CN-120865686-B - Fiber reinforced polylactic acid composite material and preparation method and application thereof

Abstract

The invention discloses a fiber reinforced polylactic acid composite material, a preparation method and application thereof, and relates to the technical field of fiber materials. The composite material consists of 50-90 parts of polylactic acid matrix, 5-40 parts of polymer fiber, 1-10 parts of plasticizer, 0.5-5 parts of coupling agent and 0.5-5 parts of stabilizer, wherein the stabilizer realizes molecular-level anti-aging protection through deuterated groups and heterocyclic structures, and the polymer fiber is treated by alkali solution to enhance interface combination. The material has excellent toughness and weather resistance, and can be widely applied to the fields of biodegradable medical implantation instruments, high weather-resistant packaging materials and environment-friendly daily necessities.

Inventors

• LI HONGMING
• CHENG HUI
• WANG FAHUI

Assignees

• 无锡南大绿色环境友好材料技术研究院有限公司

Dates

Publication Date

20260508

Application Date

20250715

Claims (8)

1. 1. The fiber reinforced polylactic acid composite material is characterized by comprising, by mass, 50-90 parts of a polylactic acid matrix, 5-40 parts of polymer fibers, 1-10 parts of a plasticizer, 0.5-5 parts of a coupling agent and 0.5-5 parts of a stabilizer; the polymer fiber is selected from any one of polybutylene terephthalate, polyethylene terephthalate and polybutylene succinate, and has the length of 0.1-5mm; the stabilizer has a structure shown in formula 1: Formula 1; The Z 1 is selected from O, S, N (R 1 )、C(CH 3 ) 2 ; The D represents deuterium; R 1 is selected from H, methyl, phenyl, deuterated methyl, deuterated phenyl, deuterated tertiary butyl; The polylactic acid matrix is a blend of polylactic acid and polycaprolactone, wherein the mass ratio of the polylactic acid to the polycaprolactone is 5 parts to 1 part.
2. 2. The fiber reinforced polylactic acid composite according to claim 1, wherein the plasticizer is one or more of glycerin, citrate, or polyethylene glycol.
3. 3. The fiber reinforced polylactic acid composite material according to claim 1, wherein the coupling agent is a silane coupling agent.
4. 4. The fiber reinforced polylactic acid composite according to claim 3, wherein the silane coupling agent is at least one of gamma-aminopropyl triethoxysilane, gamma-glycidoxypropyl trimethoxysilane, and methacryloxypropyl trimethoxysilane.
5. 5. A method for preparing a fiber-reinforced polylactic acid composite according to any one of claims 1 to 4, comprising the steps of: S1, immersing the polymer fibers in an alkali solution with the concentration of 2-10% for treatment for 10-60 minutes, and washing and drying to obtain treated polymer fibers; s2, melt blending the treated polymer fiber with the polylactic acid matrix, the plasticizer, the coupling agent and the stabilizer for 5-30 minutes at 160-200 ℃ to obtain a blend; s3, cooling the blend to room temperature by adopting air cooling to obtain the fiber reinforced polylactic acid composite material.
6. 6. The method for producing a fiber-reinforced polylactic acid composite material according to claim 5, wherein the alkali solution is an aqueous solution of sodium hydroxide or potassium hydroxide, and the treatment temperature is 40 to 80 ℃.
7. 7. The method for producing a fiber-reinforced polylactic acid composite material according to claim 5, wherein the melt blending process is performed in a twin-screw extruder at a screw speed of 50 to 200rpm.
8. 8. Use of a fiber-reinforced polylactic acid composite material according to any one of claims 1-4 for the preparation of biodegradable medical implant materials, packaging materials or commodity products; the medical implant material includes a bone fixation instrument or absorbable suture.

Description

Fiber reinforced polylactic acid composite material and preparation method and application thereof Technical Field The invention relates to the technical field of fiber materials, in particular to a fiber reinforced polylactic acid composite material, a preparation method and application thereof. Background Polylactic acid (PLA) is a novel biodegradable material, and has been attracting attention and increasing in applications in various fields such as packaging, fiber, biomedical and the like due to its good biocompatibility, mechanical properties and recyclability. However, in practical applications, polylactic acid materials still have some bottleneck problems to be solved, especially in terms of aging and toughness. On the one hand, polylactic acid materials have aging problems. Under the conditions of illumination, high temperature or long-term use, etc., ester bonds in the polylactic acid molecular chain are easy to generate hydrolysis or oxidation reaction, so that the molecular weight is reduced, and further the mechanical properties, transparency and the like of the polylactic acid molecular chain are obviously reduced. For example, in the packaging material used outdoors, the polylactic acid product can be subjected to aging phenomena such as embrittlement, discoloration and the like due to long-term exposure to sunlight and air, so that the service life of the material is shortened, and the popularization of the polylactic acid product in some long-term application fields is limited. On the other hand, insufficient toughness is also a major drawback of polylactic acid materials. The pure polylactic acid material is relatively brittle and hard, has relatively high tensile strength and elastic modulus, but has low elongation at break, and is easy to generate brittle fracture when being impacted or acted by large external force. The polylactic acid is limited in application scenes with high requirements on impact resistance, such as fields of automobile parts, medical equipment and the like, and cannot meet actual requirements. Numerous attempts have been made in the industry to address these issues. For example, there is a study to improve the aging performance of polylactic acid by adding an antioxidant, a light stabilizer, etc., which delays the degradation rate of the material to some extent, but these additives tend to have migration problems and may have potential effects on environmental and biosafety. In the aspect of improving toughness, methods such as adding a plasticizer, blending with other polymers and the like are also adopted, and although the elongation at break can be improved to a certain extent, the mechanical strength and the thermal stability of the material can be reduced, the comprehensive performance balance is difficult to achieve, and the diversified requirements of practical application can not be fundamentally met. Therefore, developing a new material and a preparation method capable of effectively solving the problems of polylactic acid aging and insufficient toughness becomes a technical problem to be solved currently. Disclosure of Invention The invention aims at solving the problems existing in the prior art and provides a fiber reinforced polylactic acid composite material with excellent ageing property and toughness, and a preparation method and application thereof. The fiber reinforced polylactic acid composite material comprises, by mass, 50-90 parts of a polylactic acid matrix, 5-40 parts of polymer fibers, 1-10 parts of a plasticizer, 0.5-5 parts of a coupling agent and 0.5-5 parts of a stabilizer; the polymer fiber is selected from any one of polybutylene terephthalate, polyethylene terephthalate and polybutylene succinate, and has the length of 0.1-5mm; the stabilizer has a structure shown in formula 1: The Z 1 is selected from O, S, N (R 1)、C(CH3)2; The D represents deuterium; r 1 is selected from H, methyl, phenyl, deuterated methyl, deuterated phenyl, deuterated tertiary butyl. Further, the stabilizer is selected from any one of the compounds shown in the following structures: further, the synthesis method of the stabilizer comprises the following steps: firstly, synthesizing a raw material 1 and a raw material 2 through suzuki reaction to obtain an intermediate 1; step two, synthesizing the intermediate 1 and the raw material 3 through substitution reaction to obtain an intermediate 2; Thirdly, synthesizing the intermediate 2 through hydroxylation reaction to obtain an intermediate 3; and fourthly, the intermediate 3 and the raw material 4 are synthesized into the stabilizer through Williamson synthesis (Williamson synthesis). Further, the plasticizer is one or more of glycerin, citrate or polyethylene glycol. Further, the coupling agent is a silane coupling agent. Further, the silane coupling agent is at least one of gamma-aminopropyl triethoxysilane, gamma-glycidol ether oxypropyl trimethoxysilane and methacryloxypropyl trimethoxysilane. Further, the po