A high-performance glass fiber reinforced polypropylene material and preparation method thereof

Abstract

The invention discloses a high-performance glass fiber reinforced polypropylene material and a preparation method thereof. The glass fiber reinforced polypropylene material is prepared by mixing 59.1 to 87.6 parts of polypropylene, 10 to 30 parts of glass fiber, 1 to 6 parts of maleic anhydride grafted polypropylene, 1 to 4 parts of random copolymerized polypropylene, 0.2 to 0.5 parts of antioxidant and 0.2 to 0.4 parts of light stabilizer according to weight parts, and then processed by a twin-screw extrusion process. On the basis of the existing glass fiber reinforced polypropylene material, a small amount of random copolymerized polypropylene is added, thereby increasing the length retention rate of glass fiber in the polypropylene base material, improving the performance of the glass fiber reinforced polypropylene material, and obtaining a high-performance glass fiber reinforced polypropylene material.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer material modification, and in particular relates to a high-performance glass fiber reinforced polypropylene material and a preparation method thereof. Background Art

[0002] Polypropylene (PP) is one of the most commonly used general-purpose plastics. Due to its excellent comprehensive properties such as light density, low water absorption, and abundant raw material sources, it is widely used in daily necessities, automobiles, home appliances and other fields.

[0003] In practical applications, some functional additives or functional components are usually added to the polypropylene system to improve the performance of polypropylene materials, such as improving the rigidity of polypropylene materials by reinforcing polypropylene resin with glass fiber. However, for glass fiber reinforced polypropylene materials, glass fiber is the main material in the material to resist external stress, and the retention rate of glass fiber length plays a vital role in the comprehensive mechanical properties of the material. Studies have shown that the longer the glass fiber retention rate, the more effectively it can prevent the diffusion of silver streaks generated when it is hit, thereby improving the toughness of the material; at the same time, the longer the glass fiber retention rate, the more obvious the glass fiber orientation in the material, and the glass fiber can effectively bear the tension and pressure on the material, so that the reinforced polypropylene material with a longer glass fiber retention rate has a higher strength.

[0004] Therefore, it is urgent to find a new method to improve the retention rate of glass fiber length in polypropylene materials to improve the performance of polypropylene materials. Summary of the invention

[0005] In view of this, the primary purpose of the present invention is to provide a high-performance glass fiber reinforced polypropylene material, based on the existing glass fiber reinforced polypropylene material, adding a small amount of random copolymer polypropylene, so as to improve the length retention rate of glass fiber in the polypropylene base material.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The first aspect of the present invention provides a high-performance glass fiber reinforced polypropylene material, which is prepared by mixing 59.1 to 87.6 parts of polypropylene, 10 to 30 parts of glass fiber, 1 to 6 parts of maleic anhydride grafted polypropylene, 1 to 4 parts of random copolymerized polypropylene, 0.2 to 0.5 parts of antioxidant and 0.2 to 0.4 parts of light stabilizer according to weight parts and processed by a twin-screw extrusion process.

[0008] In one embodiment, the polypropylene is copolymer polypropylene, homopolymer polypropylene, or a mixture of two or more thereof.

[0009] In one embodiment, the glass fiber is chopped glass fiber or curly fiber.

[0010] In one embodiment, the glass fiber has a diameter of 10 to 30 μm.

[0011] In one implementation case, the maleic anhydride is grafted onto polypropylene, and the grafting rate of maleic anhydride is 0.5-3 wt %.

[0012] In one implementation case, the random copolymer polypropylene is formed by randomly inserting ethylene molecules into the main chain of polypropylene; wherein the content of the inserted ethylene molecules is 1 wt% to 7 wt%.

[0013] In one embodiment, the antioxidant is at least one of a phenolic antioxidant, a phosphite antioxidant, and a thioester antioxidant.

[0014] In one embodiment, the light stabilizer is at least one of phenyl o-hydroxybenzoate, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, 2-(2'-hydroxy-3',5'-di-tert-phenyl)-5-chlorobenzotriazole and monobenzoic acid resorcinol ester.

[0015] A second aspect of the present invention provides a method for preparing the high-performance glass fiber reinforced polypropylene material as described above, comprising the following steps:

[0016] 59.1-87.6 parts of polypropylene, 1-6 parts of maleic anhydride grafted polypropylene, 1-4 parts of random copolymer polypropylene material, 0.2-0.5 parts of antioxidant and 0.2-0.4 parts of light stabilizer are mixed evenly according to weight ratio, and then added into the main feeding port of a twin-screw extruder. At the same time, 10-30 parts of glass fiber are fed into the glass fiber port, and melt-extruded and granulated by the twin-screw extruder to obtain a high-performance glass fiber modified polypropylene material.

[0017] In one implementation case, the screw speed of the twin-screw extruder is 300-600 rpm, and the temperature in the barrel is 200-250°C.

[0018] Beneficial effects of the present invention:

[0019] The present invention is based on the existing glass fiber reinforced polypropylene material, and a small amount of random copolymerized polypropylene is added to the formula, so as to improve the length retention rate of glass fiber in the base material and achieve the requirements of overall rigidity and toughness of glass fiber reinforced polypropylene material. Since the melting point of random copolymerized polypropylene is slightly lower than that of polypropylene material by about 20°C, that is, usually between 135°C-150°C, therefore, during the processing, under the shearing action of the twin screws, at the front end of the screw, since the pellets are just in the melting stage and have not yet completely melted, the polypropylene is still in the stage where the molecular chain cannot move freely, but since there is a part of random copolymerized polypropylene in the system, the melting point of this part is relatively low, which can reduce the damage of the screw shear force to the matrix resin to a certain extent, so as to reduce the degree of damage to the glass fiber; and at the rear end of the screw, due to the presence of random copolymerized polypropylene in the system, there is a viscosity gradient in the system, so that the system is easier to flow in the direction consistent with the rotation of the screw, and the glass fiber is prevented from being entangled and broken due to the unstable state of mixing flow. Therefore, the glass fiber reinforced polypropylene material in the present invention can improve the length retention rate of glass fiber in the base material under the same process conditions. DETAILED DESCRIPTION

[0020] Embodiments of the present invention are described in detail below, and the embodiments described below are exemplary, are only used to explain the present invention, and are not to be construed as limiting the present invention. Unless otherwise defined, all technical and scientific terms used herein are identical with the meanings generally understood by those skilled in the art belonging to the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. In addition, if not otherwise specified, the method for not specifically recording conditions or steps is a conventional method, and the reagents and materials adopted can all be obtained from commercial sources.

[0021] Example 1

[0022] This embodiment provides a high-performance glass fiber reinforced polypropylene material, and its raw material composition and dosage are as follows:

[0023]

[0024] The preparation method of the high-performance glass fiber reinforced polypropylene material is as follows:

[0025] 80.4 parts of polypropylene, 2 parts of maleic anhydride grafted polypropylene, 2 parts of random copolymerized polypropylene, 0.1 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.1 parts of light stabilizer phenyl o-hydroxybenzoate and 0.2 parts of light stabilizer 2-(2'-hydroxy-5'-methylphenyl)benzotriazole are fully mixed in a high-pressure mixer and fed from the main material port of a twin-screw extruder. 15 parts of glass fiber are fed from the glass fiber port. After melt extrusion and granulation, a high-performance glass fiber reinforced polypropylene material is obtained. The rotation speed of the twin-screw extruder is 400 rpm, and the temperature of the twin-screw extruder from the feeding section to the die head is 190° C., 190° C., 200° C., 210° C., 210° C., 210° C., 210° C., 210° C., 210° C., 210° C., 210° C., 210° C.

[0026] Example 2

[0027] This embodiment provides a high-performance glass fiber reinforced polypropylene material, and its raw material composition and dosage are as follows:

[0028]

[0029]

[0030] The preparation method of the high-performance glass fiber reinforced polypropylene material is as follows:

[0031] According to weight parts, 72.3 parts of polypropylene, 4 parts of maleic anhydride grafted polypropylene, 3 parts of random copolymerized polypropylene, 0.2 parts of antioxidant 1010, 0.1 parts of antioxidant 168, 0.1 parts of antioxidant DSTDP, and 0.3 parts of light stabilizer 2,4-dihydroxybenzophenone are fully mixed in a high mixer and fed from the main material port of a twin-screw extruder, 20 parts of glass fiber are fed from the glass fiber port, and granulated by melt extrusion to obtain a high-performance glass fiber reinforced polypropylene material, wherein the rotation speed of the twin-screw extruder is 500 rpm, and the temperature of the twin-screw extruder from the feeding section to the die head is 200°C, 200°C, 210°C, 210°C, 220°C, 220°C, 220°C, 210°C, and 210°C, respectively.

[0032] Example 3

[0033] This embodiment provides a high-performance glass fiber reinforced polypropylene material, and its raw material composition and dosage are as follows:

[0034]

[0035] The preparation method of the high-performance glass fiber reinforced polypropylene material is as follows:

[0036] According to weight parts, 72.3 parts of polypropylene, 4 parts of maleic anhydride grafted polypropylene, 3 parts of random copolymerized polypropylene, 0.2 parts of antioxidant 1010, 0.1 parts of antioxidant 168, 0.1 parts of antioxidant DSTDP, and 0.3 parts of light stabilizer 2,4-dihydroxybenzophenone are fully mixed in a high mixer and fed from the main material port of a twin-screw extruder, 25 parts of glass fiber are fed from the glass fiber port, and granulated by melt extrusion to obtain a high-performance glass fiber reinforced polypropylene material, wherein the rotation speed of the twin-screw extruder is 500 rpm, and the temperature of the twin-screw extruder from the feeding section to the die head is 210°C, 210°C, 210°C, 220°C, 220°C, 220°C, 230°C, 230°C, 220°C, and 210°C, respectively.

[0037] Example 4

[0038] This embodiment provides a high-performance glass fiber reinforced polypropylene material, and its raw material composition and dosage are as follows:

[0039]

[0040] The preparation method of the high-performance glass fiber reinforced polypropylene material is as follows:

[0041] 87.6 parts of polypropylene, 1 part of maleic anhydride grafted polypropylene, 1 part of random copolymer polypropylene, 0.1 part of antioxidant 1010, 0.1 part of antioxidant 168, and 0.2 part of light stabilizer 2-hydroxy-4-n-octyloxybenzophenone were fully mixed in a high mixer according to weight parts, and then fed from the main material port of a twin-screw extruder, 10 parts of glass fiber were fed from the glass fiber port, and granulated by melt extrusion to obtain a high-performance glass fiber reinforced polypropylene material, wherein the rotation speed of the twin-screw extruder is 350 rpm, and the temperature of the twin-screw extruder from the feeding section to the die head is 180°C, 180°C, 190°C, 190°C, 200°C, 200°C, 210°C, 210°C, 210°C, 210°C, and 210°C, respectively.

[0042] Example 5

[0043] This embodiment provides a high-performance glass fiber reinforced polypropylene material, and its raw material composition and dosage are as follows:

[0044]

[0045] The preparation method of the high-performance glass fiber reinforced polypropylene material is as follows:

[0046] According to weight parts, 60.1 parts of polypropylene, 5 parts of maleic anhydride grafted polypropylene, 4 parts of random copolymerized polypropylene, 0.2 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.1 parts of antioxidant DSTDP, 0.2 parts of light stabilizer 2-hydroxy-4-n-octyloxybenzophenone and 0.1 parts of light stabilizer 2-(2'-hydroxy-3',5'-di-tert-phenyl)-5-chlorobenzotriazole and 0.1 parts of monobenzoic acid resorcinol ester were added. After being fully mixed in the high-speed mixer, the mixture is fed from the main material port of the twin-screw extruder, and 30 parts of glass fibers are fed from the glass fiber port. The mixture is melt-extruded and granulated to obtain a high-performance glass fiber reinforced polypropylene material. The rotation speed of the twin-screw extruder is 350 rpm, and the temperature of the twin-screw extruder from the feeding section to the die head is 200°C, 200°C, 210°C, 210°C, 230°C, 240°C, 220°C, 220°C, 210°C, and 210°C, respectively.

[0047] Comparative Example 1

[0048] This comparative example provides another high-performance glass fiber reinforced polypropylene material, and its raw material composition and dosage are as follows:

[0049]

[0050] The preparation method of the high-performance glass fiber reinforced polypropylene material is as follows:

[0051] 82.4 parts of polypropylene, 2 parts of maleic anhydride grafted polypropylene, 0.1 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.1 parts of light stabilizer phenyl o-hydroxybenzoate and 0.2 parts of 2-(2-hydroxy-5-methylphenyl)benzotriazole are fully mixed in a high-pressure mixer and fed from the main material port of a twin-screw extruder. 15 parts of glass fiber are fed from the glass fiber port. After melt extrusion and granulation, a high-performance glass fiber reinforced polypropylene material is obtained, wherein the rotation speed of the twin-screw extruder is 400 rpm, and the temperature of the twin-screw extruder from the feeding section to the die head is 190° C., 190° C., 200° C., 210° C., 210° C., 210° C., 210° C., 210° C., 210° C., 210° C., 210° C., 210° C., 210° C.

[0052] Comparative Example 2

[0053] This comparative example provides another high-performance glass fiber reinforced polypropylene material, and its raw material composition and dosage are as follows:

[0054]

[0055]

[0056] The preparation method of the high-performance glass fiber reinforced polypropylene material is as follows:

[0057] According to weight parts, 75.3 parts of polypropylene, 4 parts of maleic anhydride grafted polypropylene, 0.2 parts of antioxidant 1010, 0.1 parts of antioxidant 168, 0.1 parts of antioxidant DSTDP, and 0.3 parts of light stabilizer 2,4-dihydroxybenzophenone are fully mixed in a high mixer and fed from the main material port of a twin-screw extruder, 20 parts of glass fiber are fed from the glass fiber port, and granulated by melt extrusion to obtain a high-performance glass fiber reinforced polypropylene material, wherein the rotation speed of the twin-screw extruder is 500 rpm, and the temperature of the twin-screw extruder from the feeding section to the die head is 200°C, 200°C, 210°C, 210°C, 220°C, 220°C, 220°C, 210°C, and 210°C, respectively.

[0058] Performance Testing

[0059] The glass fiber reinforced polypropylene materials prepared in the examples and comparative examples were injection molded into specimens, and the relevant properties were tested according to the standards:

[0060] (1) Tensile strength: tested in accordance with ISO527-2 "Test method for tensile properties of plastics", the specimen size is 150×10×4 mm, and the tensile speed is 50 mm / min;

[0061] (2) Flexural strength: tested in accordance with ISO178-2010 “Determination of flexural properties of plastics”, the bending specimen size is 80×10×4 mm, and the test speed is 2 mm / min;

[0062] (3) The fiber length test method is to take the ash residue of the modified polypropylene burned in the muffle furnace. Specifically, put the glass fiber reinforced polypropylene material into the muffle furnace and burn it at a temperature of 750℃±50℃ for 5-10min. Collect the residual material after burning, which is the glass fiber. Spread the glass fiber on a glass dish and use a fiber length distribution measuring instrument to test the length and distribution of each group of glass fibers. The results are shown in the following table:

[0063] Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Tensile strength(MPa) 82 61 67 52 112 75 49 Bending strength(MPa) 114 89 92 86 143 91 75 Fiber length (μm) 694 834 812 769 743 312 354

[0064] It can be seen that the glass fiber length retention rate of the glass fiber reinforced polypropylene material prepared by the present invention is as high as 600-900 μm, and thus, it has higher mechanical properties than traditional glass fiber reinforced polypropylene materials.

[0065] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0066] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A high-performance glass fiber reinforced polypropylene material, characterized in that: The invention is prepared by mixing 59.1 to 87.6 parts of polypropylene, 10 to 30 parts of glass fiber, 1 to 6 parts of maleic anhydride grafted polypropylene, 1 to 4 parts of random copolymerized polypropylene, 0.2 to 0.5 parts of antioxidant and 0.2 to 0.4 parts of light stabilizer according to weight parts, and then processed by twin-screw extrusion process.

2. The high performance glass fiber reinforced polypropylene material according to claim 1, characterized in that: The polypropylene is copolymer polypropylene, homopolymer polypropylene or a mixture of two or more thereof.

3. The high performance glass fiber reinforced polypropylene material according to claim 1, characterized in that: The glass fibers are chopped glass fibers or curly fibers.

4. The high performance glass fiber reinforced polypropylene material according to claim 3, characterized in that: The glass fiber has a diameter of 10 to 30 μm.

5. The high performance glass fiber reinforced polypropylene material according to claim 1, characterized in that: The maleic anhydride grafted polypropylene has a grafting rate of maleic anhydride of 0.5-3wt%.

6. The high performance glass fiber reinforced polypropylene material according to claim 1, characterized in that: The random copolymer polypropylene is obtained by randomly inserting ethylene molecules into the main chain of polypropylene, wherein the content of the inserted ethylene molecules is 1wt% to 7wt%.

7. The high performance glass fiber reinforced polypropylene material according to claim 1, characterized in that: The antioxidant is at least one of a phenolic antioxidant, a phosphite antioxidant, and a thioester antioxidant.

8. The high performance glass fiber reinforced polypropylene material according to claim 1, characterized in that: The light stabilizer is at least one of phenyl o-hydroxybenzoate, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, 2-(2'-hydroxy-3',5'-di-tert-phenyl)-5-chlorobenzotriazole and monobenzoic acid resorcinol ester.

9. A method for preparing a high-performance glass fiber reinforced polypropylene material according to any one of claims 1 to 8, characterized in that: The following steps are involved: 59.1-87.6 parts of polypropylene, 1-6 parts of maleic anhydride grafted polypropylene, 1-4 parts of random copolymer polypropylene material, 0.2-0.5 parts of antioxidant and 0.2-0.4 parts of light stabilizer are mixed evenly according to weight ratio, and then added into the main feeding port of a twin-screw extruder. At the same time, 10-30 parts of glass fiber are fed into the glass fiber port, and melt-extruded and granulated by the twin-screw extruder to obtain a high-performance glass fiber modified polypropylene material.

10. The preparation method according to claim 9, characterized in that: The screw speed of the twin-screw extruder is 300-600 rpm, and the temperature in the barrel is 200-250°C.

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