Bio-based degradable continuous fiber reinforced polypropylene composite material and preparation method thereof

Abstract

The invention discloses a bio-based degradable continuous fiber reinforced polypropylene composite material and a preparation method thereof, and belongs to the technical field of high polymer material modification. The bio-based degradable continuous fiber reinforced polypropylene composite material is prepared from the following raw materials in parts by mass: 50 to 70 parts of polypropylene resin, 20 to 40 parts of bio-based degradable fiber, 5 to 10 parts of compatilizer, 1 to 3 parts of coupling agent and 0.5 to 2 parts of auxiliary agent. The bio-based degradable fiber is subjected to pretreatment and surface modification, and the compatilizer is added, so that the compatibility and interface bonding force of the bio-based degradable fiber and a polypropylene matrix are improved, the composite material has excellent mechanical properties and environmental protection performance, and the preparation method is simple and suitable for industrial production.

Description

Technical Field

[0001] This invention belongs to the field of polymer material modification technology, specifically relating to a bio-based biodegradable continuous fiber reinforced polypropylene composite material and its preparation method. Background Technology

[0002] With increasing environmental awareness and the pursuit of sustainable development, the development of environmentally friendly composite materials with excellent overall performance has become a research hotspot in the field of materials science. Polypropylene (PP), a common thermoplastic resin, is widely used in various fields due to its advantages such as light weight, corrosion resistance, and ease of processing. However, pure polypropylene materials have relatively low mechanical properties, such as insufficient tensile strength and flexural strength, which limits its application in some applications with high mechanical performance requirements. To improve the mechanical properties of polypropylene, fiber reinforcement is usually adopted. Traditional fiber reinforcement materials are mostly inorganic fibers such as glass fiber and carbon fiber. Although they can significantly improve the mechanical properties of polypropylene, these inorganic fibers have problems such as high energy consumption and environmental unfriendliness in the production process, poor compatibility with the polypropylene matrix, and difficulty in degradation after disposal, which can cause environmental pollution. In addition, some existing bio-based biodegradable fiber-reinforced polypropylene composites still have certain defects in terms of interfacial bonding between fibers and matrix and weather resistance of composite materials, resulting in the need for further improvement in the overall performance of composite materials.

[0003] Therefore, developing a bio-based biodegradable continuous fiber reinforced polypropylene composite material with good environmental performance, excellent mechanical properties, and strong interfacial bonding is of great practical significance. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a bio-based biodegradable continuous fiber reinforced polypropylene composite material and its preparation method, thereby solving the problems in the prior art.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A bio-based biodegradable continuous fiber reinforced polypropylene composite material, comprising the following raw materials in parts by weight:

[0007]

[0008] Furthermore, the bio-based biodegradable fiber includes: bio-based polymer fiber, cellulose fiber, chitin fiber, polylactic acid fiber, or polycaprolactone fiber.

[0009] Furthermore, the compatibilizer is maleic anhydride-grafted polypropylene.

[0010] Furthermore, the coupling agent is a silane coupling agent.

[0011] Furthermore, the additives include antioxidants and light stabilizers, wherein the antioxidant is a hindered phenolic antioxidant and the light stabilizer is a hindered amine light stabilizer.

[0012] The above-mentioned method for preparing a bio-based biodegradable continuous fiber reinforced polypropylene composite material includes the following steps:

[0013] S1. After cleaning and drying, the bio-based biodegradable fiber is soaked in sodium hydroxide solution, then rinsed with deionized water until neutral, and dried again to obtain the pretreated bio-based biodegradable fiber.

[0014] S2, the pretreated bio-based biodegradable fiber is mixed with a coupling agent, an organic solvent is added to react, and then filtered and dried to obtain surface-modified bio-based biodegradable fiber;

[0015] S3, mix polypropylene resin, compatibilizer and additives to obtain a mixture;

[0016] S4 involves adding the mixture to a twin-screw extruder for melt blending, with surface-modified biodegradable fibers passing through the die, followed by melt impregnation, granulation, cooling, and drying to obtain a polypropylene composite material.

[0017] Furthermore, the concentration of the sodium hydroxide solution is 5-10 wt%.

[0018] Furthermore, the reaction temperature for mixing bio-based biodegradable fibers with coupling agents is 50-80℃.

[0019] Furthermore, the barrel temperature of the twin-screw extruder is 160℃ in zone 1, 210℃ in zone 2, 220℃ in zone 3, 230℃ in zone 4, 240℃ in zone 5, 250℃ in zone 6, the die temperature is 250℃, the screw speed is 260r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

[0020] The above-mentioned bio-based biodegradable continuous fiber reinforced polypropylene composite material is used as a raw material in the preparation of automotive interior parts.

[0021] The beneficial effects of this invention are:

[0022] 1. This invention uses bio-based biodegradable fibers as reinforcing materials. Bio-based biodegradable fibers are renewable and degradable, which greatly improves the environmental performance of composite materials and meets the requirements of sustainable development.

[0023] 2. By pretreating and surface modifying bio-based biodegradable fibers, since bio-based biodegradable fibers usually contain ester groups, alkaline solutions are used to promote the degradation of ester bonds on the fiber surface to generate a large number of hydroxyl groups, which is conducive to the grafting modification of materials by increasing silane groups. The reaction mechanism is: [R-Si(OH)3+-OH(material surface)→R-Si-O-(material surface)+2H2O]. Therefore, the compatibility and interfacial bonding force between bio-based biodegradable fibers and polypropylene matrix are improved, thereby significantly improving the mechanical properties of composite materials, such as tensile strength, flexural strength and impact strength.

[0024] 3. The addition of maleic anhydride grafted polypropylene as a compatibilizer further improves the interfacial compatibility between the bio-based biodegradable fiber and the polypropylene matrix, resulting in a more superior overall performance of the composite material.

[0025] 4. The addition of additives improves the antioxidant properties and weather resistance of the composite material, and extends its service life.

[0026] 5. The preparation method of the present invention is simple in process, easy to operate, and suitable for large-scale industrial production. Detailed Implementation

[0027] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] A bio-based biodegradable continuous fiber reinforced polypropylene composite material, comprising the following raw materials in parts by weight:

[0029]

[0030] Bio-based biodegradable fibers include: bio-based polymer fibers (such as flax fibers), cellulose fibers (such as rayon), chitin fibers, polylactic acid (PLA) fibers, and polycaprolactone (PCL) fibers.

[0031] The compatibilizer is maleic anhydride-grafted polypropylene. The coupling agent is silane coupling agent KH-550.

[0032] The additives include antioxidants and light stabilizers, wherein the antioxidant is hindered phenolic antioxidant 1010 and the light stabilizer is hindered amine light stabilizer 770.

[0033] The preparation method of this polypropylene composite material includes the following steps:

[0034] 1) After cleaning and drying the bio-based biodegradable fiber, immerse it in a 5-10 wt% sodium hydroxide solution for 1-2 hours, then remove it, rinse it with deionized water until neutral, and dry it again to obtain the pretreated bio-based biodegradable fiber.

[0035] 2) Surface modification: The pretreated bio-based biodegradable fiber is mixed with a coupling agent, an appropriate amount of organic solvent is added, and the mixture is reacted at 50-80℃ for 2-4 hours. Then it is filtered and dried to obtain surface-modified bio-based biodegradable fiber.

[0036] 3) Mixing: Add polypropylene resin, compatibilizer, and additives to a high-speed mixer and mix at 80-100℃ for 10-15 minutes to obtain a mixture.

[0037] 4) Melt blending: The mixture is added to a twin-screw extruder for melt blending. Bio-based biodegradable continuous fibers pass through the die, are melt-impregnated, granulated, cooled, and dried to obtain a bio-based biodegradable continuous fiber reinforced polypropylene composite material.

[0038] The parallel twin-screw extruder has the following barrel temperatures: zone 1 160℃, zone 2 210℃, zone 3 220℃, zone 4 230℃, zone 5 240℃, zone 6 250℃, die temperature 250℃, screw speed 260 r / min, melt pressure 1.0 MPa, and vacuum degree -0.06 MPa.

[0039] The technical solution of the present invention will be described in detail below through the following embodiments (all parts in the embodiments are parts by weight); the specific information of the raw materials used in the following embodiments 1-3 is as follows:

[0040] Polypropylene resin, grade K7100, melt index 100g / 10min, manufacturer: Yanshan Petrochemical.

[0041] Bio-based biodegradable fiber, also known as bio-based polymer fiber (flax fiber), manufacturer: Jiangsu Sanlian New Material Co., Ltd.

[0042] The preferred compatibilizer is maleic anhydride-grafted polypropylene, grade: Saudi Basel 350K, grafting rate 0.7-0.9%, manufacturer: Dongguan Shenghao Plastic Raw Materials Co., Ltd.

[0043] The additives are antioxidants (hindered phenolic antioxidant 1010) and light stabilizers (hindered amine light stabilizers 770), both of which are conventional commercially available materials.

[0044] Example 1

[0045] S1, after washing and drying 20 parts of bio-based biodegradable fiber (linen fiber), immerse it in a solution with a concentration of 5... wtSoak the fiber in a % sodium hydroxide solution for 1 hour, then rinse it with deionized water until neutral, and dry it again to obtain the pretreated bio-based biodegradable fiber; then mix the pretreated bio-based biodegradable fiber with 1 part of silane coupling agent KH-550, add ethanol and react at 50°C for 2 hours, then filter and dry to obtain the surface-modified bio-based biodegradable fiber.

[0046] S2, weigh 50 parts of polypropylene resin, 5 parts of maleic anhydride grafted polypropylene, 0.5 parts of hindered phenolic antioxidant 1010 and 0.5 parts of hindered amine light stabilizer 770 according to the weight, add them to a high-speed mixer, mix at 80°C for 10 minutes to obtain a mixture.

[0047] S3, the mixture is added to a twin-screw extruder for melt blending, and the surface-modified bio-based biodegradable fibers pass through the die. After melt impregnation, granulation, cooling and drying, a bio-based biodegradable continuous fiber reinforced polypropylene composite material is obtained. The barrel temperature of the twin-screw extruder is 160℃ in zone 1, 210℃ in zone 2, 220℃ in zone 3, 230℃ in zone 4, 240℃ in zone 5, 250℃ in zone 6, the die temperature is 250℃, the screw speed is 260r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

[0048] Example 2

[0049] S1, after washing and drying 30 parts of bio-based biodegradable fiber (flax fiber), immerse it in a solution with a concentration of 5... wt Soak the fiber in a % sodium hydroxide solution for 1 hour, then rinse it with deionized water until neutral, and dry it again to obtain the pretreated bio-based biodegradable fiber; then mix the pretreated bio-based biodegradable fiber with 3 parts of silane coupling agent KH-550, add ethanol and react at 50°C for 2 hours, then filter and dry to obtain the surface-modified bio-based biodegradable fiber.

[0050] S2, weigh 70 parts of polypropylene resin, 10 parts of maleic anhydride-grafted polypropylene, 1 part of hindered phenolic antioxidant 1010, and 1 part of hindered amine light stabilizer 770 according to the weight, add them to a high-speed mixer, and mix at 80°C for 10 minutes to obtain a mixture.

[0051] S3, the mixture is added to a twin-screw extruder for melt blending, and the surface-modified bio-based biodegradable fibers pass through the die. After melt impregnation, granulation, cooling and drying, a bio-based biodegradable continuous fiber reinforced polypropylene composite material is obtained. The barrel temperature of the twin-screw extruder is 160℃ in zone 1, 210℃ in zone 2, 220℃ in zone 3, 230℃ in zone 4, 240℃ in zone 5, 250℃ in zone 6, the die temperature is 250℃, the screw speed is 260r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

[0052] Example 3

[0053] S1, after washing and drying 40 parts of bio-based biodegradable fiber (flax fiber), immerse it in a solution with a concentration of 5... wt Soak the fiber in a % sodium hydroxide solution for 1 hour, then rinse it with deionized water until neutral, and dry it again to obtain the pretreated bio-based biodegradable fiber; then mix the pretreated bio-based biodegradable fiber with 2 parts of silane coupling agent KH-550, add ethanol and react at 50°C for 2 hours, then filter and dry to obtain the surface-modified bio-based biodegradable fiber.

[0054] S2, weigh 60 parts of polypropylene resin, 8 parts of maleic anhydride grafted polypropylene, 0.25 parts of hindered phenolic antioxidant 1010 and 0.25 parts of hindered amine light stabilizer 770 according to the weight, add them to a high-speed mixer, and mix at 80°C for 10 minutes to obtain a mixture.

[0055] S3, the mixture is added to a twin-screw extruder for melt blending, and the surface-modified bio-based biodegradable fibers pass through the die. After melt impregnation, granulation, cooling and drying, a bio-based biodegradable continuous fiber reinforced polypropylene composite material is obtained. The barrel temperature of the twin-screw extruder is 160℃ in zone 1, 210℃ in zone 2, 220℃ in zone 3, 230℃ in zone 4, 240℃ in zone 5, 250℃ in zone 6, the die temperature is 250℃, the screw speed is 260r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

[0056] Comparative Example 1

[0057] Compared with Example 1, the pretreatment and surface modification of bio-based biodegradable continuous fibers were not performed, but the other steps were the same, and a composite material was obtained.

[0058] Performance testing

[0059] The standard samples of bio-based biodegradable fiber-reinforced polypropylene composites prepared in Examples 1-3 and Comparative Example 1 were tested according to ISO standards for tensile properties, flexural properties, and impact properties. The test results are shown in Table 1 below.

[0060] Table 1. Performance test results of polypropylene composite materials

[0061]

[0062] As can be seen from Table 1:

[0063] Compared with the comparative example, the bio-based biodegradable fiber-reinforced polypropylene composite material prepared by the present invention has excellent mechanical properties. Compared with the comparative example without fiber pretreatment and surface modification, all mechanical property indicators are significantly improved.

[0064] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0065] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A bio-based biodegradable continuous fiber reinforced polypropylene composite material, characterized in that, Includes the following quantities of raw materials:

2. The bio-based biodegradable continuous fiber reinforced polypropylene composite material according to claim 1, characterized in that, The bio-based biodegradable fibers include: bio-based polymer fibers, cellulose fibers, chitin fibers, polylactic acid fibers, or polycaprolactone fibers.

3. The bio-based biodegradable continuous fiber reinforced polypropylene composite material according to claim 1, characterized in that, The compatibilizer is maleic anhydride-grafted polypropylene.

4. The bio-based biodegradable continuous fiber reinforced polypropylene composite material according to claim 1, characterized in that, The coupling agent is a silane coupling agent.

5. The bio-based biodegradable continuous fiber reinforced polypropylene composite material according to claim 1, characterized in that, The additives include antioxidants and light stabilizers, wherein the antioxidants are hindered phenolic antioxidants and the light stabilizers are hindered amine light stabilizers.

6. A method for preparing a bio-based biodegradable continuous fiber reinforced polypropylene composite material according to any one of claims 1-5, characterized in that, Includes the following steps: S1. After cleaning and drying, the bio-based biodegradable fiber is soaked in sodium hydroxide solution, then rinsed with deionized water until neutral, and dried again to obtain the pretreated bio-based biodegradable fiber. S2, the pretreated bio-based biodegradable fiber is mixed with a coupling agent, an organic solvent is added to react, and then filtered and dried to obtain surface-modified bio-based biodegradable fiber; S3, mix polypropylene resin, compatibilizer and additives to obtain a mixture; S4 involves adding the mixture to a twin-screw extruder for melt blending, with surface-modified biodegradable fibers passing through the die, followed by melt impregnation, granulation, cooling, and drying to obtain a polypropylene composite material.

7. The method for preparing a bio-based biodegradable continuous fiber reinforced polypropylene composite material according to claim 6, characterized in that, The concentration of the sodium hydroxide solution is 5-10 wt%.

8. The method for preparing a bio-based biodegradable continuous fiber reinforced polypropylene composite material according to claim 6, characterized in that, The reaction temperature for mixing bio-based biodegradable fibers with coupling agents is 50-80℃.

9. The method for preparing a bio-based biodegradable continuous fiber reinforced polypropylene composite material according to claim 6, characterized in that, The barrel temperature of the twin-screw extruder is 160℃ in zone 1, 210℃ in zone 2, 220℃ in zone 3, 230℃ in zone 4, 240℃ in zone 5, 250℃ in zone 6, the die temperature is 250℃, the screw speed is 260r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

10. The application of the bio-based biodegradable continuous fiber reinforced polypropylene composite material according to any one of claims 1-5 as a raw material in the preparation of automotive interior parts.

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