High-performance PC / PP modified material

Abstract

The invention discloses a high-performance PC / PP modified material which is prepared from the following components in parts by weight: 40-70 parts of PC, 5-15 parts of siloxane PC, 20-40 parts of PP, 3-8 parts of a toughening agent, 2-6 parts of a compatilizer, 0.3-1 part of an antioxidant and 0.5-2 parts of an ultraviolet light absorber. Melt blending is performed at 230-280 DEG C through a twin-screw extrusion process, so that the problem of poor compatibility of PC and PP is solved. The notched impact strength of the obtained material at-40 DEG C reaches 80-120 J / m, the tensile strength retention rate after damp-heat aging is larger than 90%, and the material has excellent mechanical properties, low temperature resistance and aging resistance and is suitable for automobile parts and outdoor electronic equipment shells.

Description

Technical Field

[0001] The present invention belongs to the technical field of polymer material modification, and specifically relates to a high-performance PC / PP modified material. Background Art

[0002] Polycarbonate, English name Polycarbonate, abbreviated as PC. PC is an amorphous, odorless, non-toxic, highly transparent colorless or slightly yellow thermoplastic engineering plastic, with excellent physical and mechanical properties, especially excellent impact resistance, high tensile strength, flexural strength, and compressive strength; small creep, stable dimensions; light-stable. The disadvantages are poor fatigue resistance, easy stress cracking, poor solvent resistance, and poor wear resistance. To improve the defects of PC, PC is generally alloyed or blended with different polymers to improve material properties, utilize the advantages of two or more material properties, and reduce costs.

[0003] PP material, also known as polypropylene, is a colorless, odorless, non-toxic, semi-transparent, and excellent-performance thermoplastic synthetic resin, belonging to thermoplastic lightweight general plastics, and is one of the lightest varieties of plastics. PP material has very good mechanical properties. Except for impact resistance, other mechanical properties are better than those of polyethylene, and the molding and processing properties are very good. However, the products of PP material have poor cold resistance and low low-temperature impact strength. During the use of its products, due to the action of light, heat, and oxygen, they are prone to aging, have very poor coloring properties, and are also prone to combustion.

[0004] In view of the characteristics of PC and PP materials, combining PP and PC can make up for each other's strengths and weaknesses and improve the comprehensive properties of the materials. PP can improve the impact resistance and heat resistance of PC, while PC can improve the transparency and hardness of PP, etc., making the material have better comprehensive properties and meeting specific requirements. However, the compatibility of PC and PP is not ideal, and PP material is easily decomposed by ultraviolet rays. There are still limitations in some aspects of the mixed material, such as limited low-temperature resistance, which restricts the application of PC and PP blend materials. Summary of the Invention

[0005] The present invention aims to avoid the deficiencies of the prior art and applications, and provides a high-performance PC / PP modified material.

[0006] To achieve the above object, the technical solution adopted by the present invention is: a high-performance PC / PP modified material, characterized in that it is prepared from the following components in parts by weight: 40 - 70 parts of PC, 5 - 15 parts of silicone PC, 20 - 40 parts of PP, 3 - 8 parts of toughening agent, 2 - 6 parts of compatibilizer, 0.3 - 1 part of antioxidant, 0.5 - 2 parts of ultraviolet absorber; The specific preparation method is as follows: Feed polypropylene into the main feeding port of a twin-screw extruder, and add the remaining components through the side feeding port after thorough premixing. Then, melt and extrude into pellets at 230 - 280 °C and a screw rotation speed of 300 - 500 rpm.

[0007] Further, the PC is bisphenol A polycarbonate with a melt flow rate of 10 - 25 g / 10 min (at 300 °C / 1.2 kg).

[0008] Further, the silicone PC is a polysiloxane - polycarbonate random copolymer, where the polysiloxane block accounts for 18 - 22% of the total weight of the copolymer, and the melt flow rate is 10 - 15 g / 10 min (at 300 °C / 1.2 kg).

[0009] Further, the PP is homopolypropylene with a melt flow rate of 5 - 20 g / 10 min (at 230 °C / 2.16 kg).

[0010] Further, the toughening agent is an ethylene - butyl acrylate - glycidyl methacrylate terpolymer (E - MA - GMA), where the content of glycidyl methacrylate is 3 - 5 wt%.

[0011] Further, the compatibilizer is maleic anhydride grafted polypropylene (PP - g - MAH) with a grafting rate of 1.5 - 2.5%.

[0012] Further, the antioxidant is a mixture of antioxidant 1010 and antioxidant 168; specifically, pentaerythritol tetra[β-(3,5 - di - tert - butyl - 4 - hydroxyphenyl)propionate] and tris(2,4 - di - tert - butylphenyl) phosphite are compounded at a mass ratio of 1:1.

[0013] Further, the ultraviolet absorber is UV - 327, that is, 2-(2 - benzotriazol - 2 - yl)-4,6 - di - tert - amylphenol.

[0014] The beneficial effects of the present invention are as follows: Introducing silicone PC inhibits the low - temperature brittle fracture of the blended material; adopting the two - step feeding method, PP is separately melted and plasticized and then mixed with the premixed other components in the middle section of the extruder to avoid the high - temperature degradation of PP; optimizing the anti - aging system, the compounding of antioxidant 1010 / 168 inhibits thermal - oxidative aging, and the Si - O bond of UV - 327 and silicone PC synergistically improves the ultraviolet shielding efficiency. Through the twin - screw extrusion process, melt blending is carried out at 230 - 280 °C, solving the problem of poor compatibility between PC and PP. The obtained material has a notched impact strength of 80 - 120 J / m at - 40 °C, and has excellent mechanical properties, low - temperature resistance and anti - aging properties, and is suitable for automotive parts and outdoor electronic device housings. Specific embodiments

[0015] The principles and features of the present invention are described below. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention. Example 1 A high-performance PC / PP modified material is prepared as follows:

[0016] PC and silicone PC are dried at 100 °C for 4 hours, and PP is dried at 80 °C for 2 hours for standby; PP is separately added to the main feed bin; PC, silicone PC, toughening agent, compatibilizer, antioxidant and ultraviolet absorber are mixed in a mixer at a rotation speed of 1200 rpm for 3 minutes and then added from the side feed bin. The proportion of each component is shown in Table (1); The temperature zoning setting parameters of the screw extruder are as follows: Zone 1: 230 °C, Zone 2: 250 °C, Zone 3: 270 °C, Zone 4: 265 °C, die head: 260 °C; the screw rotation speed is 400 rpm, the side feed bin port is located in Zone 5, and the vacuum degree is -0.08 MPa; after the melt is extruded, it is cooled and pelletized by water, and injection molded in an injection molding machine into standard test specimens for performance testing. The results are shown in Table (2).

[0017] Table (1) Proportion of each component (unit: parts by mass)

[0018] Table (2) Performance test results

[0019] Example 2

[0020] A high-performance PC / PP modified material is prepared in the same way as in Example 1. The proportion of each component is shown in Table (1), and the performance test is shown in Table (2).

[0021] Examples 3 - 5 are the same as Example 2.

[0022] According to the disclosure and teachings of the above specification, those skilled in the art to which the present invention pertains can also make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the invention should also fall within the protection scope of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for convenience of description and do not constitute any limitation to the present invention.

Claims

1. A high-performance PC / PP modified material, characterized in that: It is prepared from the following components in parts by weight: PC 40-70 parts, siloxane PC 5-15 parts, PP 20-40 parts, toughening agent 3-8 parts, compatibilizer 2-6 parts, antioxidant 0.3-1 parts, ultraviolet absorber 0.5-2 parts; The specific preparation method is: feed PP into the main feeding port of the twin-screw extruder, and add the remaining components from the side feeding port after being fully premixed and evenly mixed, and melt extrude and granulate at 230-280°C and a screw speed of 300-500rpm.

2. A high-performance PC / PP modified material according to claim 1, characterized in that: The PC is bisphenol A polycarbonate, and the melt flow rate is 10-25 g / 10 min.

3. A high-performance PC / PP modified material according to claim 1, characterized in that: The siloxane PC is a polysiloxane-polycarbonate random copolymer, wherein the polysiloxane block accounts for 18-22% of the total weight of the copolymer, and the melt flow rate is 10-15 g / 10 min.

4. A high-performance PC / PP modified material according to claim 1, characterized in that: The PP is homopolymer polypropylene, and the melt flow rate is 5-20g / 10min.

5. A high-performance PC / PP modified material according to claim 1, characterized in that: The toughening agent is ethylene-butyl acrylate-glycidyl methacrylate terpolymer (E-MA-GMA), wherein the content of glycidyl methacrylate is 3-5wt%.

6. A high-performance PC / PP modified material according to claim 1, characterized in that: The compatibilizer is maleic anhydride grafted polypropylene (PP-g-MAH) with a grafting rate of 1.5-2.5%.

7. A high-performance PC / PP modified material according to claim 1, characterized in that: The antioxidant is a mixture of antioxidant 1010 and antioxidant 168; specifically, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate and tris(2,4-di-tert-butylphenyl) phosphite are compounded in a mass ratio of 1:

1.

8. A high performance PC / PP modified material according to claim 1, characterized in that: The ultraviolet absorber is UV-327, namely 2-(2-benzotriazole-2-yl)-4,6-di-tert-amylphenol.

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