Impact-resistant glass fiber reinforced polypropylene material as well as preparation method and application thereof

Abstract

The invention relates to an anti-impact glass fiber reinforced polypropylene material and a preparation method and application thereof in the field of plastic processing. The impact-resistant glass fiber reinforced polypropylene material mainly comprises the following components: polypropylene resin, long glass fiber reinforced polypropylene, a flexibilizer, a compatilizer and polyethylene, the total weight of the main materials is 100 parts by weight, and the use amounts of the components are as follows: 10-55 parts by weight of long glass fiber reinforced polypropylene, 1-10 parts by weight of a flexibilizer, 1-7 parts by weight of a compatilizer, 0-5 parts by weight of polyethylene and 36-75 parts by weight of polypropylene resin. The impact-resistant glass fiber reinforced polypropylene material disclosed by the invention has stress whitening resistance, scratch resistance and excellent processability and mechanical properties. The method can be applied to industries such as automobiles, household appliances and bags.

Description

Technical Field

[0001] The present invention relates to the field of plastic processing. More specifically, it relates to an impact-resistant glass fiber-reinforced polypropylene material, its preparation method and application. Background Art

[0002] Polypropylene itself has the characteristics of being brittle at low temperatures, having a large molding shrinkage rate, insufficient wear resistance, a low heat distortion temperature, and poor aging resistance. To improve the deficiencies of polypropylene, people mainly adopt two major methods: copolymer modification and blending modification. The former is to introduce a comonomer and control the polymerization process, and the latter is to blend with rubber, plastics, fillers, nucleating agents, etc. Glass fiber-reinforced polypropylene is a modified polypropylene material that emerged in the 1940s. Since its emergence, it has been widely used in industries such as power tools, household appliances, and automobiles with excellent performance.

[0003] With the development of the times, the maturity and popularization of various modification technologies, while meeting the product requirements, manufacturers have pursued and regarded the product appearance and the maintenance of the appearance under external forces during use as favorable competitive factors, which have been sought after by major user enterprises. Among them, relatively prominent properties include: scratch resistance, matting, high gloss, etc. Among them, during the use of long glass fiber-reinforced polypropylene products, when they are impacted by external forces, stress whitening occurs, which affects the appearance of the products.

[0004] The so-called "stress whitening" refers to the phenomenon that local whitening occurs in polymer materials under stress. Stress whitening is the result of the generation of a large number of microcrack aggregation areas (depending on the degree and occurrence area of stress whitening, it may include a certain number of crazes, cracks, and micropores) in the material under stress. Due to the decrease in density and refractive index in this area, birefringence occurs and it appears white; stress whitening is the result of the generation of microcracks, crazing, and cavitation. Summary of the Invention

[0005] In order to solve the above problems existing in the prior art, the present invention proposes an impact-resistant glass fiber-reinforced polypropylene material. Specifically, it relates to an impact-resistant glass fiber-reinforced polypropylene material, its preparation method and application. The content of the present invention relates to the solution to the problem that stress whitening occurs when long glass fiber-reinforced polypropylene products are impacted by external forces during use, which affects the appearance of the products. The present invention takes the principle of stress whitening generation as the solution and research direction, and can adjust the formula and preparation process according to the actual use environment of the products. While solving the stress whitening problem, the formula can also be adjusted according to needs to solve performance requirements such as aging resistance, scratch resistance, low odor, and heat resistance.

[0006] On the other hand, glass fiber reinforced polypropylene is a polypropylene reinforcing material. Currently, glass fiber reinforced polypropylene is mainly divided into chopped glass fiber, glass fiber, and long glass fiber. The essential purpose of adding glass fiber is to enhance the reinforcement effect. When other influencing factors are the same, the retained length of the glass fiber determines the reinforcement effect. Among the three types of glass fibers, the retained length of the long glass fiber is the largest. In the case of using a large gate injection, it can reach 3 - 6 mm, which has exceeded the critical length and should have a good reinforcement effect. However, the inventors of this application found in a large number of actual applications that although its tensile strength and flexural strength have been greatly improved, the impact strength under conditions closer to actual use is very low. Using ISO 6603 - 2:2000(E) as the test standard and an INSTRON9450 instrumented impact tester to test the impact performance of long glass fiber reinforced polypropylene with 20%, 30%, 40%, and even 50% long glass fiber content, the test results are all very low, resulting in damage, and all are brittle fractures, and even delamination phenomena occur. For example, see Figure 1 (Impact performance test diagram of 50% long glass fiber content glass fiber reinforced polypropylene). This is determined by the current conventional production method of long glass fiber reinforced polypropylene. The practical value of such long glass fiber reinforced polypropylene is very low.

[0007] Considering the above situation, one aspect of the invention content of the present invention focuses on the improvement of stress whitening performance, and on the other hand, also pays attention to the actual application performance of this long glass fiber reinforced polypropylene.

[0008] One of the purposes of the present invention is to provide an impact-resistant glass fiber reinforced polypropylene material, and its main materials may include the following components blended: polypropylene resin, long glass fiber reinforced polypropylene, toughening agent, compatibilizer, optional polyethylene; based on 100 parts by weight of the total weight of the main materials,

[0009] The dosage of each component can be as follows:

[0010] Long glass fiber reinforced polypropylene 10 - 55 parts by weight, preferably 20 - 52 parts by weight,

[0011] Toughening agent 1 - 10 parts by weight, preferably 3 - 8 parts by weight,

[0012] Compatibilizer 1 - 7 parts by weight, preferably 2 - 5 parts by weight,

[0013] Polyethylene 0 - 5 parts by weight, preferably 0 - 4 parts by weight,

[0014] Polypropylene resin 36 - 75 parts by weight, preferably 38 - 73 parts by weight.

[0015] Among them,

[0016] The dosage of the long glass fiber reinforced polypropylene may specifically be 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 24, 25, 27, 30, 32, 35, 37, 39, 40, 42, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55 parts by weight, or any value between the above values, or a numerical range between any two of the above values, such as 15 to 52 parts, etc.

[0017] The long glass fiber reinforced polypropylene is produced by using an impregnation device for continuous fiber reinforced thermoplastic materials.

[0018] Specifically, the long glass fiber reinforced polypropylene may be the long glass fiber reinforced polypropylene composite material disclosed in the Chinese patent with the publication number CN114479283A (application number: 202011163308.X, subject name: A long glass fiber reinforced polypropylene composite material and its preparation method and application). The entire content of the Chinese patent with the publication number CN114479283A (application number: 202011163308.X, subject name: A long glass fiber reinforced polypropylene composite material and its preparation method and application) is hereby incorporated by reference.

[0019] Specifically, the long glass fiber reinforced polypropylene may be made from the following components in parts by weight:

[0020] 100 parts of polypropylene for impregnation;

[0021] 3 - 15 parts of compatibilizer composition; preferably 3 - 10 parts;

[0022] 20 - 60 parts of glass fiber; preferably 30 - 50 parts;

[0023] 3 - 25 parts of surface modifier; preferably 5 - 10 parts;

[0024] The polypropylene for impregnation has a melt flow rate of 40 - 150 g / 10 min, preferably 100 - 150 g / 10 min, at 230°C under a load of 2.16 kg;

[0025] The compatibilizer composition comprises a combination of maleic anhydride grafted polypropylene and bisphenol A diglycidyl ether; wherein the weight ratio of maleic anhydride grafted polypropylene to bisphenol A diglycidyl ether is 1:2 - 5:1;

[0026] The glass fiber is an alkali - free high - strength continuous glass fiber with a strength > 2300 MPa, a diameter of 10 - 24 μm, and a linear density of 1200 - 4800 TEX;

[0027] The surface modifier described above is ultra-high melt index polypropylene; preferably, the ultra-high melt index polypropylene has a melt flow rate of 150 to 10,000 g / 10 min, preferably 400 to 3,800 g / 10 min (under the conditions of 230 °C and a load of 2.16 kg).

[0028] The dosage of the toughening agent contained in the impact-resistant glass fiber-reinforced polypropylene material described in this application can specifically be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 parts by weight or any value between the above values or the numerical range between any two of the above values.

[0029] The toughening agent contained in the impact-resistant glass fiber-reinforced polypropylene material described in this application can be selected from SEBS. Specifically, it can be, for example, the SEBS of the YH series produced by Yueyang Petrochemical. Generally speaking, the compatibility between SEBS and polypropylene is good, resulting in a general toughening effect. The reason for selecting SEBS as the toughening agent in this application is mainly that the larger the sample particle size, the more obvious the tendency to form silver streaks, while the small particle size of SEBS rubber particles can effectively improve the stress whitening resistance of the product and at the same time have a certain impact resistance. The small rubber particle size induces the generation of a stress enhancement zone, thus not effectively triggering silver streaks.

[0030] The dosage of the compatibilizer contained in the impact-resistant glass fiber-reinforced polypropylene material described in this application can specifically be 1, 2, 3, 4, 5, 6, 7 parts by weight or any value between the above values or the numerical range between any two of the above values.

[0031] The compatibilizer contained in the impact-resistant glass fiber-reinforced polypropylene material described in this application can be selected from one or a compound of two of grafted POE, grafted ethylene-propylene rubber, and grafted PE. The main purpose is to increase the adhesion between the glass fiber and the polypropylene substrate, thereby reducing the phenomenon of the glass fiber being pulled out during impact and enabling the glass fiber to truly play a reinforcing role. It can also be considered that a toughening agent with a large rubber particle size is added, and the toughening effect is higher than that of SEBS, which has a certain degree of reduction in the stress whitening resistance of the product. Therefore, considering the product performance comprehensively, it is preferably added.

[0032] The dosage of the polyethylene (PE) contained in the impact-resistant glass fiber-reinforced polypropylene material described in this application can specifically be 0, 1, 2, 3, 4, 5 parts by weight or any value between the above values or the numerical range between any two of the above values.

[0033] The polyethylene (PE) contained in the impact-resistant glass fiber-reinforced polypropylene material described in this application may be selected from at least one of HDPE, LDPE, and LLDPE. The melt index of the polyethylene may specifically be 0.5 to 10 g / 10 min (under the conditions of 190 °C and a load of 2.16 kg). Among them, the melt index may specifically be 0.5, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0 g / 10 min or any value between the above values or the numerical range between any two of the above values. When the polypropylene melt cools, the matrix crystallization squeezes the dispersed phase, and the crystallization of the ethylene sequence in the dispersed phase will produce a relaxation effect on the rubber particles, reducing the freezing stress of the polypropylene, thereby reducing the crazing generated by impact and improving the stress whitening resistance.

[0034] The amount of the polypropylene resin contained in the impact-resistant glass fiber-reinforced polypropylene material described in this application may specifically be 36, 37, 38, 39, 40, 42, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 57, 59, 60, 62, 64, 66, 68, 70, 71, 72, 73, 74, 75 parts by weight or any value between the above values or the numerical range between any two of the above values.

[0035] The polypropylene resin contained in the impact-resistant glass fiber-reinforced polypropylene material described in this application may be a homopolymer or copolymer polypropylene with a melt index of 3 to 50 g / 10 min (under the conditions of 230 °C and a load of 2.16 kg). Among them, the melt index may specifically be 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 17, 18, 20, 22, 24, 25, 27, 28, 30, 32, 34, 36, 37, 38, 39, 40, 42, 45, 46, 47, 48, 49, 50 g / 10 min or any value between the above values or the numerical range between any two of the above values.

[0036] Specifically,

[0037] The impact-resistant glass fiber-reinforced polypropylene material may further contain a nucleating agent;

[0038] The addition of the nucleating agent can greatly reduce the crystal size while increasing the crystallinity. When damaged by external impact, the energy absorption mode changes from mainly multiple crazes to mainly shear yielding or shear yielding containing voids and secondary cracks, thereby reducing stress whitening.

[0039] The nucleating agent described in the present application can specifically be selected as α-type nucleating agents, and can specifically be selected from the conventional types of α-type nucleating agents, such as NA21, NA11, HPN-20E, 3988, NX8000, HPN-68L9 (Milliken & Company), etc. According to our experiments, β-type nucleating agents will deteriorate the stress whitening resistance of the product, probably due to crystal form transformation.

[0040] Polypropylene is a typical crystalline polymer. Since the molecular chains are linked by covalent bonds within the molecule and interact with each other by van der Waals forces between molecules, it cannot move freely during crystallization, which hinders its stacking arrangement, resulting in partial crystallization with many distorted lattices and defects. The addition of a nucleating agent can perfect the crystallization and increase the crystallinity of the material. While improving the stress whitening resistance of the product, it also improves the strength and heat resistance of the product.

[0041] Preferably, based on 100 parts by weight of the amount of the main material, the amount of the nucleating agent can be 0.02 to 1.5 parts by weight, preferably 0.05 to 1 part by weight.

[0042] Specifically, the impact-resistant glass fiber-reinforced polypropylene material described in the present application may further contain a lubricant. The addition of the lubricant can improve the processing performance and the surface, and most importantly, it has a great effect on the recovery after stress whitening occurs. The lubricant in the present application is specifically selected from at least one of lubricant 1 and lubricant 2. Lubricant 1 can be erucamide; lubricant 2 can be a masterbatch for scratch-resistant polypropylene, specifically a masterbatch prepared by the Chinese patent with the publication number CN102924773A (application number: CN201110226099.3, theme name: a scratch-resistant polypropylene masterbatch and its preparation method). The applicant has found that lubricant 2 can also effectively improve fiber exposure. The entire content of the Chinese patent with the publication number CN102924773A (application number: CN201110226099.3, theme name: a scratch-resistant polypropylene masterbatch and its preparation method) is hereby incorporated by reference in its entirety. Each of the two lubricants has its own advantages and disadvantages, and can be selected according to the actual cost and performance requirements.

[0043] Specifically, the scratch-resistant polypropylene masterbatch may comprise the following blended components: polyolefin resin, lubricant 3; wherein, based on 100 parts by weight of the polyolefin resin, the dosage of lubricant 3 is 10 to 70 parts by weight; the polyolefin resin is selected from polyethylene for masterbatch and / or polypropylene for masterbatch, and a composition of grafted polyethylene for masterbatch; the lubricant 3 includes a main lubricant and an auxiliary lubricant; the main lubricant is silicone powder, and the auxiliary lubricants are methyl silicone oil and polypropylene wax; the compounding ratio of the silicone powder, methyl silicone oil and polypropylene wax is 100:(3 - 5):(5 - 7) by weight. In the polyolefin resin, the grafted polyethylene for masterbatch is 30 to 60 wt%, and the balance is polyethylene for masterbatch and / or polypropylene for masterbatch; wherein, the grafted polyethylene for masterbatch is selected from high-density polyethylene with an MI of 10 to 100 g / 10 min (19)℃, 2.16 Kg) and a grafting rate of 1 to 2%; the polyethylene for masterbatch is selected from high-density polyethylene and / or low-density polyethylene with an MI of 20 to 100 g / 10 min (190℃, 2.16 Kg); the polypropylene for masterbatch is selected from homopolymerized and / or copolymerized polypropylene with an MI of 20 to 100 g / 10 min (230℃, 2.16 Kg).

[0044] Regarding the lubricant of the impact-resistant glass fiber-reinforced polypropylene material described in the present application,

[0045] Preferably, when the lubricant is erucamide (lubricant 1), the dosage of polyethylene in the main material is not 0;

[0046] Preferably, based on 100 parts by weight of the main material, the dosage of lubricant 1 can be 0.4 to 1.2 parts by weight, preferably 0.5 to 1.0 parts by weight;

[0047] Preferably, based on 100 parts by weight of the main material, the dosage of lubricant 2 can be 1 to 8 parts by weight, preferably 3 to 6 parts by weight.

[0048] The present invention may add a color masterbatch as needed, and the specific dosage can be added according to the conventional color matching ratio.

[0049] The color masterbatch can be a conventional color masterbatch. For example, a conventional color masterbatch with a ratio of 1:50 can be used, and the dosage can be adjusted according to the actual situation. The color masterbatch can be various colors such as beige, gray, black, white, etc. In addition, since the color difference is specifically used to evaluate the stress whitening resistance performance, there will be a great difference between materials dyed with dark and light color masterbatches. Therefore, a unified color color masterbatch, such as a dark gray color masterbatch, is used in the specific evaluation of the stress whitening resistance performance for convenient evaluation.

[0050] Other conventional additives can also be added according to specific requirements. Antioxidants, light stabilizers, etc. are all conventional varieties and conventional addition amounts. For example, based on 100 parts by weight of the main material, the dosage can be 0.1 - 2 parts by weight, and the specific addition and dosage adjustment can be carried out conventionally according to needs.

[0051] The second object of the present invention is to provide a preparation method of the impact-resistant glass fiber reinforced polypropylene material described in the first object of the present invention, which may include the following steps:

[0052] The components including the polypropylene, toughening agent, compatibilizer, optional nucleating agent, optional lubricant, optional polyethylene PE (if lubricant 2 is selected, it may not be added), optional color masterbatch, and optional antioxidant are melt-blended to obtain a modified polypropylene material, and the modified polypropylene material is processed and formed with the long glass fiber reinforced polypropylene to obtain the impact-resistant long glass fiber reinforced polypropylene material. The device used for processing and forming can be an injection molding machine.

[0053] In specific practice, the preparation method may include the following steps:

[0054] 1. The components including the polypropylene, toughening agent, compatibilizer, optional nucleating agent, optional lubricant, optional polyethylene PE (if lubricant 2 is selected, it may not be added), optional color masterbatch, and optional antioxidant are blended evenly according to the dosage and melt-blended through equipment to obtain a modified polypropylene material, that is, component A;

[0055] Preferably, the vacuum degree during melt-blending is maintained higher than -0.08 MPa;

[0056] Preferably, the blending temperature can be 190 - 230 °C.

[0057] In the preparation method, various mixing equipment used in the prior art can be adopted for material mixing, such as mixers, kneaders, etc. The melt-blending equipment used in the method of the present invention is a general melt-blending equipment in the rubber and plastics processing industry, for example, it can be a twin-screw extruder, a BUSS mixing unit, etc.

[0058] 2. Prepare long glass fiber reinforced polypropylene, that is, component B; the equipment for preparing the long glass fiber can be selected from impregnation equipment, dispersion roller systems, preheating units, pelletizers, and other equipment.

[0059] 3. According to the actual required glass fiber content, the modified polypropylene and the long glass fiber reinforced polypropylene are blended in proportion to obtain the impact-resistant long glass fiber reinforced polypropylene material. In this application, an injection molding machine can be specifically used. Adding directly in the injection stage can ensure the accuracy of the glass fiber content. Moreover, compared with equipment such as twin-screws, the injection molding machine has a low shear strength, which can ensure the retention length of the glass fiber.

[0060] A third object of the present invention is to provide an impact-resistant glass fiber-reinforced polypropylene material described in the first object of the present invention or an application of the impact-resistant glass fiber-reinforced polypropylene material prepared by the preparation method described in the second object of the present invention, preferably in the fields of automobiles and household appliances.

[0061] In the present application, by means of blending modification, the size of crack micropores or silver streaks generated when the product is impacted is reduced, so as to achieve an improvement in stress whitening resistance. The impact-resistant glass fiber-reinforced polypropylene material of the present invention has stress whitening resistance, scratch resistance, excellent processing performance and mechanical properties, and excellent heat and light aging resistance.

[0062] For the described impact-resistant long glass fiber-reinforced polypropylene material, the glass fiber content can be flexibly adjusted. Through large-gate injection, it can ensure that the glass fiber length in the product exceeds the critical glass fiber length. It has excellent comprehensive mechanical properties, appearance properties, stress whitening resistance, and scratch resistance. It can be applied to industries such as automobiles, household appliances, and luggage. Description of the Drawings

[0063] Figure 1 It is a test chart of the impact performance of glass fiber-reinforced polypropylene with a 50% long glass fiber content. Detailed Embodiments

[0064] The present invention will be specifically described below in conjunction with specific embodiments. It is necessary to point out here that the following embodiments are only for further illustration of the present invention and cannot be understood as limiting the protection scope of the present invention. Some non-essential improvements and adjustments made by those skilled in the art to the present invention based on the content of the present invention still fall within the protection scope of the present invention.

[0065] For the endpoints and any values disclosed in the ranges in this article, they are not limited to the exact ranges or values. These ranges or values should be understood to include values close to these ranges or values. For numerical ranges, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values, they can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed in this article.

[0066] Source of Raw Materials

[0067] For the raw materials used in the examples and comparative examples, if not specifically defined, they are all disclosed in the prior art. For example, they can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0068] Examples 1 to 8 and Comparative Examples 1 to 3:

[0069] Example 1

[0070] PP resin (Borealis, grade 10058, copolymerized polypropylene, melt index 20 g / 10 min (at 230 °C and a load of 2.16 kg)), toughening agent (SEBS, Yueyang Petrochemical, YH-503), compatibilizer (grafted POE, 493D from DOW Chemical Company), lubricant (erucamide, Jiangxi Zhilian Plastic Technology Co., Ltd.), antioxidant (BASF China Co., Ltd., hindered phenolic antioxidant irganox B225), PE (Shanghai Petrochemical, DJ200, cable grade LDPE, melt index 2.0 g / 10 min (at 190 °C and a load of 2.16 kg)), nucleating agent (Asahi Denka Co., Ltd., NA11), and masterbatch (Beijing Clariant Masterbatch Co., Ltd., dark gray, 1:50) were added to a high-speed mixer and stirred evenly. Subsequently, the above-mentioned mixed materials were pelletized by a twin-screw mixing extruder. The mixing temperature was 190 - 230 °C, and the vacuum degree of the equipment vacuum system was maintained above -0.08 MPa; thus, the impact-resistant glass fiber-reinforced polypropylene material component A (modified polypropylene material) was prepared. The specific formulation is shown in Table 1.

[0071] (The preparation of component A in other examples and comparative examples is similar. For the component changes in the following examples and comparative examples, only the changed parts are marked.)

[0072] The impact-resistant glass fiber-reinforced polypropylene material component B (long glass fiber-reinforced polypropylene) was prepared according to the preparation method in Example 5 of the published text specification of the Chinese patent with the publication number CN114479283A (glass fiber content 50%).

[0073] The prepared impact-resistant long glass fiber-reinforced polypropylene material component A was dried in a 90 °C cyclone drying oven for 2 h; the prepared impact-resistant glass fiber-reinforced polypropylene material component B was dried in a 90 °C cyclone drying oven for 4 h; and then injection molding was carried out using an injection molding machine (Ningbo Haitian Plastic Machinery Group Co., Ltd., MA900) for testing.

[0074] Example 2

[0075] The only difference from Example 1 is: the type of compatibilizer is different. The compatibilizer used in this example is grafted ethylene-propylene rubber (Compton Corporation, USA, 498). All other steps are the same as in Example 1. The specific formulation is shown in Table 1.

[0076] Example 3

[0077] The only difference from Example 1 is: the type of compatibilizer is different. The compatibilizer used in this example is grafted PE (Puli Hongbin Company). All other steps are the same as in Example 1. The specific formulation is shown in Table 1.

[0078] Example 4

[0079] The differences from Example 2 are as follows: the glass fiber content is different, and the types of lubricants are different. The lubricant used in this example is a polypropylene scratch-resistant masterbatch, specifically the scratch-resistant masterbatch 1 prepared by the method of Example 1 of the Chinese patent with the publication number CN102924773A. Other steps are the same as those in Example 2.

[0080] Example 5

[0081] The only difference from Example 2 is as follows: the masterbatch is different. The masterbatch used in this example is beige. Other steps are the same as those in Example 2. Its specific formulation is shown in Table 1.

[0082] Examples 6 - 8

[0083] The only difference from Example 4 is as follows: the glass fiber content is different. Other steps are the same as those in Example 4. Its specific formulation is shown in Table 1.

[0084] Comparative Example 1

[0085] Add PP resin (Borealis, grade 10058), antioxidant (BASF China Co., Ltd., hindered phenolic antioxidant irganox B225), and masterbatch (Clariant Masterbatch Co., Ltd., Beijing, dark gray, 1:50) to a high-speed mixer and stir evenly. Subsequently, granulate the above mixed materials through a twin-screw mixing unit. The mixing temperature is 190 - 230°C, and maintain the vacuum degree of the equipment vacuum system higher than -0.08 MPa; thus, the impact-resistant glass fiber-reinforced polypropylene material component A is obtained. Its specific formulation is shown in Table 1.

[0086] Dry the impact-resistant long glass fiber-reinforced polypropylene material component A prepared above in a 90°C cyclone drying oven for 2 h; dry the impact-resistant glass fiber-reinforced polypropylene material component B (prepared by the same method as in Example 1) in a 90°C cyclone drying oven for 4 h and then perform injection molding tests using an injection molding machine (Ningbo Haitian Plastic Machinery Group Co., Ltd., MA900).

[0087] Comparative Example 2

[0088] PP resin (Borealis, grade 10058), toughening agent (SEBS, Yueyang Petrochemical, YH-503), lubricant (erucamide, Jiangxi Zhilian Plastic Technology Co., Ltd.), antioxidant (BASF China Co., Ltd., hindered phenolic antioxidant irganoxB225), PE (Shanghai Petrochemical, 200J), nucleating agent (Asahi Denka Co., Ltd., NA11), and masterbatch (Beijing Clariant Masterbatch Co., Ltd., dark gray, 1:50) were added to a high-speed mixer and stirred evenly. Subsequently, the above-mentioned mixed materials were pelletized by a twin-screw mixing extruder, and the mixing temperature was 190-230 °C, keeping the vacuum degree of the equipment vacuum system higher than -0.08 MPa; the impact-resistant glass fiber-reinforced polypropylene material component A was prepared. Its specific formulation is shown in Table 1.

[0089] The preparation method of the impact-resistant glass fiber-reinforced polypropylene material component B (long glass fiber-reinforced polypropylene) was prepared by the same method as in Example 1.

[0090] The prepared impact-resistant long glass fiber-reinforced polypropylene material component A was dried in a 90 °C cyclone drying oven for 2 h; the prepared impact-resistant glass fiber-reinforced polypropylene material component B (prepared by the same method as in Example 1) was dried in a 90 °C cyclone drying oven for 4 h and then injection-molded by an injection molding machine (Ningbo Haitian Plastic Machinery Group Co., Ltd., MA900) for testing.

[0091] Comparative Example 3

[0092] PP resin (Borealis, grade 10058), toughening agent (SEBS, Yueyang Petrochemical, YH-503), lubricant (erucamide, Jiangxi Zhilian Plastic Technology Co., Ltd.), compatibilizer grafted ethylene-propylene rubber (Compton Corporation, USA, 498), antioxidant (BASF China Co., Ltd., hindered phenolic antioxidant irganoxB225), PE (Shanghai Petrochemical, 200J), nucleating agent (Asahi Denka Co., Ltd., NA11), and masterbatch (Beijing Clariant Masterbatch Co., Ltd., dark gray, 1:50) were added to a high-speed mixer and stirred evenly. Subsequently, the above-mentioned mixed materials were pelletized by a twin-screw mixing extruder, and the mixing temperature was 190-230 °C, keeping the vacuum degree of the equipment vacuum system higher than -0.08 MPa; the impact-resistant glass fiber-reinforced polypropylene material component A was prepared. Its specific formulation is shown in Table 1.

[0093] The prepared impact-resistant long glass fiber-reinforced polypropylene material component A was dried in a 90 °C cyclone drying oven for 2 h and then injection-molded by an injection molding machine (Ningbo Haitian Plastic Machinery Group Co., Ltd., MA900) for testing.

[0094] Product performance test

[0095] The samples obtained from Examples 1 to 8 and Comparative Examples 1 to 3 were subjected to performance tests, and the tests included:

[0096] 1. Scratch resistance △E: The test method is Volkswagen standard PV3952, and the load is 10 N;

[0097] 2. Color difference: The test method is in accordance with ASTM D2244-21;

[0098] 3. Drop weight impact test: The test method is in accordance with ISO 6603.2:2000(E), the impact energy is 10 J, and the diameter of the hammer head is 20 mm. The samples of Examples 1 to 8 did not break in the drop weight impact test.

[0099] For the specific test results, please refer to Table 1.

[0100] Table 1 Formulation ratios and test performance data of Examples 1 to 8 and Comparative Examples 1 to 3

[0101]

[0102] 1. It can be seen from Example 1 and Comparative Example 2 that the addition of the compatibilizer reduces the scratch resistance of the material and improves the stress whitening resistance.

[0103] 2. It can be seen from the comparison between Comparative Example 3 and Example 2 that the addition of glass fiber reduces the scratch resistance of the material and improves the stress whitening resistance. The addition of glass fiber restricts the plastic deformation of the polypropylene matrix, and it is not easy to yield under force and cause molecular chain fracture and slip, thereby improving the stress whitening resistance.

[0104] 3. It can be known from the comparison between Example 2 and Example 5 that the color of the product has a decisive influence on the stress whitening resistance and scratch resistance. The performance can only be compared under the same color.

[0105] 4. It can be seen from Examples 4, 8, 6, and 7 that as the glass fiber content increases, the scratch resistance becomes worse, while the stress whitening resistance becomes better. The increase in glass fiber content increases the restriction on the plastic deformation of the polypropylene matrix, and it is not easy to yield under force and cause molecular chain fracture and slip, thereby improving the stress whitening resistance.

[0106] 5. It can be seen from the comparison between Comparative Example 1 and other examples that our means of improving the stress whitening performance is effective.

[0107] 6. It can be seen from the comparison between Example 2 and Example 8 that erucamide is superior to polypropylene scratch-resistant masterbatch in improving scratch resistance. However, erucamide is easy to migrate outwards and has a high VOC, which is not applicable in some occasions, and the lubricant can be selected according to actual needs.

[0108] As can be seen from the above, the impact-resistant glass fiber-reinforced polypropylene material of the present invention has excellent processing performance, impact resistance, stress whitening resistance, and scratch resistance, and has good comprehensive performance. It can be applied to industries such as automotive and household appliance casings.

Claims

1. An impact-resistant glass fiber-reinforced polypropylene material, the main materials of which comprise the following components: polypropylene resin, long glass fiber-reinforced polypropylene, toughening agent, compatibilizer, polyethylene; Based on the total weight of the main materials being 100 parts by weight, the dosage of each component is as follows:

2. The impact-resistant glass fiber-reinforced polypropylene material according to claim 1, characterized in that: the toughening agent is selected from SEBS.

3. The impact-resistant glass fiber-reinforced polypropylene material according to claim 1, characterized in that: the compatibilizer is selected from one or two of grafted POE, grafted ethylene-propylene rubber, and grafted PE.

4. The impact-resistant glass fiber-reinforced polypropylene material according to claim 1, characterized in that: the polyethylene is selected from at least one of HDPE, LDPE, and LLDPE; and / or, the melt index of the polyethylene is 0.5 - 10 g / 10 min (under the conditions of 190 °C and a load of 2.16 kg).

5. The impact-resistant glass fiber-reinforced polypropylene material according to claim 1, characterized in that: the polypropylene resin is a homopolymer or copolymer polypropylene with a melt index of 3 - 50 g / 10 min (under the conditions of 230 °C and a load of 2.16 kg).

6. The impact-resistant glass fiber-reinforced polypropylene material according to claim 1, wherein It further comprises a nucleating agent; the nucleating agent is an α-type nucleating agent; Preferably, based on the dosage of the main materials being 100 parts by weight, the dosage of the nucleating agent is 0.02 - 1.5 parts by weight, preferably 0.05 - 1 part by weight.

7. The impact-resistant glass fiber-reinforced polypropylene material according to claim 1, characterized in that It further comprises a lubricant; the lubricant is selected from at least one of lubricant 1 and lubricant 2; the lubricant 1 is erucamide; the lubricant 2 is a masterbatch for scratch-resistant polypropylene; the masterbatch for scratch-resistant polypropylene contains the following components in blend; polyolefin resin, lubricant 3; wherein based on 100 parts by weight of the polyolefin resin, the dosage of lubricant 3 is 10 - 70 parts by weight; the polyolefin resin is selected from a composition of polyethylene for masterbatch and / or polypropylene for masterbatch, and grafted polyethylene for masterbatch; the lubricant 3 includes a main lubricant and an auxiliary lubricant; the main lubricant is silicone powder, and the auxiliary lubricants are methyl silicone oil and polypropylene wax; the compounding ratio of the silicone powder, methyl silicone oil, and polypropylene wax is 100:(3 - 5):(5 - 7) by weight; Preferably, when the lubricant is erucamide, the dosage of polyethylene in the main materials is not 0; Preferably, based on the dosage of the main materials being 100 parts by weight, the dosage of the lubricant 1 is 0.4 - 1.2 parts by weight, preferably 0.5 - 1.0 part by weight; Preferably, based on the dosage of the main materials being 100 parts by weight, the dosage of the lubricant 2 is 1 - 8 parts by weight, preferably 3 - 6 parts by weight.

8. The impact-resistant glass fiber-reinforced polypropylene material according to claim 1, characterized in that: the long glass fiber-reinforced polypropylene is made of the following components by weight: 100 parts of impregnating polypropylene; 3 - 15 parts of compatibilizer composition; preferably 3 - 10 parts; 20 - 60 parts of glass fiber; preferably 30 - 50 parts; 3 - 25 parts of surface modifier; preferably 5 - 10 parts; The polypropylene for impregnation has a melt flow rate of 40 to 150 g / 10 min, preferably 100 to 150 g / 10 min, under the conditions of 230 °C and a load of 2.16 kg; The compatibilizer composition comprises maleic anhydride grafted polypropylene and bisphenol A diglycidyl ether; the weight ratio of maleic anhydride grafted polypropylene to bisphenol A diglycidyl ether is 1:2 to 5:1; The glass fiber is an alkali-free high-strength continuous glass fiber with a strength > 2300 MPa, a diameter of 10 to 24 μm, and a linear density of 1200 to 4800 TEX; The surface modifier is a polypropylene with an ultra-high melt index; preferably, the polypropylene with an ultra-high melt index has a melt flow rate of 150 to 10000 g / 10 min, preferably 400 to 3800 g / 10 min, under the conditions of 230 °C and a load of 2.16 kg.

9. The preparation method of the impact-resistant glass fiber reinforced polypropylene material according to any one of claims 1 to 8, characterized in that It includes the following steps: The components including the polypropylene resin, toughening agent, compatibilizer, optional nucleating agent, optional lubricant, and optional polyethylene are melt-blended in the stated amounts to obtain a modified polypropylene material, and the modified polypropylene material and the long glass fiber reinforced polypropylene are processed and formed to obtain the impact-resistant long glass fiber reinforced polypropylene material; the device used for processing and forming is preferably an injection molding machine.

10. Use of the impact-resistant glass fiber reinforced polypropylene material according to any one of claims 1 to 8 or the impact-resistant glass fiber reinforced polypropylene material prepared by the preparation method according to claim 9, preferably in the fields of automobiles and household appliances.

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