 230 ℃ in the sixth zone and 230 ℃ in the head. The product obtained in example 4 was tested for its properties according to the corresponding standards, the results of which are shown in table 1.

Comparative example 1

75 parts of polypropylene (trade name S2040, Shanghai Seiki petrochemical industry, Inc.), 25 parts of talcum powder (trade name HTP1, Liaoning Aihai talcum, Inc.), 0.3 part of heat-resistant auxiliary agent (0.1 part of antioxidant 1076, 0.2 part of antioxidant 168, Bassfu, Inc.) are weighed and put into a high-speed mixer to be mixed to obtain a mixture. And adding the mixture into a double-screw extruder for extrusion, cooling the extruded strips to room temperature through a circulating water tank, drying the extruded strips through a blower, and then granulating the extruded strips in a granulator.

The length-diameter ratio of the double-screw extruder is 48:1, and the temperatures of all sections of a charging barrel of the double-screw extruder are respectively set as follows: 190 ℃ in the first zone, 200 ℃ in the second zone, 205 ℃ in the third zone, 210 ℃ in the fourth zone, 215 ℃ in the fifth zone, 220 ℃ in the sixth zone and 220 ℃ in the head. The product obtained in comparative example 1 was tested for its properties according to the corresponding standards, the results of which are shown in table 1.

Comparative example 2

60 parts of polypropylene (trade name S2040, Shanghai Seisaku petrochemical industry, Ltd.), 15 parts of polylactic acid (trade name: REVODE201 Zhejiang Hainan biomaterial, Ltd.), 10 parts of SEBS (trade name G1657, Corteng Polymer Co., Ltd.), 15 parts of talcum powder (trade name HTP1, Liaoning Aihai talcum, Ltd.), 0.2 parts of heat-resistant auxiliary agent (0.1 part of antioxidant 1076, 0.1 part of antioxidant 168, Pasteur, Ltd.) were weighed and mixed in a high-speed mixer to obtain a mixture. And adding the mixture into a double-screw extruder for extrusion, cooling the extruded strips to room temperature through a circulating water tank, drying the extruded strips through a blower, and then granulating the extruded strips in a granulator.

The length-diameter ratio of the double-screw extruder is 48:1, and the temperatures of all sections of a charging barrel of the double-screw extruder are respectively set as follows: 210 ℃ in the first zone, 220 ℃ in the second zone, 225 ℃ in the third zone, 230 ℃ in the fourth zone, 235 ℃ in the fifth zone, 240 ℃ in the sixth zone and 240 ℃ in the head. The product obtained in comparative example 2 was tested for its properties according to the corresponding standards, the results of which are shown in table 1.

Comparative example 3

Weighing 66 parts of polypropylene (trade name S2040, Shanghai Seisaku petrochemical company, Ltd.), 15 parts of polylactic acid (trade name REVODE201, Zhejiang Haizian Liang Haizian biomaterial, Ltd.), 6 parts of E-MA-GMA (trade name AX8900, Acoma group), 15 parts of talcum powder (trade name HTP1, Liaoning Aihai Talc, Ltd.), 0.2 parts of heat-resistant auxiliary agent (0.1 part of antioxidant 1076, 0.1 part of antioxidant 168, Bassfu company), and mixing in a high-speed mixer to obtain a mixture. And adding the mixture into a double-screw extruder for extrusion, cooling the extruded strips to room temperature through a circulating water tank, drying the extruded strips by a blower, and then granulating the dried extruded strips in a granulator to obtain the low-shrinkage high-toughness polypropylene composite material.

The length-diameter ratio of the double-screw extruder is 48:1, and the temperatures of all sections of a charging barrel of the double-screw extruder are respectively set as follows: 210 ℃ in the first zone, 220 ℃ in the second zone, 225 ℃ in the third zone, 230 ℃ in the fourth zone, 235 ℃ in the fifth zone, 240 ℃ in the sixth zone and 240 ℃ in the head. The product obtained in comparative example 3 was tested for its properties according to the corresponding standards, the results of which are shown in table 1.

Comparative example 4

62 parts of polypropylene (trade name S2040, Shanghai Seiki petrochemical industry, Inc.), 10 parts of SEBS (trade name 6150, Tabbean, Inc.), 8 parts of E-MA-GMA (trade name AX8900, Acoma group), 20 parts of talcum powder (trade name HTP1, Liaoning Aihai talcum, Inc.), 0.4 parts of heat-resistant auxiliary agent (0.2 part of antioxidant 1010 and 0.2 part of antioxidant 168, Bassfu, Inc.) are weighed and put into a high-speed mixer to be mixed to obtain a mixture. And adding the mixture into a double-screw extruder for extrusion, cooling the extruded strips to room temperature through a circulating water tank, drying the extruded strips by a blower, and then granulating the dried extruded strips in a granulator to obtain the low-shrinkage high-toughness polypropylene composite material.

The length-diameter ratio of the double-screw extruder is 48:1, and the temperatures of all sections of a charging barrel of the double-screw extruder are respectively set as follows: 200 ℃ in the first zone, 210 ℃ in the second zone, 215 ℃ in the third zone, 220 ℃ in the fourth zone, 225 ℃ in the fifth zone, 230 ℃ in the sixth zone and 230 ℃ in the head. The product obtained in comparative example 4 was tested for its properties according to the corresponding standards, the results of which are shown in Table 1.

TABLE 1 Performance test results for products prepared in examples 1 to 4 and comparative examples 1 to 4

As can be seen from examples 1 to 4 and comparative examples 1 to 4, the polypropylene composite material prepared by the invention has low shrinkage, high toughness and high practical applicability.

The embodiments described above are intended to facilitate one of ordinary skill in the art in understanding and using the present invention. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the embodiments described herein, and those skilled in the art should make improvements and modifications within the scope of the present invention based on the disclosure of the present invention.