WO2023040756A1

WO2023040756A1 - Polypropylene composition and preparation method therefor

Info

Publication number: WO2023040756A1
Application number: PCT/CN2022/118016
Authority: WO
Inventors: 胡佳旭; 陈平绪; 叶南飚; 李伟; 俞飞; 吴国峰
Original assignee: 金发科技股份有限公司
Priority date: 2021-09-18
Filing date: 2022-09-09
Publication date: 2023-03-23
Also published as: CN113861566A

Abstract

The present invention relates to the technical field of polymers. Disclosed are a polypropylene composition and a preparation method therefor. According to the polypropylene composition of the present invention, HDPE having a specific density and talcum powder having a specific length-to-diameter ratio are added to a matrix as components, and the ratio of the components is optimized and selected. The high temperature bending strength of the obtained product is increased. The deformation amount at high temperature is reduced. The rigidity of the material is increased, and the molding cycle is significantly shortened. Also disclosed in the present invention is a preparation method for the polypropylene composition. The operation steps of the preparation method are simple, and large-scale industrial production can be realized. Also disclosed in the present invention is an application of HDPE in improving the performance of the polypropylene composition. Also disclosed in the present invention is an application of the polypropylene composition in the preparation of automobile and household appliance parts.

Description

A kind of polypropylene composition and preparation method thereof

technical field

The invention relates to the technical field of polymers, in particular to a polypropylene composition and a preparation method thereof.

Background technique

Polypropylene (PP) has the advantages of low density, easy processing, and excellent mechanical properties. It has been widely used in the automotive industry, home appliances, and machinery. For the automotive industry, polypropylene is mainly used in automotive interior and exterior parts such as instrument panels, door panels and pillars, as well as exterior parts such as bumpers, fenders, and deflectors. With the advancement of energy saving and emission reduction and automobile lightweight, new requirements are put forward for the molding cycle of polypropylene materials.

In order to reduce the molding cycle of polypropylene materials, people have carried out a lot of research, especially in the development and selection of high-crystalline polypropylene, as well as the development of new nucleating agents, and many other aspects have achieved good technological breakthroughs. At present, the newly developed thin-walled high-rigidity polypropylene has begun to be applied to parts such as automobile door panels, bumpers, and seat back panels. It has the characteristics of thin walls and short molding cycles. However, when such materials are applied to large parts such as bumpers, the molding cycle of ordinary injection molding machines is still difficult to exceed 40 seconds; in addition, due to the high temperature of the parts after molding, it is difficult for the robot to grasp the parts at this time, or The parts were severely deformed when placed on the trolley, resulting in the scrapping of the parts.

Contents of the invention

Based on the deficiencies of the prior art, the object of the present invention is to provide a polypropylene composition with short molding cycle and excellent deformation resistance at high temperature.

In order to achieve the above object, the technical scheme that the present invention takes is:

A polypropylene composition, comprising the following components in parts by weight: 51-65 parts of polypropylene resin, 12-22 parts of toughening agent, 5-10 parts of HDPE, 15-25 parts of talcum powder, and 0.1-0.4 parts of nucleating agent parts; the density of the HDPE is 0.955-0.962 g/cm ³ ; the aspect ratio of the talc powder is 6-15:1.

HDPE material itself has good flexibility, extensibility and impact resistance, and its chemical properties are stable, high temperature resistance, and good moisture resistance. After several experiments, the inventors of the present application found that adding HDPE with a specific density to the polypropylene composition can effectively improve the high-temperature deformation resistance of the overall material.

However, it is not that the more HDPE content is added, the better. The weight ratio of each component of the polypropylene composition of the present invention also has a greater impact on the final molding cycle of the product. When the HDPE content is low, the weight ratio of the polypropylene composition The molding cycle may not be significantly reduced, but when the HDPE content is high, it will lead to risks such as deformation of the part due to being too soft, increased post-shrinkage, and failure of the coating experiment. The inventors of the present application selected the ratio of each component, and the obtained formula ratio can increase the high-temperature bending strength of the polypropylene composition after adding HDPE, reduce the deformation of the material at high temperature, improve the rigidity of the material, and make the The polypropylene in the formula is well compatible with the toughening agent, and finally a polypropylene composition with better heat deformation resistance and short molding cycle is obtained.

Preferably, the weight part of the HDPE is 6-8 parts.

Preferably, the aspect ratio of the talc powder is 10-15:1.

The inventors of the present application have confirmed through multiple experiments that the polypropylene composition prepared with the HDPE of the density and the talc powder of the aspect ratio has the best comprehensive performance.

Preferably, the parts by weight of the talcum powder are 18 to 22 parts;

More preferably, the parts by weight of the talcum powder is 22 parts.

After talc powder is added to the polypropylene system as a filler at a specific aspect ratio, it can effectively form a cross-linked network with high mechanical resistance with the matrix and toughening agent, and when the filler is properly proportioned, it can To achieve the optimal balance of rigidity and toughness. When the added amount of talcum powder is 25 parts, the flexural modulus of the obtained polypropylene composition at room temperature can reach more than 2000MPa, and the impact strength can also reach more than 34KJ/ ^m2 ; however, the raw material cost of talcum powder is relatively high, and if adding Too much talcum powder will reduce the performance of the product again. Considering the degree of improvement of product performance by talcum powder, 18-22 phr is the most suitable addition.

Preferably, the mesh number of the talc powder is 3000-5000 mesh.

The talc powder with the particle size and mesh number has better dispersibility when added to the polypropylene material matrix, and the overall mechanical properties are the best.

Preferably, the polypropylene resin is a copolymerized polypropylene resin; the polypropylene has a melt mass flow rate (MFR) of 70-150 g/10 min at 230° C. and 2.16 kg tested according to the standard ASTM-D1238-13. Preferably, the toughening agent includes ethylene-octene copolymer, and the toughening agent is tested according to the standard ASTM-D1238-13, and the melt mass flow rate at 190° C. and 2.16 kg is 0.4˜6 g/10 min. Preferably, the HDPE is tested according to the standard ASTM-D1238-13, and the melt mass flow rate at 190°C and 2.16kg is 0.2-10g/10min, because the melt mass flow rate is mainly used to distinguish the polymer in the molten state Viscous flow characteristics, the combination of polypropylene resin, toughener and HDPE at the melt mass flow rate can make the finally prepared polypropylene composition have better mechanical effect. Preferably, the nucleating agent includes at least one of an arylamine nucleating agent and an aryl phosphate ester nucleating agent.

Preferably, the components of the polypropylene composition further include 0.1 to 3 parts of additives;

The auxiliary agents are antioxidants, light stabilizers and lubricants.

More preferably, the antioxidant is at least one of hindered phenolic antioxidant and phosphite antioxidant; the light stabilizer is hindered amine light stabilizer; the lubricant is monohard At least one of fatty acid glycerides and stearic acid metal salt compounds.

More preferably, the antioxidant is antioxidant 1010 (tetrakis [β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester), antioxidant 1076 (β-( 3,5-di-tert-butyl-4-hydroxyphenyl) n-octadecyl propionate), antioxidant 3114 (1,3,5-tri(3,5-di-tert-butyl-4-hydroxy benzyl) isocyanuric acid), antioxidant 168 (three [2.4-di-tert-butylphenyl] phosphite), at least one of PEP-36; the light stabilizer is UV-3808PP5, LA- At least one of 402XP and LA-402AF; the lubricant is at least one of calcium stearate and magnesium stearate.

The addition of antioxidants, light stabilizers and lubricants under the above categories can effectively ensure the stability and usability of the polypropylene composition, avoid changes in material properties due to the influence of external conditions, and ultimately affect the quality of the polypropylene composition. Use performance.

Another object of the present invention is also to provide a preparation method of the polypropylene composition, comprising the following steps:

After mixing polypropylene resin, toughening agent, HDPE, talc powder, nucleating agent and auxiliary agent in proportion, put them into a twin-screw extruder, melt and knead, extrude and granulate to obtain the polypropylene combination.

The preparation method of the polypropylene composition of the invention has simple operation steps and can realize large-scale industrial production.

Preferably, the melting and mixing temperature is 170-220° C., and the screw speed in the twin-screw extruder is 350-450 rpm. Under said conditions, the melt mixing of each composition is more uniform.

Another object of the present invention is to provide the use of HDPE in the preparation of the polypropylene composition of the present invention.

The polypropylene composition of the present invention prepared with HDPE as a component has the effects of short molding cycle and high temperature resistance to deformation.

Another object of the present invention is to provide the application of the polypropylene composition in the preparation of automobile and home appliance parts.

The polypropylene composition obtained by the invention has a short molding cycle and strong high-temperature deformation resistance, and is suitable for the preparation of various parts and parts of automobiles and household appliances with special processing requirements.

The beneficial effect of the present invention is that: the present invention provides a polypropylene composition, which adds HDPE of specific density and talcum powder of specific aspect ratio in the matrix as components, and at the same time, the ratio of each component Through optimization selection, under the premise of maintaining good mechanical properties at room temperature, the bending modulus at high temperature increases, the deformation of the material at high temperature decreases, the thermal stability of the material improves, and the molding cycle is significantly shortened. The invention also provides a preparation method of the polypropylene composition. The preparation method has simple operation steps and can realize large-scale industrial production. The present invention also provides the use of HDPE for improving the properties of polypropylene compositions. The invention also provides the application of the polypropylene composition in the preparation of automobile and household appliance parts.

Detailed ways

In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific examples, the purpose of which is to understand the content of the present invention in detail, rather than limit the present invention.

Unless otherwise specified, the raw materials used in the following specific examples are commercially available common goods.

Examples 1-10

Examples of the polypropylene composition of the present invention, the component formulations of the products described in each example are shown in Table 1.

The preparation method of the polypropylene composition described in each embodiment is identical, and described preparation method is:

After mixing polypropylene resin, toughening agent, HDPE, talcum powder, nucleating agent and auxiliary agent in high-speed mixer for 30s, transfer to twin-screw extruder and carry out melting mixing, the temperature of described melting mixing is 200° C., the screw speed is 400 rpm, and then extruded and granulated to obtain the polypropylene composition.

Example 11

The difference between this example and Example 4 is that the aspect ratio of the talc powder is 8:1; the mesh number of the talc powder is 3500 mesh, and the product is produced by Liaoning Aihai Talc Company.

Example 12

The difference between this example and Example 4 is that the polypropylene resin is a copolymerized polypropylene resin produced by SK Company in Korea, and the melt mass flow rate at 230° C. and 2.16 kg is 60 g/10 min.

Example 13

The difference between this embodiment and Example 4 is that the toughening agent is an ethylene octene copolymer produced by Dow Chemical Company of the United States; the melt mass flow rate of the toughening agent at 190 ° C and 2.16 kg is 8g/10min.

Comparative example 1

The difference between this comparative example and Example 4 is that the density of the HDPE is 0.950g/cm ³ ; the melt mass flow rate of the HDPE at 190°C and 2.16kg is 10g/min, a product produced by Fujian United Petrochemical Co., Ltd. .

Comparative example 2

The only difference between this comparative example and Example 4 is that the HDPE is replaced by MDPE, and the density of the MDPE is 0.940 g/cm ³ , which is produced by Fujian United Petrochemical.

Comparative example 5

The only difference between this comparative example and Example 4 is that the aspect ratio of the talcum powder is 5:1.

Comparative example 9

The only difference between this comparative example and Example 4 is that the aspect ratio of the talcum powder is 16:1.

In addition to the above differences, the only difference between the polypropylene compositions described in Comparative Examples 1-11 and Examples 1-13 lies in the composition ratio of the components. The composition formulations of the products described in each Comparative Example are shown in Table 2.

In each component of described table 1, table 2, except the different component raw materials that above-mentioned difference adopts, other identical components used are as follows:

The polypropylene resin is a copolymerized polypropylene resin produced by SK Company in South Korea, and its melt mass flow rate at 230°C and 2.16kg is 105g/10min;

The toughening agent is an ethylene-octene copolymer produced by Dow Chemical Company of the United States; the melt mass flow rate of the toughening agent at 190 ° C and 2.16 kg is 5 g/10 min;

The HDPE is HDPE produced by Fujian United Petrochemical; the density of the HDPE is 0.957g/cm ³ ; the melt mass flow rate of the HDPE at 190°C and 2.16kg is 8g/10min;

Described nucleating agent is the NA-11 model aryl phosphate nucleating agent produced by Aidike;

The talcum powder is a product produced by Liaoning Aihai Talc Company, the aspect ratio of the talcum powder is 12:1, and the mesh number of the talcum powder is 3000 mesh;

Described antioxidant is the antioxidant compound that antioxidant 1010 and antioxidant 168 are compounded by mass ratio 1:1, all are the products produced by U.S. BASF;

Described light stabilizer is UV-3808PP5, the product produced by Cytec Chemical;

Described lubricant is calcium stearate, the product produced by Jiangxi Hongyuan Chemical Co., Ltd.

Table 1

Table 2

table 3

Table 4

In order to verify the performance of the product of the embodiment of the present application, each embodiment and comparative products are subjected to a performance test, and the test results are shown in Table 3 and Table 4; the tensile strength of the product is according to the ISO 527-2019 test method, The Zwick Z005 electronic universal testing machine is used for testing; the flexural modulus of the product is tested by the Zwick Z005 electronic universal testing machine according to the ISO 178-2019 test method; the high temperature and high temperature flexural modulus of the product is tested by the ISO178-2019 test method; The impact strength of said product is Charpy notched impact strength, and said impact strength adopts Zwick HIT5.5P electronic display impact instrument test according to ISO179-2000 method; *Thickness = 220*50*2mm) One end is fixed on the fixture, and the other end leaks out of the fixture. The size of the fixture is 150mm. Measure the height of the test piece from the bottom of the fixture, and then heat the fixture and test piece in an oven at 120°C for 1 hour Finally, measure the height of the test piece from the bottom of the fixture to calculate the deformation of the test piece after heating, that is, thermal sag; the molding cycle of the product is actually tested by forming the test plate.

It can be seen from Table 3 and Table 4 that the polypropylene composition obtained in the embodiment of the present invention has excellent mechanical properties compared with the composition product obtained in the comparative example, its tensile strength is ≥ 17.5MPa, and the flexural modulus is > 1500MPa , the impact strength can reach 30KJ/m ² ; and the deformation resistance at high temperature is also significantly improved, the flexural modulus can be kept above 520MPa at 80°C, the thermal sag is less than 6.5mm, and the molding cycle is shortened to less than 40s, indicating that HDPE components The addition of the product can effectively improve the high-temperature deformation resistance of the product. It can be demoulded at a higher temperature, rapid prototyping, and prevents deformation during storage. It is effectively used in the preparation of parts with special requirements.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that The technical solution of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solution of the present invention.

Claims

A polypropylene composition, characterized in that it comprises the following components in parts by weight: 51-65 parts of polypropylene resin, 12-22 parts of toughening agent, 5-10 parts of HDPE, 15-25 parts of talcum powder, nucleating 0.1-0.4 part of agent; the density of the HDPE is 0.955-0.962g/cm 3 ; the aspect ratio of the talcum powder is 6-15:1.
The polypropylene composition according to claim 1, wherein the HDPE is tested according to standard ASTM-D1238-13, and has a melt mass flow rate of 0.2-10 g/10 min at 190° C. and 2.16 kg.
The polypropylene composition according to claim 1, wherein the aspect ratio of the talc powder is 10-15:1.
The polypropylene composition according to claim 1, wherein the talcum powder has 18-22 parts by weight.
The polypropylene composition according to claim 1, wherein the polypropylene resin has a melt mass flow rate of 70-150 g/10 min at 230° C. and 2.16 kg tested according to the standard ASTM-D1238-13.
The polypropylene composition according to claim 1, wherein the toughening agent is tested according to the standard ASTM-D1238-13, and the melt mass flow rate at 190°C and 2.16kg is 0.4-6g/10min.
The polypropylene composition according to claim 1, characterized in that, the components of the polypropylene composition also include 0.1 to 3 parts of auxiliary agents, and the auxiliary agents are antioxidants, light stabilizers and lubricants; Preferably, the antioxidant is at least one of a hindered phenolic antioxidant and a phosphite antioxidant; the light stabilizer is a hindered amine light stabilizer; the lubricant is monostearin At least one of glyceryl acid esters and stearic acid metal salt compounds.
The preparation method of the polypropylene composition according to any one of claims 1 to 7, characterized in that it comprises the following steps:

After mixing polypropylene resin, toughening agent, HDPE, talc powder, nucleating agent and auxiliary agent in proportion, put them into a twin-screw extruder, melt and knead, extrude and granulate to obtain the polypropylene Composition; preferably, the melting and mixing temperature is 170-220° C., and the screw speed in the twin-screw extruder is 350-450 rpm.
An application of HDPE in the preparation of the polypropylene composition according to any one of claims 1-7.
The application of the polypropylene composition according to any one of claims 1 to 7 in the preparation of automobile and household appliance parts.