A biodegradable antibacterial modified composite fiber material and its preparation method

Abstract

This invention discloses a biodegradable antibacterial modified composite fiber material and its preparation method. The composite fiber material comprises, by weight, 70-90 parts polylactic acid (PLA), 10-30 parts toughening agent, 0.5-2 parts antibacterial agent, 0.2-1 part antioxidant, 0.1-1 part compatibilizer, 0.1-1 part lubricant, and 0.1-1 part anti-hydrolysis agent; wherein the antibacterial agent is nano-silica with quaternization surface modification treatment. The preparation method includes: mixing the components and then melt-extruding them through a twin-screw extruder to obtain modified PLA antibacterial composite chip particles, followed by melt spinning to obtain fibers. This invention solves the problem of decreased antibacterial properties and performance degradation of PLA fibers after dyeing and finishing treatment. The resulting fibers have a breaking strength of 3.32-3.46 cN / dtex and an antibacterial rate of 99.2-99.7%, maintaining excellent performance even after dyeing and finishing treatment, making them suitable for medical, hygiene product, and other fields.

Description

Technical Field

[0001] This invention relates to the field of fiber materials technology, specifically to a biodegradable antibacterial modified composite fiber material and its preparation method. Background Technology

[0002] With increasing environmental awareness, the non-degradability of traditional polymer fibers poses a significant challenge to their recycling and disposal, placing a burden on the ecological environment. Developing biodegradable fibers is an effective way to address this issue. Among these, bio-based materials, represented by polylactic acid (PLA), are gradually becoming a hot topic in the fiber industry due to their green, environmentally friendly, and resource-saving characteristics. PLA fibers possess excellent biocompatibility, skin-friendliness, antibacterial properties, and breathability, making them widely applicable in high-end textile products, medical products, and hygiene products. However, single-component PLA fibers currently still have some limitations; their brittleness, thermal stability, and sustained antibacterial properties restrict their further application in downstream processing and the medical field.

[0003] Chinese patent CN 105077784A discloses a UV-resistant blended fiber, comprising hemp fiber, PLA fiber, milk protein fiber, bamboo pulp fiber, and soybean protein fiber. The resulting blended fiber offers some UV protection, but the overall process is very complex. Chinese patent CN 107541842A blends PLA / PHA composite fiber with silk, achieving a silk-like feel through adjustments to the weaving process. However, this composite fiber has poor strength, and its performance deteriorates significantly after washing. Chinese patent CN 102392318A uses a blend of PLA and PHA to modify the fiber, using PHA to improve the toughness of the PLA fiber. However, due to the simple blending of the two materials, the increased PHA content easily leads to phase separation. The lack of compatibility modification results in incomplete thermodynamic miscibility between the two phases, leading to poor overall material compatibility and heat resistance. Summary of the Invention

[0004] The purpose of this invention is to solve the problem of decreased antibacterial properties and rapid performance degradation of PLA fibers during the downstream dyeing and finishing process. By introducing nano-silica that has undergone quaternization surface modification treatment, not only is the fiber strength improved, but the antibacterial properties of the fiber material are also enhanced, which satisfies the requirements of downstream washing and dyeing and finishing processes while maintaining good fiber stability.

[0005] This invention is implemented through the following technical solutions:

[0006] A biodegradable antibacterial modified composite fiber material, by weight, comprises the following components: 70-90 parts polylactic acid, 10-30 parts toughening agent, 0.5-2 parts antibacterial agent, 0.2-1 part antioxidant, 0.1-1 part compatibilizer, 0.1-1 part lubricant, and 0.1-1 part anti-hydrolysis agent.

[0007] Furthermore, the polylactic acid is L-type and / or D-type polylactic acid with a melt index of 5-30 g / 10 min (190℃, 2.16 kg), preferably Total series LX575, L130, D70 series, Fengyuan FY201, FY601 series.

[0008] Furthermore, the toughening agent is one or more of polybutylene adipate (PBAT), polybutylene succinate (PBS), polycaprolactone (PCL), polypropylene carbonate-polyurethane (PPC-TPU), and polyhydroxyalkanoate (PHA). Preferably, the PHA is PHBH, BP350, BP330 series from Lanjing Microbial Co., Ltd., PCL6500, PCL6800 series from Wuhan Juren, and PCU YX1011 from Jilin Yixian Technology Co., Ltd.

[0009] Furthermore, the antibacterial agent is quaternized surface-modified nano-silica.

[0010] Furthermore, the preparation method of the surface-modified nano silica includes: adding nano SiO2 to a mixture of water and ethanol and stirring, then adding dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, stirring at 25°C for 24 h, and after the reaction is completed, centrifuging to precipitate and washing with distilled water to obtain quaternized surface-modified nano silica.

[0011] Furthermore, the antioxidant is an amine antioxidant and / or a phosphite antioxidant, preferably one or more of antioxidant 1010, antioxidant 168, and antioxidant 1076.

[0012] Further, the compatibilizer is one or more of ADR4468, polyethylene glycol (PEG), cumene peroxide (DCP), and benzoyl peroxide (BPO), preferably BASF's ADR4468, polyethylene glycol, and cumene peroxide.

[0013] Furthermore, the lubricant is one or more of erucamide, oleamide, and stearamide, preferably erucamide or stearamide.

[0014] Furthermore, the anti-hydrolysis agent is monocarboimide and / or carbodiimide, preferably HyMax1010 and HyMax210 from Langyi Company.

[0015] This invention also discloses a method for preparing the biodegradable antibacterial modified composite fiber material, comprising the following steps:

[0016] S1 Preparation of Modified PLA Antibacterial Composite Chip Particles: Weigh the resin and auxiliary materials of each component and add them to a high-speed mixer for mixing. Polylactic acid and toughening agent are mixed in the high-speed mixer at 50-65℃ and 200-400rpm for 1-5min. After uniform mixing, the remaining auxiliary agents are added and mixed in the high-speed mixer at 200-300rpm for 1-2min. After uniform mixing, the mixture is added to the feed hopper of a twin-screw extruder. After melt extrusion, the mixture is drawn out from the die outlet. After cooling, it is pelletized to obtain modified PLA antibacterial composite chip particles. The melt extrusion temperature of the twin-screw extruder is 150-200℃ and the screw speed is 200-400rpm.

[0017] S2 Melt Spinning: The extruded chips are dried in a vacuum spin dryer at 80-100℃ for 2-4 hours to obtain dried chip particles with a moisture content of less than 300ppm. The dried chip particles are then added to a melt spinning extruder for melt spinning. The spinning temperature is 150-210℃, the extrusion rate is 5-30rpm, the draw ratio is 2-4 times, the hot draw temperature is 70-110℃, and the draw speed is 500-2000m / min.

[0018] The beneficial effects of this invention are:

[0019] 1. This invention effectively enhances the antibacterial properties of fibers by adding surface-modified nano-silica, enabling the fibers to maintain good antibacterial effects even after dyeing and finishing. At the same time, nano-silica plays a good linking role between the two-phase resin matrix, improving fiber strength and mechanical properties.

[0020] 2. Surface-modified nano-silica can effectively improve agglomeration and enhance dispersion in resins, forming a dense structure between the material matrix. This not only improves the stability of the fiber spinning process but also prevents solvent damage to the fibers during the downstream dyeing and finishing process.

[0021] 3. The surface-modified antibacterial nano-silica also plays a certain compatibility role, producing a synergistic compatibility enhancement effect with the added compatibility agent, improving fiber strength, reducing the impact of downstream processes on fiber materials, and the dense two-phase structure allows for greater operational space in subsequent fiber spinning processing. Detailed Implementation

[0022] The technical solution of the present invention will be further described in detail below with reference to specific embodiments, but the scope of protection of the present invention is not limited to the following embodiments.

[0023] The antibacterial agent used in the embodiments and comparative examples of this invention is quaternized surface-modified nano-silica. The specific preparation method is as follows: 5g of nano-SiO2 is weighed in an Erlenmeyer flask and added to 500ml of a mixture of water and ethanol (volume ratio 1:1), and stirred electrically for 30min; then 2.5ml of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride is added, and stirred at 25℃ for 24h; after the reaction is completed, the mixture is centrifuged to precipitate, and washed three times with distilled water to remove the solvent remaining on the surface of the nanoparticles, thus obtaining the quaternized surface-modified nano-silica antibacterial agent.

[0024] Example 1

[0025] A biodegradable antibacterial modified composite fiber material and its preparation method, comprising the following steps:

[0026] S1. By weight, weigh 80 parts PLA (brand name LX175, Total Cerberus), 20 parts PHA resin (brand name BP350, Blue Crystal Microbiology), 0.5 parts antibacterial agent, 0.5 parts antioxidant 1010, 0.5 parts compatibilizer (brand name ADR4468, BASF, Germany), 0.2 parts lubricant ethylene bis-stearamide, and 0.5 parts anti-hydrolysis agent HyMax1010 (monomer type, produced by Langyi Company) and add them to a high-speed mixer. Mix at 300 rpm for 3 minutes. After mixing evenly, add the mixture to the feed hopper of a twin-screw extruder. The melt extrusion temperature is 190℃ and the screw speed is 250 rpm. After being melted and extruded by the twin screw, the modified PLA antibacterial composite chip particles are obtained after being drawn, pulled, cooled, and pelletized.

[0027] S2. Add the dried chip particles to a melt spinning extruder for melt spinning. The spinning temperature is 180 / 190 / 190 / 200 / 200 / 200℃, the extrusion rate is 30rpm, the draw ratio is 3.0, the hot draw temperature is 60 / 80 / 100℃, the draw rate is 1000 / 3000m / min, and the fiber bundle size is 100D / 48f.

[0028] Example 2

[0029] The difference between this embodiment and Embodiment 1 is that, by weight, 85 parts of PLA (brand name LX130, Total Cobian), 15 parts of PCL resin (brand name 6500, Hunan Juren), 0.5 parts of antibacterial agent, 0.5 parts of antioxidant 1010, 0.5 parts of compatibilizer (brand name PEG10000, Huisong New Materials), 0.2 parts of lubricant ethylene bis-stearamide, and 0.8 parts of anti-hydrolysis agent HyMax210 (Langyi Company) are weighed out respectively. The remaining steps are the same as in Embodiment 1.

[0030] Example 3

[0031] The difference between this embodiment and Embodiment 1 is that, by weight, 90 parts of PLA (brand name LX130, manufactured by Total Cobian), 10 parts of PPC-TPU resin (brand name YX1011, manufactured by Jilin Yixian Technology), 1 part of antibacterial agent, 0.5 parts of antioxidant 1010, 0.5 parts of antioxidant 168, 0.5 parts of compatibilizer (brand name ADR 4468, manufactured by BASF, Germany), 0.2 parts of lubricant ethylene bis-stearamide, and 0.5 parts of anti-hydrolysis agent HyMax1010 (monomer type, manufactured by Langyi Company) are weighed out respectively. The remaining steps are the same as in Embodiment 1.

[0032] Example 4

[0033] The difference between this embodiment and Embodiment 1 is that, by weight, 85 parts of PLA (brand name FY601, Anhui Fengyuan), 15 parts of PCL resin (brand name 6800, Hunan Juren), 1 part of antibacterial agent, 0.5 parts of antioxidant 1010, 0.5 parts of compatibilizer (brand name PEG10000, Huisong New Materials), 0.2 parts of lubricant ethylene bis-stearamide, and 0.5 parts of anti-hydrolysis agent HyMax210 (polymer type, produced by Langyi Company) are weighed out respectively. The remaining steps are the same as in Embodiment 1.

[0034] Example 5

[0035] The difference between this embodiment and Embodiment 1 is that, by weight, 90 parts of PLA (brand name FY601, Anhui Fengyuan), 10 parts of PHA resin (brand name BP350, Lanjing Microbial), 2 parts of antibacterial agent, 0.5 parts of antioxidant 1010, 0.5 parts of compatibilizer cumene peroxide (brand name LS101-50P, Norion), 0.2 parts of lubricant ethylene bis-stearamide, and 0.5 parts of anti-hydrolysis agent HyMax1010 (monomer type, produced by Langyi Company) are weighed out respectively. The remaining steps are the same as in Embodiment 1.

[0036] Comparative Example 1

[0037] The difference between this comparative example and Example 4 is that no antibacterial agent was added. The components, by weight, include 85 parts PLA (brand name FY601, Anhui Fengyuan), 15 parts PCL resin (brand name 6800, Hunan Juren), 0.5 parts antioxidant 1010, 0.5 parts compatibilizer (brand name PEG10000, Huisong New Materials), 0.2 parts lubricant ethylene bis-stearamide, and 0.5 parts anti-hydrolysis agent HyMax210 (monomer type, produced by Langyi Company). The remaining steps are the same as in Example 1.

[0038] Comparative Example 2

[0039] The difference between this comparative example and Example 5 is that the amount of antibacterial agent is reduced. Its components, by weight, include 90 parts PLA (brand name FY601, produced by Anhui Fengyuan Company), 10 parts PHA resin (brand name BP350, produced by Lanjing Microbiology), 0.2 parts antibacterial agent, 0.5 parts antioxidant 1010, 0.5 parts compatibilizer cumene peroxide (brand name LS101-50P, Norion), 0.2 parts lubricant ethylene bis-stearamide, and 0.5 parts...

[0040] Hydrolysis resistant agent HyMax1010 (monomer type, produced by Langyi Company), the remaining steps are the same as in Example 1.

[0041] Comparative Example 3

[0042] The difference between this comparative example and Example 1 is that the amounts of PLA and toughening agent were adjusted, and the amount of toughening agent was increased. The components, by weight, include 70 parts PLA (brand name LX175, manufactured by Total Cobian), 30 parts PHA resin (brand name BP350, manufactured by Blue Crystal Microbiology), 0.5 parts nano antibacterial agent, 0.5 parts antioxidant 1010, 0.5 parts compatibilizer (brand name ADR 4468, manufactured by BASF, Germany), 0.2 parts lubricant ethylene bis-stearamide, and 0.5 parts anti-hydrolysis agent HyMax1010 (monomer type, manufactured by Langyi Company). The remaining steps are the same as in Example 1.

[0043] Test case

[0044] The performance of the composite fiber materials prepared in the examples and comparative examples was tested, and the performance after dyeing and finishing was also tested. The test results are shown in Table 1.

[0045] Table 1. Performance test results of the examples and comparative examples.

[0046]

[0047] As can be seen from the results in Table 1, the embodiments of the present invention have significantly improved in terms of tensile strength and antibacterial rate compared with the comparative examples, and in particular, they can still maintain excellent performance after dyeing and finishing treatment.

[0048] Finally, it should be noted that the above embodiments are merely illustrative of several implementations of the present invention and are not intended to limit the scope of the invention. For those skilled in the art, any modifications, equivalent substitutions, or improvements made without departing from the concept of the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A biodegradable antibacterial modified composite fiber material, characterized in that, By weight, it includes the following components: 80-90 parts polylactic acid, 10-20 parts toughening agent, 0.5-2 parts antibacterial agent, 0.2-1 part antioxidant, 0.1-1 part compatibilizer, 0.1-1 part lubricant, and 0.1-1 part anti-hydrolysis agent; The antibacterial agent is quaternized surface-modified nano-silica.

2. The biodegradable antibacterial modified composite fiber material according to claim 1, characterized in that: The polylactic acid is L-type and / or D-type polylactic acid, and the melt index measured at 190℃ and 2.16kg is 5-30g / 10min.

3. The biodegradable antibacterial modified composite fiber material according to claim 1, characterized in that: The toughening agent is one or more of the following: polybutylene terephthalate, polybutylene succinate, polyε-caprolactone, polypropylene carbonate-polyurethane, and polyhydroxyalkanoate.

4. The biodegradable antibacterial modified composite fiber material according to claim 1, characterized in that: The preparation method of the surface-modified nano silica includes: adding nano SiO2 into a mixture of water and ethanol and stirring, then adding dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, stirring at 25°C for 24 h, after the reaction is completed, centrifuging to precipitate and washing with distilled water to obtain quaternized surface-modified nano silica.

5. The biodegradable antibacterial modified composite fiber material according to claim 1, characterized in that: The antioxidant is an amine antioxidant and / or a phosphite antioxidant.

6. The biodegradable antibacterial modified composite fiber material according to claim 1, characterized in that: The compatibilizer is one or more of ADR4468, polyethylene glycol, cumene peroxide, and benzoyl peroxide.

7. The biodegradable antibacterial modified composite fiber material according to claim 1, characterized in that: The lubricant is one or more of erucamide, oleamide, and stearamide.

8. The biodegradable antibacterial modified composite fiber material according to claim 1, characterized in that: The anti-hydrolysis agent is monocarboimide and / or carbodiimide.

9. A method for preparing a biodegradable antibacterial modified composite fiber material as described in any one of claims 1 to 8, characterized in that: Includes the following steps: S1 Preparation of Modified PLA Antibacterial Composite Chip Particles: Weigh the resin and auxiliary materials of each component and add them to a high-speed mixer for mixing. Polylactic acid and toughening agent are mixed in the high-speed mixer at 50-65℃ and 200-400rpm for 1-5min. After uniform mixing, the remaining auxiliary agents are added and mixed in the high-speed mixer at 200-300rpm for 1-2min. After uniform mixing, the mixture is added to the feed hopper of a twin-screw extruder. After melt extrusion, the mixture is drawn out from the die outlet. After cooling, it is pelletized to obtain modified PLA antibacterial composite chip particles. The melt extrusion temperature of the twin-screw extruder is 150-200℃ and the screw speed is 200-400rpm. S2 Melt Spinning: The extruded chips are dried in a vacuum spin dryer at 80-100℃ for 2-4 hours to obtain dried chip particles with a moisture content of less than 300ppm. The dried chip particles are then added to a melt spinning extruder for melt spinning. The spinning temperature is 150-210℃, the extrusion rate is 5-30rpm, the draw ratio is 2-4 times, the hot draw temperature is 70-110℃, and the draw speed is 500-2000m / min.

Images