Antibacterial degradable composite material and application thereof in preparation of fresh food preservation box

Abstract

The invention relates to an antibacterial degradable composite material and application thereof in preparation of a fresh food preservation box, and belongs to the technical field of bio-based composites.The antibacterial degradable composite material is prepared from, by weight, 50-60 parts of comonomers, 15-20 parts of octenyl succinic acid modified starch, 20-25 parts of antibacterial filler, 0.16-0.22 part of lubricant and 0.46-0.52 part of antioxidant; step S2, blending; step S3, performing granulation; step S4, injection molding; the comonomer contains rich active hydroxyl groups, phenyl groups, flexible long-chain alkane structures and unsaturated double bonds, not only can participate in a curing reaction of the poly (butylene succinate), but also can react with the antibacterial filler, so that the overall crosslinking density of the poly (butylene succinate) is improved, the mechanical property of the material is improved, and the antibacterial property of the material is improved. The antibacterial performance and the degradation performance of the material are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of bio-based composite materials, and in particular relates to an antibacterial and degradable composite material and an application thereof in the preparation of a fresh food preservation box. Background Art

[0002] Compared to other polymers, polybutylene succinate (PBSE) is an ideal environmentally friendly material for plastic insulated containers due to its biodegradability, adjustable thermal insulation properties, and potential for modification. Through blending, foaming, and toughening modifications, it can effectively overcome limitations in temperature resistance and mechanical properties, meeting the needs of applications such as cold chain and food packaging. However, the symmetrical segment arrangement of the polybutylene succinate molecular chain leads to enhanced rigidity of the material and limits the local movement ability of the molecular chain, making it difficult for the material to absorb energy through segment slippage or deformation when subjected to stress, resulting in limited inherent mechanical properties of polybutylene succinate. In the prior art, plasticizers are often added to lower the glass transition temperature and increase segment mobility. However, conventional plasticizers have a small molecular weight and cannot participate in the curing reaction. They are prone to migration and precipitation, resulting in poor mechanical properties of the prepared material. At the same time, in order to meet the needs of plastic insulation boxes for cold chain transportation and warehousing of high-value fruits and vegetables, silver ion coatings are often added in the prior art to improve the antibacterial properties of plastic insulation boxes. However, the above-mentioned substrate is not only expensive, but the silver ion coating may also cause a decrease in antibacterial properties due to oxidation or wear.

[0003] Therefore, how to provide an antibacterial biodegradable composite material with high strength, high degradation and good antibacterial properties and its application in the preparation of fresh food preservation boxes is a technical problem that needs to be solved at present. Summary of the Invention

[0004] The purpose of the present invention can be achieved through the following technical solutions: An antibacterial degradable composite material is prepared by the following steps: Step S1, preparing the following raw materials in parts by weight: 50-60 parts of comonomer, 15-20 parts of octenyl succinate starch, 20-25 parts of antibacterial filler, 0.16-0.22 parts of lubricant and 0.46-0.52 parts of antioxidant; Step S2, blending: placing the comonomer, antibacterial filler, lubricant and antioxidant in a high-speed mixer according to parts by weight, and then adding octenyl succinate starch, stirring and mixing for 8-12 minutes to obtain a mixed material; Step S3, granulation: placing the mixture prepared in step S2 in a twin-screw extruder for melt blending, extruding and granulating to obtain blended pellets; Step S4, injection molding: placing the blended pellets obtained in step S3 in an injection molding machine and performing injection molding to obtain an antibacterial and degradable composite material.

[0005] Preferably, the lubricant is at least one of calcium stearate, ethylene bisstearamide and palmitate.

[0006] Preferably, the antioxidant is at least one of tris(2,4-di-tert-butylphenyl)phosphite, dioctadecylthiodipropionate and β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate.

[0007] Preferably, in step S3, the extrusion process of the twin-screw extruder is: zone 1 175-180°C, zone 2 180-185°C, zone 3 185-190°C, zone 4 190-195°C, zone 5 195-200°C, die head temperature 200°C, screw speed 45-55r / min, die head pressure 65-75kg / cm 2 .

[0008] Preferably, in step S4, the temperature of the injection molding machine feed port is 110°C, the temperature of the injection molding machine screw is 120-140°C, and during injection molding, the injection temperatures from the feed port to the discharge port are: first section temperature: 110°C, second section temperature: 100°C, third section temperature: 90°C, fourth section temperature: 80°C, fifth section temperature: 70°C, the injection pressure is 80MPa, and the holding pressure is 40MPa.

[0009] Preferably, an antibacterial degradable composite material is used in a fresh-keeping box.

[0010] Preferably, the comonomer is prepared by the following steps: Under nitrogen protection, the functionalized diol, 1,4-butanediol and dimethyl succinate are uniformly mixed, zinc acetate is added, the temperature is raised to 166-178° C., stirred and reacted for 6-8 hours, and then the temperature is raised to 216-220° C., tetrabutyl titanate is added, the pressure is adjusted to 30-50 Pa, and the polycondensation reaction is carried out for 0.5-0.8 hours to obtain a comonomer, wherein the mass ratio of the functionalized diol, 1,4-butanediol, dimethyl succinate, zinc acetate and tetrabutyl titanate is 3-5:8-12:5.5-8.5:0.04-0.06:0.006-0.01. In the above reaction, zinc acetate is first used as a catalyst to cause the functionalized diol, 1,4-butanediol and dimethyl succinate to undergo ester exchange, and then tetrabutyl titanate is used as a catalyst to cause the obtained product to undergo further polycondensation reaction to obtain a comonomer.

[0011] Preferably, the functionalized diol is prepared by the following steps: Step A1: Vanillin is dissolved in anhydrous THF, and deionized water is added. Under nitrogen protection, sodium percarbonate is added in three equal batches while stirring. The reaction is stirred at room temperature for 2.6-3.2 hours. After the reaction is completed, the pH is adjusted to 3, and the mixture is rotary evaporated, extracted, washed, and dried to obtain a diphenol monomer. The mass ratio of vanillin, anhydrous THF, deionized water, and the total amount of sodium percarbonate is 3-5:100-120:26-30:7.5-12.5. During the above reaction, using anhydrous THF as the solvent and sodium percarbonate as the reducing agent, vanillin is selectively reduced to the diphenol monomer. Step A2: adding a diphenol monomer and tetrabutylammonium bromide to anhydrous DMF, heating the mixture to 45-55° C., stirring uniformly, and adding epichlorohydrin dropwise while stirring. The dropping is completed within 15 minutes. After the dropping is completed, the mixture is heated to 86-94° C., and the mixture is stirred and reacted for 6-8 hours. After the reaction is completed, the mixture is filtered under reduced pressure, washed, and dried to obtain an epoxy monomer. The mass ratio of the diphenol monomer, tetrabutylammonium bromide, anhydrous DMF, and epichlorohydrin is 2.4-4.2:0.02-0.04:70-80:1.6-2.6. During the above reaction, anhydrous DMF is used as a solvent, and the active phenolic hydroxyl groups on the diphenol monomer undergo a bimolecular nucleophilic substitution reaction with epichlorohydrin to obtain the epoxy monomer. During the reaction, the amount of epichlorohydrin is controlled to be slightly lower than that of the diphenol monomer so that the diphenol monomer still has residual phenolic hydroxyl groups that can participate in the subsequent reaction process. Step A3: Add an epoxy monomer, octenylsuccinic anhydride, and p-toluenesulfonic acid to anhydrous DMF, raise the temperature to 76-84° C., stir and react for 3-4 hours, and after the reaction, wash, rotary evaporate, and dry to obtain a functionalized diol. The mass ratio of the epoxy monomer, octenylsuccinic anhydride, p-toluenesulfonic acid, and anhydrous DMF is 2-3.6:1.42-2.68:0.012-0.028:60-80. During the above reaction, using dichloromethane as a solvent, the phenolic hydroxyl group on the epoxy monomer can react with the anhydride group on the octenylsuccinic anhydride through a ring-opening esterification reaction to obtain the functionalized diol. During the above process, the amount of octenylsuccinic anhydride is controlled to be slightly lower than that of the epoxy monomer so that after the reaction, there are still residual epoxy groups that can participate in the subsequent reaction process.

[0012] Preferably, the antibacterial filler is prepared by the following steps: Step B1, drying the nano zinc oxide, then placing it in deionized water, adjusting the pH to 10-11, heating to 50-60°C, ultrasonically dispersing it evenly, adding a mixture of tetrabutyl titanate, urea and deionized water dropwise, and controlling the dripping to be completed within 20 minutes. After the dripping is completed, stirring and reacting for 18-22 minutes, adding a sodium hydroxide aqueous solution, and stirring and reacting for 1.2-1.6 hours at this temperature. After the reaction is completed, filtering, washing, and drying to obtain core-shell particles; The mass ratio of nano-zinc oxide, deionized water, mixed solution a, and sodium hydroxide aqueous solution is 3-5:40-50:24-30:10-14, the mass ratio of tetrabutyl titanate, urea, and deionized water in the mixed solution a is 14-18:2:65-75, and the concentration of the sodium hydroxide aqueous solution is 2-3M. In the above reaction process, anhydrous ethanol is used as a solvent and urea is used as a pore-forming agent to prepare core-shell particles with a nano-zinc oxide core and a titanium dioxide shell and a porous structure. Step B2, ultrasonically mixing the core-shell particles, deionized water, anhydrous ethanol and KH-560 for 18-24 minutes, heating to 46-52 ° C, stirring for 6-8 hours, centrifuging, washing and drying the precipitate to obtain epoxy core-shell particles, ultrasonically dispersing the epoxy core-shell particles and anhydrous DMF, adding tetrabutylammonium bromide, o-hydroxybenzoic acid and anhydrous DMF mixed solution b dropwise, controlling the dripping within 15 minutes, heating to 86-92 ° C, stirring for 5-6 hours, centrifuging, and washing and drying the precipitate to obtain an antibacterial filler, wherein the mass ratio of core-shell particles, deionized water, anhydrous ethanol and KH-560 is 2 .8-3.6:20:46-52:2.4-2.8, the mass ratio of epoxy core-shell particles, anhydrous DMF and mixed liquid b is 2-3:40-46:24, and in the mixed liquid b, the mass ratio of tetrabutylammonium bromide, o-hydroxybenzoic acid and anhydrous DMF is 0.6:1.8-2.2:22-26. In the above reaction process, the core-shell particles are first treated with KH-560, and then under the action of tetrabutylammonium bromide, the carboxyl group of o-hydroxybenzoic acid and the epoxy group undergo a ring-opening esterification reaction to obtain an antibacterial filler. In the above reaction, a rigid structure of benzene ring and a chemically active hydroxyl group are introduced to pave the way for subsequent reactions.

[0013] Compared with the prior art, the present invention has the following beneficial effects: in order to improve the mechanical properties, antibacterial properties and degradation properties of the antibacterial degradable composite material, the present invention starts from two aspects. First, a comonomer is added to the degradable composite material. The comonomer contains rich hydroxyl groups, phenyl groups, flexible long-chain alkane structures and unsaturated double bonds. The presence of hydroxyl groups can, on the one hand, undergo a ring-opening reaction with the epoxy groups of the antibacterial filler, thereby increasing the degree of cross-linking and the dispersion of the antibacterial filler, and improving the mechanical properties and antibacterial properties of the antibacterial degradable composite material. On the other hand, it can produce hydrogen bonds with the hydroxyl groups on the octenyl succinate starch ester and the antibacterial filler, thereby increasing the compatibility and further improving the mechanical properties of the antibacterial degradable composite material. The presence of phenyl groups can serve as a rigid group to further improve the mechanical properties of the antibacterial degradable composite material. The presence of the flexible long-chain alkane structure can, on the one hand, react with the octenyl succinate starch ester to form a hydrogen bond. The entanglement of the alkenyl side chain structure further improves the mechanical properties of the antibacterial and degradable composite material. The presence of unsaturated double bonds can chemically bond with the double bond structure on octenyl succinate starch ester, further improving the mechanical properties of the antibacterial and degradable composite material. Secondly, antibacterial fillers are added. The antibacterial fillers are composed of a core-shell structure. The outer layer is a porous titanium dioxide structure modified by KH-560 and a modified titanium dioxide structure obtained by a ring-opening reaction of o-hydroxybenzoic acid. The inner core is nano-zinc oxide. The presence of nano-zinc oxide and nano-titanium dioxide can not only synergistically exert their own unique physical and chemical properties, but also the grafted o-hydroxybenzoic acid has good antibacterial properties. The hydroxyl group on it can also enhance the catalytic degradation performance of titanium dioxide through the acid catalytic effect. Introducing it into the composite material can synergize with the copolymer monomer to jointly improve the mechanical properties, antibacterial properties and degradation properties of the composite material. DETAILED DESCRIPTION

[0014] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0015] Preparation Examples 1-3 and Comparative Preparation Examples 1-2 provide an antibacterial filler.

[0016] Preparation Example 1 This preparation example provides an antibacterial filler, which is prepared by the following steps: Step B1, placing nano zinc oxide at 70 ° C and drying for 5 hours, then placing it in deionized water, adding 0.8M sodium hydroxide aqueous solution to adjust the pH to 10, heating to 50 ° C, at an ultrasonic frequency of 25 kHz, an ultrasonic power of 400 w, and ultrasonicating for 16 minutes until uniform, adding a mixture of tetrabutyl titanate, urea and deionized water a, controlling the dripping within 20 minutes, stirring at a speed of 600 rpm for 18 minutes, adding 2M sodium hydroxide aqueous solution, maintaining the speed unchanged, keeping warm and stirring for 1.2 hours, filtering, centrifuging, washing with deionized water 3 times, and drying at 60 ° C to constant weight to obtain core-shell particles, wherein the mass ratio of nano zinc oxide, deionized water, mixed solution a and sodium hydroxide aqueous solution is 3:40:24:10, and the mass ratio of tetrabutyl titanate, urea and deionized water in the mixed solution a is 14:2:65; Step B2, the core-shell particles, deionized water, anhydrous ethanol and KH-560 were ultrasonically mixed for 18 minutes, the ultrasonic frequency was controlled to 35kHz, the ultrasonic power was 500W, and at the same time, the temperature was raised to 46 ° C at a speed of 500 rpm, the reaction was stirred for 6 hours, and the precipitate was washed 3 times with anhydrous ethanol and deionized water, and dried at 60 ° C to constant weight to obtain epoxy core-shell particles. The epoxy core-shell particles were ultrasonically dispersed in anhydrous DMF, the ultrasonic frequency was controlled to 25kHz, the ultrasonic power was 400W, the ultrasonic time was 10 minutes, and tetrabutylammonium bromide and o-hydroxybenzoic acid were added dropwise while stirring at a speed of 650 rpm. and anhydrous DMF mixed solution b, and the dripping was controlled within 15 minutes. After the dripping was completed, the temperature was raised to 86°C, the speed was maintained unchanged, and stirring was continued for 5 hours. After the reaction was completed, centrifugation was carried out, and the precipitate was washed three times with a 20% ethanol aqueous solution by mass fraction, and dried at 65°C to constant weight to obtain an antibacterial filler, wherein the mass ratio of core-shell particles, deionized water, anhydrous ethanol and KH-560 was 2.8:20:46:2.4, the mass ratio of epoxy core-shell particles, anhydrous DMF and mixed solution b was 2:40:24, and the mass ratio of tetrabutylammonium bromide, o-hydroxybenzoic acid and anhydrous DMF in the mixed solution b was 0.6:1.8:22.

[0017] Preparation Example 2 This preparation example provides an antibacterial filler, which is prepared by the following steps: Step B1, drying the nano zinc oxide, placing it in deionized water, adding 1.0M sodium hydroxide aqueous solution to adjust the pH to 10.5, heating to 55°C, ultrasonic frequency of 30kHz, ultrasonic power of 450w, ultrasonic for 20min until uniform, adding tetrabutyl titanate, urea and deionized water mixed solution a, controlling the dripping within 20min, after the dripping is completed, stirring at a speed of 650rpm for 20min, adding 2.5M sodium hydroxide aqueous solution, maintaining the speed unchanged, keeping warm and stirring for 1.4h, after the reaction is completed, filtering, washing with deionized water 4 times, and drying at 65°C to constant weight to obtain core-shell particles, wherein the mass ratio of nano zinc oxide, deionized water, mixed solution a and sodium hydroxide aqueous solution is 4:45:27:12, and the mass ratio of tetrabutyl titanate, urea and deionized water in the mixed solution a is 16:2:70; Step B2, the core-shell particles, deionized water, anhydrous ethanol and KH-560 were ultrasonically mixed for 21 minutes, the ultrasonic frequency was controlled to 30kHz, the ultrasonic power was 450w, and at the same time, the temperature was raised to 49 ° C at a speed of 550rpm, the reaction was stirred for 7h, and the precipitate was washed 4 times with anhydrous ethanol and deionized water, and dried at 65 ° C to constant weight to obtain epoxy core-shell particles. The epoxy core-shell particles were ultrasonically dispersed in anhydrous DMF, the ultrasonic frequency was controlled to 30kHz, the ultrasonic power was 450w, the ultrasonic time was 13min, and tetrabutylammonium bromide, o-hydroxybenzoic acid and anhydrous benzoic acid were added dropwise while stirring at a speed of 700rpm. The water-DMF mixture b was controlled to be added within 15 minutes. After the addition was completed, the temperature was raised to 89°C, the speed was maintained unchanged, and stirring was continued for 3.5 hours. After the reaction was completed, centrifugation was performed, and the precipitate was washed four times with a 22% ethanol aqueous solution by mass and dried at 70°C to constant weight to obtain an antibacterial filler, wherein the mass ratio of core-shell particles, deionized water, anhydrous ethanol and KH-560 was 3.2:20:49:2.6, the mass ratio of epoxy core-shell particles, anhydrous DMF and mixture b was 2.5:43:24, and the mass ratio of tetrabutylammonium bromide, o-hydroxybenzoic acid and anhydrous DMF in the mixture b was 0.6:2.0:24.

[0018] Preparation Example 3 This preparation example provides an antibacterial filler, which is prepared by the following steps: Step B1, drying the nano zinc oxide, placing it in deionized water, adding 1.2M sodium hydroxide aqueous solution to adjust the pH to 11, heating to 55°C, at an ultrasonic frequency of 35kHz, an ultrasonic power of 500w, and an ultrasonic time of 20min until uniform, adding a mixture of tetrabutyl titanate, urea and deionized water a, controlling the dripping to be completed within 20min, stirring the reaction at a speed of 700rpm for 22min, adding 3M sodium hydroxide aqueous solution, maintaining the speed unchanged, and stirring the reaction for 1.6h. After the reaction is completed, filtering, washing with deionized water 5 times, and drying at 70°C to constant weight to obtain core-shell particles, wherein the mass ratio of nano zinc oxide, deionized water, mixed solution a and sodium hydroxide aqueous solution is 5:50:30:14, and the mass ratio of tetrabutyl titanate, urea and deionized water in the mixed solution a is 18:2:75; Step B2, the core-shell particles, deionized water, anhydrous ethanol and KH-560 were ultrasonically mixed for 24 minutes, the ultrasonic frequency was controlled to 25kHz, the ultrasonic power was 400w, and at the same time, the temperature was raised to 52°C at a speed of 600rpm, the reaction was stirred for 8 hours, and the precipitate was washed 5 times with anhydrous ethanol and deionized water, and dried at 70°C to constant weight to obtain epoxy core-shell particles. The epoxy core-shell particles were ultrasonically dispersed in anhydrous DMF, the ultrasonic frequency was controlled to 35kHz, the ultrasonic power was 500w, the ultrasonic time was 16min, and tetrabutylammonium bromide and o-hydroxybenzoic acid were added dropwise while stirring at a speed of 750rpm. and anhydrous DMF mixed solution b, and the dripping was controlled within 15 minutes. After the dripping was completed, the temperature was raised to 92°C, the speed was maintained unchanged, and stirring was continued for 4 hours. After the reaction was completed, centrifugation was carried out, and the precipitate was washed 5 times with a 24% ethanol aqueous solution by mass fraction, and dried at 75°C to constant weight to obtain an antibacterial filler, wherein the mass ratio of core-shell particles, deionized water, anhydrous ethanol and KH-560 was 3.6:20:52:2.8, the mass ratio of epoxy core-shell particles, anhydrous DMF and mixed solution b was 3:46:24, and the mass ratio of tetrabutylammonium bromide, o-hydroxybenzoic acid and anhydrous DMF in the mixed solution b was 0.6:2.2:26.

[0019] Comparative Preparation Example 1 This comparative preparation example provides an antibacterial filler, which is prepared by the following steps: Step B1, placing nano zinc oxide at 70 ° C and drying for 5 hours, then placing it in deionized water, adding 0.8M sodium hydroxide aqueous solution to adjust the pH to 10, heating to 50 ° C, at an ultrasonic frequency of 25 kHz, an ultrasonic power of 400 w, and ultrasonicating for 16 minutes until uniform, adding a mixture of tetrabutyl titanate, urea and deionized water a, controlling the dripping within 20 minutes, stirring at a speed of 600 rpm for 18 minutes, adding 2M sodium hydroxide aqueous solution, maintaining the speed unchanged, keeping warm and stirring for 1.2 hours, filtering, centrifuging, washing with deionized water 3 times, and drying at 60 ° C to constant weight to obtain core-shell particles, wherein the mass ratio of nano zinc oxide, deionized water, mixed solution a and sodium hydroxide aqueous solution is 3:40:24:10, and the mass ratio of tetrabutyl titanate, urea and deionized water in the mixed solution a is 14:2:65; Step B2, the core-shell particles, deionized water, anhydrous ethanol and KH-560 were ultrasonically mixed for 18 minutes, the ultrasonic frequency was controlled to 35kHz, the ultrasonic power was 500w, and at the same time, the temperature was raised to 46 ° C at a speed of 500rpm, and the reaction was stirred for 6 hours. The precipitate was washed with anhydrous ethanol and deionized water 3 times and dried at 60 ° C to constant weight to obtain epoxy core-shell particles. The epoxy core-shell particles were ultrasonically dispersed in anhydrous DMF, the ultrasonic frequency was controlled to 25kHz, the ultrasonic power was 400w, and the ultrasonic time was 10min. Tetrabutylammonium bromide and benzoic acid were added dropwise while stirring at a speed of 650rpm. and anhydrous DMF mixed solution b, and the dripping was controlled within 15 minutes. After the dripping was completed, the temperature was raised to 86°C, the speed was maintained unchanged, and stirring was continued for 5 hours. After the reaction was completed, centrifugation was carried out, and the precipitate was washed three times with a 20% ethanol aqueous solution by mass fraction, and dried at 65°C to constant weight to obtain an antibacterial filler, wherein the mass ratio of core-shell particles, deionized water, anhydrous ethanol and KH-560 was 2.8:20:46:2.4, the mass ratio of epoxy core-shell particles, anhydrous DMF and mixed solution b was 2:40:24, and the mass ratio of tetrabutylammonium bromide, benzoic acid and anhydrous DMF in the mixed solution b was 0.6:1.8:22.

[0020] Comparative Preparation Example 2 This comparative preparation example provides an antibacterial filler, which is prepared by the following steps: Step B1, placing nano zinc oxide at 70 ° C and drying for 5 hours, then placing it in deionized water, adding 0.8M sodium hydroxide aqueous solution to adjust the pH to 10, heating to 50 ° C, at an ultrasonic frequency of 25 kHz, an ultrasonic power of 400 w, and ultrasonicating for 16 minutes until uniform, adding a mixture of tetrabutyl titanate, urea and deionized water a, controlling the dripping within 20 minutes, stirring at a speed of 600 rpm for 18 minutes, adding 2M sodium hydroxide aqueous solution, maintaining the speed unchanged, keeping warm and stirring for 1.2 hours, filtering, centrifuging, washing with deionized water 3 times, and drying at 60 ° C to constant weight to obtain core-shell particles, wherein the mass ratio of nano zinc oxide, deionized water, mixed solution a and sodium hydroxide aqueous solution is 3:40:24:10, and the mass ratio of tetrabutyl titanate, urea and deionized water in the mixed solution a is 14:2:65; Step B2, the core-shell particles, deionized water, anhydrous ethanol and KH-560 were ultrasonically mixed for 18 minutes, the ultrasonic frequency was controlled to 35kHz, the ultrasonic power was 500W, and at the same time, the temperature was raised to 46°C at a speed of 500rpm, the reaction was stirred for 6 hours, and the precipitate was washed 3 times with anhydrous ethanol and deionized water, and dried at 60°C to constant weight to obtain epoxy core-shell particles. The epoxy core-shell particles were ultrasonically dispersed in anhydrous DMF, the ultrasonic frequency was controlled to 25kHz, the ultrasonic power was 400W, the ultrasonic time was 10min, and tetrabutylammonium bromide and 2,3-dihydroxypropionic acid were added dropwise while stirring at a speed of 650rpm. and anhydrous DMF mixed solution b, and the dripping was controlled within 15 minutes. After the dripping was completed, the temperature was raised to 86°C, the speed was maintained unchanged, and stirring was continued for 5 hours. After the reaction was completed, centrifugation was carried out, and the precipitate was washed three times with a 20% ethanol aqueous solution by mass fraction, and dried at 65°C to constant weight to obtain an antibacterial filler, wherein the mass ratio of core-shell particles, deionized water, anhydrous ethanol and KH-560 was 2.8:20:46:2.4, the mass ratio of epoxy core-shell particles, anhydrous DMF and mixed solution b was 2:40:24, and the mass ratio of tetrabutylammonium bromide, 2,3-dihydroxypropionic acid and anhydrous DMF in the mixed solution b was 0.6:1.8:22.

[0021] Preparation Examples 4-6 and Comparative Preparation Examples 3-5 provide a functionalized diol.

[0022] Preparation Example 4 This preparation example provides a functionalized diol, which is prepared by the following steps: Step A1: Vanillin was dissolved in anhydrous THF, and deionized water was added. Under nitrogen protection, sodium percarbonate was added in three equal batches with stirring, with an interval of 3 minutes between each batch. The rotation speed was controlled at 600 rpm, and the reaction was stirred at room temperature for 2.6 hours. After the reaction, the pH was adjusted to 3 with 0.6M hydrochloric acid aqueous solution, and the rotary evaporation temperature was controlled at 42°C to remove the anhydrous THF. The mixture was extracted with ethyl acetate three times, and then washed with saturated brine three times. The organic layer was dried over anhydrous sodium sulfate to obtain a diphenol monomer, wherein the mass ratio of vanillin, anhydrous THF, deionized water, and the total amount of sodium percarbonate was 3:100:26:7.5; Step A2, adding a diphenol monomer and tetrabutylammonium bromide to anhydrous DMF, heating to 45°C, controlling the speed to 640 rpm and stirring for 12 minutes until uniform, adding epichlorohydrin dropwise while stirring, and controlling the dripping to be completed within 15 minutes. After the dripping is completed, heating to 86°C, maintaining the speed unchanged, and continuing to stir and react for 6 hours. After the reaction is completed, filtering under reduced pressure, washing with anhydrous ethanol and deionized water three times, and drying at 55°C to constant weight to obtain an epoxy monomer, wherein the mass ratio of diphenol monomer, tetrabutylammonium bromide, anhydrous DMF and epichlorohydrin is 2.4:0.02:70:1.6; Step A3: Add anhydrous DMF to an epoxy monomer, octenylsuccinic anhydride, and p-toluenesulfonic acid, raise the temperature to 76°C, and stir the reaction at a speed of 550 rpm for 3 hours. After the reaction, control the rotary evaporation temperature to 82°C to remove the anhydrous DMF, then wash three times with saturated brine, and dry the organic layer with anhydrous sodium sulfate to obtain a functionalized diol, wherein the mass ratio of epoxy monomer, octenylsuccinic anhydride, p-toluenesulfonic acid, and anhydrous DMF is 2:1.42:0.012:60.

[0023] Preparation Example 5 This preparation example provides a functionalized diol, which is prepared by the following steps: Step A1, dissolving vanillin in anhydrous THF, then adding deionized water, and under nitrogen protection, adding sodium percarbonate in three equal batches while stirring, with an interval of 5 minutes between each batch, and reacting at room temperature for 2.9 hours. After the reaction, adjusting the pH to 3 with 0.8M hydrochloric acid aqueous solution, controlling the rotary evaporation temperature to 46°C to remove the anhydrous THF, extracting with ethyl acetate four times, and then washing with saturated brine four times. The organic layer is dried over anhydrous sodium sulfate to obtain a diphenol monomer, wherein the mass ratio of vanillin, anhydrous THF, deionized water, and the total amount of sodium percarbonate is 4:110:28:10; Step A2, adding a diphenol monomer and tetrabutylammonium bromide to anhydrous DMF, heating to 50°C, controlling the speed to 660 rpm and stirring for 16 minutes until uniform, adding epichlorohydrin dropwise while stirring, and controlling the dripping to be completed within 15 minutes. After the dripping is completed, heating to 90°C, continuing to stir and react for 7 hours. After the reaction is completed, filtering under reduced pressure, washing with anhydrous ethanol and deionized water 4 times, and drying at 60°C to constant weight to obtain an epoxy monomer, wherein the mass ratio of diphenol monomer, tetrabutylammonium bromide, anhydrous DMF and epichlorohydrin is 3.3:0.03:75:2.1; Step A3: Add anhydrous DMF to an epoxy monomer, octenylsuccinic anhydride, and p-toluenesulfonic acid, raise the temperature to 80°C, control the speed to 580 rpm, and stir the reaction for 3.5 hours. Control the rotary evaporation temperature to 84°C to remove the anhydrous DMF, then wash with saturated brine four times, and dry the organic layer with anhydrous sodium sulfate to obtain a functionalized diol, wherein the mass ratio of epoxy monomer, octenylsuccinic anhydride, p-toluenesulfonic acid, and anhydrous DMF is 2.8:2.05:0.020:70.

[0024] Preparation Example 6 This preparation example provides a functionalized diol, which is prepared by the following steps: Step A1, dissolving vanillin in anhydrous THF, then adding deionized water, and under nitrogen protection, adding sodium percarbonate in three equal batches while stirring, with an interval of 7 minutes between each batch, and reacting at room temperature for 3.2 hours. After the reaction, adjusting the pH to 3 with a 1.0M hydrochloric acid solution, controlling the rotary evaporation temperature to 50°C to remove the anhydrous THF, extracting with ethyl acetate five times, and then washing with saturated brine five times. The organic layer is dried over anhydrous sodium sulfate to obtain a diphenol monomer, wherein the mass ratio of vanillin, anhydrous THF, deionized water, and the total amount of sodium percarbonate is 5:120:30:12.5; Step A2, adding a diphenol monomer and tetrabutylammonium bromide to anhydrous DMF, heating to 55°C, controlling the speed to 680 rpm and stirring for 20 minutes until uniform, adding epichlorohydrin dropwise while stirring, and controlling the dripping to be completed within 15 minutes. After the dripping is completed, heating to 94°C, continuing to stir and react for 8 hours. After the reaction is completed, filtering under reduced pressure, washing with anhydrous ethanol and deionized water 5 times, and drying at 65°C to constant weight to obtain an epoxy monomer, wherein the mass ratio of diphenol monomer, tetrabutylammonium bromide, anhydrous DMF and epichlorohydrin is 4.2:0.04:80:2.6; Step A3: Add anhydrous DMF to an epoxy monomer, octenylsuccinic anhydride, and p-toluenesulfonic acid, raise the temperature to 84°C, control the speed to 610 rpm, and stir to react for 4 hours. After the reaction, control the rotary evaporation temperature to 86°C to remove the anhydrous DMF, then wash with saturated brine 5 times, and dry the organic layer with anhydrous sodium sulfate to obtain a functionalized diol, wherein the mass ratio of epoxy monomer, octenylsuccinic anhydride, p-toluenesulfonic acid, and anhydrous DMF is 3.6:2.68:0.028:80.

[0025] Comparative Preparation Example 3 This comparative preparation example provides a functionalized diol, which is prepared by the following steps: Step A1: Vanillin was dissolved in anhydrous THF, and deionized water was added. Under nitrogen protection, sodium percarbonate was added in three equal batches with stirring, with an interval of 3 minutes between each batch. The rotation speed was controlled at 600 rpm, and the reaction was stirred at room temperature for 2.6 hours. After the reaction, the pH was adjusted to 3 with 0.6M hydrochloric acid aqueous solution, and the rotary evaporation temperature was controlled at 42°C to remove the anhydrous THF. The mixture was extracted with ethyl acetate three times, and then washed with saturated brine three times. The organic layer was dried over anhydrous sodium sulfate to obtain a diphenol monomer, wherein the mass ratio of vanillin, anhydrous THF, deionized water, and the total amount of sodium percarbonate was 3:100:26:7.5; Step A2, adding a diphenol monomer and tetrabutylammonium bromide to anhydrous DMF, heating to 45°C, controlling the speed to 640 rpm and stirring for 12 minutes until uniform, adding epichlorohydrin dropwise while stirring, and controlling the dripping to be completed within 15 minutes. After the dripping is completed, heating to 86°C, maintaining the speed unchanged, and continuing to stir and react for 6 hours. After the reaction is completed, filtering under reduced pressure, washing with anhydrous ethanol and deionized water three times, and drying at 55°C to constant weight to obtain an epoxy monomer, wherein the mass ratio of diphenol monomer, tetrabutylammonium bromide, anhydrous DMF and epichlorohydrin is 2.4:0.02:70:1.6; Step A3: Add epoxy monomer, itaconic anhydride and p-toluenesulfonic acid to anhydrous DMF, raise the temperature to 76°C, control the speed to 550 rpm and stir to react for 3 hours. After the reaction, control the rotary evaporation temperature to 82°C to remove anhydrous DMF, then wash with saturated brine three times, and dry the organic layer with anhydrous sodium sulfate to obtain a functionalized diol, wherein the mass ratio of epoxy monomer, itaconic anhydride, p-toluenesulfonic acid and anhydrous DMF is 2:1.42:0.012:60.

[0026] Comparative Preparation Example 4 This comparative preparation example provides a functionalized diol, which is prepared by the following steps: Step A1: Vanillin was dissolved in anhydrous THF, and deionized water was added. Under nitrogen protection, sodium percarbonate was added in three equal batches with stirring, with an interval of 3 minutes between each batch. The rotation speed was controlled at 600 rpm, and the reaction was stirred at room temperature for 2.6 hours. After the reaction, the pH was adjusted to 3 with 0.6M hydrochloric acid aqueous solution, and the rotary evaporation temperature was controlled at 42°C to remove the anhydrous THF. The mixture was extracted with ethyl acetate three times, and then washed with saturated brine three times. The organic layer was dried over anhydrous sodium sulfate to obtain a diphenol monomer, wherein the mass ratio of vanillin, anhydrous THF, deionized water, and the total amount of sodium percarbonate was 3:100:26:7.5; Step A2, adding a diphenol monomer and tetrabutylammonium bromide to anhydrous DMF, heating to 45°C, controlling the speed to 640 rpm and stirring for 12 minutes until uniform, adding epichlorohydrin dropwise while stirring, and controlling the dripping to be completed within 15 minutes. After the dripping is completed, heating to 86°C, maintaining the speed unchanged, and continuing to stir and react for 6 hours. After the reaction is completed, filtering under reduced pressure, washing with anhydrous ethanol and deionized water three times, and drying at 55°C to constant weight to obtain an epoxy monomer, wherein the mass ratio of diphenol monomer, tetrabutylammonium bromide, anhydrous DMF and epichlorohydrin is 2.4:0.02:70:1.6; Step A3: Add anhydrous DMF to an epoxy monomer, n-octylsuccinic anhydride, and p-toluenesulfonic acid, raise the temperature to 76°C, and stir the reaction at a speed of 550 rpm for 3 hours. After the reaction, control the rotary evaporation temperature to 82°C to remove the anhydrous DMF, then wash three times with saturated brine, and dry the organic layer with anhydrous sodium sulfate to obtain a functionalized diol, wherein the mass ratio of epoxy monomer, n-octylsuccinic anhydride, p-toluenesulfonic acid, and anhydrous DMF is 2:1.42:0.012:60.

[0027] Comparative Preparation Example 5 This comparative preparation example provides a functionalized diol, which is prepared by the following steps: Step A1, citral was dissolved in anhydrous THF, and then deionized water was added. Under nitrogen protection, sodium percarbonate was added in three equal batches while stirring, with an interval of 3 minutes between each batch. The rotation speed was controlled at 600 rpm, and the reaction was stirred at room temperature for 2.6 hours. After the reaction, the pH was adjusted to 3 with 0.6M hydrochloric acid aqueous solution, and the rotary evaporation temperature was controlled at 42°C to remove anhydrous THF. The mixture was extracted with ethyl acetate three times, and then washed with saturated brine three times. The organic layer was dried over anhydrous sodium sulfate to obtain a diphenol monomer, wherein the mass ratio of citral, anhydrous THF, deionized water and the total amount of sodium percarbonate was 3:100:26:7.5; Step A2, adding a diphenol monomer and tetrabutylammonium bromide to anhydrous DMF, heating to 45°C, controlling the speed to 640 rpm and stirring for 12 minutes until uniform, adding epichlorohydrin dropwise while stirring, and controlling the dripping to be completed within 15 minutes. After the dripping is completed, heating to 86°C, maintaining the speed unchanged, and continuing to stir and react for 6 hours. After the reaction is completed, filtering under reduced pressure, washing with anhydrous ethanol and deionized water three times, and drying at 55°C to constant weight to obtain an epoxy monomer, wherein the mass ratio of diphenol monomer, tetrabutylammonium bromide, anhydrous DMF and epichlorohydrin is 2.4:0.02:70:1.6; Step A3: Add anhydrous DMF to an epoxy monomer, octenylsuccinic anhydride, and p-toluenesulfonic acid, raise the temperature to 76°C, and stir the reaction at a speed of 550 rpm for 3 hours. After the reaction, control the rotary evaporation temperature to 82°C to remove the anhydrous DMF, then wash three times with saturated brine, and dry the organic layer with anhydrous sodium sulfate to obtain a functionalized diol, wherein the mass ratio of epoxy monomer, octenylsuccinic anhydride, p-toluenesulfonic acid, and anhydrous DMF is 2:1.42:0.012:60.

[0028] Preparation Examples 7-9 and Comparative Preparation Examples 6-8 provide a method for preparing a comonomer.

[0029] Preparation Example 7 This preparation example provides a comonomer, which is prepared by the following steps: Under nitrogen protection, the functionalized diol prepared in Preparation Example 4, 1,4-butanediol and dimethyl succinate were stirred at a speed of 650 rpm for 16 min until uniformly mixed, zinc acetate was added, the temperature was raised to 166°C, the speed was maintained unchanged, and the stirring reaction was continued for 6 h. The temperature was then raised to 216°C, tetrabutyl titanate was added, the pressure was adjusted to 30 Pa, and the polycondensation reaction was carried out for 0.5 h to obtain a comonomer, wherein the mass ratio of the functionalized diol, 1,4-butanediol, dimethyl succinate, zinc acetate and tetrabutyl titanate was 3:8:5.5:0.04:0.006.

[0030] Preparation Example 8 This preparation example provides a comonomer, which is prepared by the following steps: Under nitrogen protection, the functionalized diol prepared in Preparation Example 5, 1,4-butanediol and dimethyl succinate were stirred at a speed of 680 rpm for 18 min until uniformly mixed, zinc acetate was added, the temperature was raised to 172°C, the speed was maintained constant, and the stirring reaction was continued for 7 h. The temperature was then raised to 218°C, tetrabutyl titanate was added, the pressure was adjusted to 40 Pa, and the polycondensation reaction was carried out for 0.65 h to obtain a comonomer, wherein the mass ratio of the functionalized diol, 1,4-butanediol, dimethyl succinate, zinc acetate and tetrabutyl titanate was 4:10:7.0:0.05:0.008.

[0031] Preparation Example 9 This preparation example provides a comonomer, which is prepared by the following steps: Under nitrogen protection, the functionalized diol prepared in Preparation Example 6, 1,4-butanediol and dimethyl succinate were stirred at a speed of 710 rpm for 20 min until uniformly mixed, zinc acetate was added, the temperature was raised to 178°C, the speed was maintained unchanged, and the stirring reaction was continued for 8 hours. The temperature was then raised to 220°C, tetrabutyl titanate was added, the pressure was adjusted to 50 Pa, and the polycondensation reaction was carried out for 0.8 hours to obtain a comonomer, wherein the mass ratio of the functionalized diol, 1,4-butanediol, dimethyl succinate, zinc acetate and tetrabutyl titanate was 5:12:8.5:0.06:0.01.

[0032] Comparative Preparation Example 6 This comparative preparation example provides a comonomer, which is prepared by the following steps: Under nitrogen protection, the functionalized diol, 1,4-butanediol and dimethyl succinate prepared in Comparative Preparation Example 3 were stirred at a speed of 650 rpm for 16 min until uniformly mixed, zinc acetate was added, the temperature was raised to 166 ° C, the speed was maintained unchanged, and the stirring reaction was continued for 6 h. The temperature was then raised to 216 ° C, tetrabutyl titanate was added, the pressure was adjusted to 30 Pa, and the polycondensation reaction was carried out for 0.5 h to obtain a comonomer, wherein the mass ratio of the functionalized diol, 1,4-butanediol, dimethyl succinate, zinc acetate and tetrabutyl titanate was 3:8:5.5:0.04:0.006.

[0033] Comparative Preparation Example 7 This comparative preparation example provides a comonomer, which is prepared by the following steps: Under nitrogen protection, the functionalized diol, 1,4-butanediol and dimethyl succinate prepared in Comparative Preparation Example 4 were stirred at a speed of 650 rpm for 16 min until uniformly mixed, zinc acetate was added, the temperature was raised to 166 ° C, the speed was maintained unchanged, and the stirring reaction was continued for 6 h. The temperature was then raised to 216 ° C, tetrabutyl titanate was added, the pressure was adjusted to 30 Pa, and the polycondensation reaction was carried out for 0.5 h to obtain a comonomer, wherein the mass ratio of the functionalized diol, 1,4-butanediol, dimethyl succinate, zinc acetate and tetrabutyl titanate was 3:8:5.5:0.04:0.006.

[0034] Comparative Preparation Example 8 This comparative preparation example provides a comonomer, which is prepared by the following steps: Under nitrogen protection, the functionalized diol, 1,4-butanediol and dimethyl succinate prepared in Comparative Preparation Example 5 were stirred at a speed of 650 rpm for 16 min until uniformly mixed, zinc acetate was added, the temperature was raised to 166 ° C, the speed was maintained unchanged, and the stirring reaction was continued for 6 h. The temperature was then raised to 216 ° C, tetrabutyl titanate was added, the pressure was adjusted to 30 Pa, and the polycondensation reaction was carried out for 0.5 h to obtain a comonomer, wherein the mass ratio of the functionalized diol, 1,4-butanediol, dimethyl succinate, zinc acetate and tetrabutyl titanate was 3:8:5.5:0.04:0.006.

[0035] Examples 1-3 and Comparative Examples 1-5 provide an antibacterial and degradable composite material.

[0036] Example 1 This embodiment provides an antibacterial biodegradable composite material, which is prepared by the following steps: Step S1, preparing the following raw materials in parts by weight: 50 parts of the comonomer prepared in Preparation Example 7, 15 parts of octenyl succinate starch, 20 parts of the antibacterial filler prepared in Preparation Example 1, 0.16 parts of calcium stearate, and 0.46 parts of tris(2,4-di-tert-butylphenyl)phosphite; Step S2, blending: placing the comonomer, antibacterial filler, calcium stearate and tris(2,4-di-tert-butylphenyl)phosphite in a high-speed mixer according to weight, then adding octenyl succinate starch, controlling the speed to 1300 rpm, stirring and mixing for 8 minutes to obtain a mixed material; Step S3, granulation: The mixed material prepared in step S2 is placed in a twin-screw extruder for melt blending and extrusion granulation to obtain blended granules, wherein the extrusion process of the twin-screw extruder is as follows: zone 1 175°C, zone 2 180°C, zone 3 185°C, zone 4 190°C, zone 5 195°C, die head temperature 200°C, screw speed 45r / min, die head pressure 65kg / cm 2 ; Step S4, injection molding: placing the blended pellets obtained in step S3 in an injection molding machine, injection molding, to obtain an antibacterial and degradable composite material, the injection molding machine feed port temperature is 110 ° C, the injection molding machine screw temperature is 120 ° C, during injection molding, the injection temperatures from the feed port to the discharge port are: first section temperature: 110 ° C, second section temperature: 100 ° C, third section temperature: 90 ° C, fourth section temperature: 80 ° C, fifth section temperature: 70 ° C, the injection pressure is 80 MPa, and the holding pressure is 40 MPa.

[0037] Example 2 This embodiment provides an antibacterial biodegradable composite material, which is prepared by the following steps: Step S1, preparing the following raw materials in parts by weight: 55 parts of the comonomer prepared in Preparation Example 8, 17.5 parts of octenyl succinate starch, 22.5 parts of the antibacterial filler prepared in Preparation Example 2, 0.19 parts of ethylene bisstearamide, and 0.49 parts of dioctadecyl thiodipropionate; Step S2, blending: placing the comonomer, antibacterial filler, ethylene bisstearamide and dioctadecyl thiodipropionate in a high-speed mixer according to parts by weight, then adding octenyl succinate starch, controlling the speed to 1400 rpm, stirring and mixing for 10 minutes to obtain a mixed material; Step S3, granulation: The mixed material prepared in step S2 is placed in a twin-screw extruder for melt blending and extrusion granulation to obtain blended granules, wherein the extrusion process of the twin-screw extruder is as follows: zone 1 178°C, zone 2 183°C, zone 3 188°C, zone 4 193°C, zone 5 198°C, die head temperature 200°C, screw speed 50r / min, die head pressure 70kg / cm 2 ; Step S4, injection molding: placing the blended pellets obtained in step S3 in an injection molding machine and injection molding to obtain an antibacterial and degradable composite material, wherein the feed port temperature of the injection molding machine is 110°C, and the screw temperature of the injection molding machine is 130°C. During injection molding, the injection temperatures from the feed port to the discharge port are: first section temperature: 110°C, second section temperature: 100°C, third section temperature: 90°C, fourth section temperature: 80°C, fifth section temperature: 70°C, the injection pressure is 80 MPa, and the holding pressure is 40 MPa.

[0038] Example 3 This embodiment provides an antibacterial and degradable composite material, which is prepared by the following steps: Step S1, preparing the following raw materials in parts by weight: 60 parts of the comonomer prepared in Preparation Example 9, 20 parts of octenyl succinate starch, 25 parts of the antibacterial filler prepared in Preparation Example 3, 0.22 parts of palmitic acid ester, and 0.52 parts of β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate; Step S2, blending: placing the comonomer, antibacterial filler, palmitate and β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate into a high-speed mixer according to parts by weight, then adding octenyl succinate starch, controlling the speed to 1500 rpm, and stirring and mixing for 12 minutes to obtain a mixed material; Step S3, granulation: The mixed material prepared in step S2 is placed in a twin-screw extruder for melt blending and extrusion granulation to obtain blended granules, wherein the extrusion process of the twin-screw extruder is as follows: zone 1 180°C, zone 2 185°C, zone 3 190°C, zone 4 195°C, zone 5 200°C, die head temperature 200°C, screw speed 55r / min, die head pressure 75kg / cm 2 ; Step S4, injection molding: placing the blended pellets obtained in step S3 in an injection molding machine and injection molding to obtain an antibacterial and degradable composite material, wherein the feed port temperature of the injection molding machine is 110°C, and the screw temperature of the injection molding machine is 120-140°C. During injection molding, the injection temperatures from the feed port to the discharge port are: first section temperature: 110°C, second section temperature: 100°C, third section temperature: 90°C, fourth section temperature: 80°C, fifth section temperature: 70°C, the injection pressure is 80 MPa, and the holding pressure is 40 MPa.

[0039] Comparative Example 1 The only difference between Comparative Example 1 and Example 1 is that the comonomer in Example 1 is replaced by the comonomer prepared in Comparative Preparation Example 6.

[0040] Comparative Example 2 The only difference between Comparative Example 2 and Example 1 is that the comonomer in Example 1 is replaced by the comonomer prepared in Comparative Preparation Example 7.

[0041] Comparative Example 3 The only difference between Comparative Example 3 and Example 1 is that the comonomer in Example 1 is replaced by the comonomer prepared in Comparative Preparation Example 8.

[0042] Comparative Example 4 The only difference between Comparative Example 4 and Example 1 is that the antibacterial filler in Example 1 is replaced by the antibacterial filler prepared in Comparative Preparation Example 1.

[0043] Comparative Example 5 The only difference between Comparative Example 5 and Example 1 is that the antibacterial filler in Example 1 is replaced by the antibacterial filler prepared in Comparative Preparation Example 2.

[0044] Performance testing Mechanical properties test: The tensile strength and elongation at break of the antibacterial degradable composite materials prepared in Examples 1-3 and Comparative Examples 1-5 were measured using the ISO527 standard; the unnotched impact strength was measured using the ISO180 standard; Antibacterial performance test: The antibacterial degradable composite materials with a diameter of 5 mm prepared in Examples 1-3 and Comparative Examples 1-5 were respectively applied to an agar plate. 0.5 mL of a 106 cell / mL Escherichia coli droplet was evenly spread on the plate. The plate was then placed in a constant temperature incubator at 37°C for 24 h, and the diameter of the inhibition zone was observed and measured. Biodegradability test: The performance of the 5 mm diameter antibacterial biodegradable composite materials prepared in Examples 1-3 and Comparative Examples 1-5 was tested using the ISO 14855 standard. The specific test results are shown in Table 1 below: Table 1 Performance test of antibacterial degradable composite materials in Examples 1-3 and Comparative Examples 1-5

[0045] It can be seen from Table 1 that, compared with Comparative Examples 1-5, the antibacterial and degradable composite materials prepared in Examples 1-3 have more excellent mechanical properties, antibacterial properties and degradation properties.

[0046] Throughout the specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these 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 any one or more embodiments or examples.

[0047] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. An antibacterial degradable composite material, characterized in that: Prepared by the following steps: Step S1, preparing the following raw materials in parts by weight: 50-60 parts of comonomer, 15-20 parts of octenyl succinate starch, 20-25 parts of antibacterial filler, 0.16-0.22 parts of lubricant and 0.46-0.52 parts of antioxidant; Step S2, blending: placing the comonomer, lubricant, antibacterial filler and antioxidant in a high-speed mixer according to parts by weight, then adding octenyl succinate starch, stirring and mixing for 8-12 minutes to obtain a mixed material; Step S3, granulation: placing the mixture prepared in step S2 in a twin-screw extruder for melt blending, extruding and granulating to obtain blended pellets; Step S4, injection molding: placing the blended pellets obtained in step S3 in an injection molding machine, and injection molding to obtain an antibacterial biodegradable composite material; The comonomer is prepared by firstly undergoing an ester exchange reaction between a functionalized diol, 1,4-butanediol and dimethyl succinate, and then continuing a polycondensation reaction; The functional diol is first obtained by selectively reducing vanillin to obtain a diphenol monomer, which then undergoes a bimolecular nucleophilic substitution reaction with epichlorohydrin to obtain an epoxy monomer, which is then obtained by a ring-opening esterification reaction with octenylsuccinic anhydride; The antibacterial filler is prepared by hydrolyzing tetrabutyl titanate and coating nano zinc oxide to obtain core-shell particles, which are then modified with KH-560 and finally reacted with o-hydroxybenzoic acid through a ring-opening esterification reaction.

2. The antibacterial biodegradable composite material according to claim 1, characterized in that: The comonomer is prepared by the following steps: Under nitrogen protection, the functionalized diol, 1,4-butanediol and dimethyl succinate are evenly mixed, zinc acetate is added, the temperature is raised to 166-178° C., the reaction is stirred for 6-8 hours, the temperature is then raised to 216-220° C., tetrabutyl titanate is added, the pressure is adjusted to 30-50 Pa, and the polycondensation reaction is carried out for 0.5-0.8 hours to obtain a comonomer, wherein the mass ratio of the functionalized diol, 1,4-butanediol, dimethyl succinate, zinc acetate and tetrabutyl titanate is 3-5:8-12:5.5-8.5:0.04-0.06:0.006-0.

01.

3. The antibacterial degradable composite material according to claim 2, characterized in that: The functionalized diol is prepared by the following steps: Step A1: Vanillin was dissolved in anhydrous THF, and deionized water was added. Under nitrogen protection, sodium percarbonate was added in three equal batches while stirring. The mixture was stirred at room temperature for 2.6-3.2 hours. After the reaction, the pH was adjusted to 3, and the mixture was rotary evaporated, extracted, washed, and dried to obtain a diphenol monomer. Step A2: Add diphenol monomer and tetrabutylammonium bromide to anhydrous DMF, raise the temperature to 45-55° C., stir evenly, and add epichlorohydrin dropwise while stirring. The dripping is controlled to be completed within 15 minutes. After the dripping is completed, raise the temperature to 86-94° C. and continue stirring to react for 6-8 hours. After the reaction is completed, filter under reduced pressure, wash, and dry to obtain an epoxy monomer; Step A3: Add epoxy monomer, octenylsuccinic anhydride and p-toluenesulfonic acid to anhydrous DMF, heat to 76-84° C., stir and react for 3-4 hours. After the reaction is completed, wash, rotary evaporate and dry to obtain functionalized diol.

4. The antibacterial degradable composite material according to claim 3, characterized in that: In step A1, the mass ratio of vanillin, anhydrous THF, deionized water and the total amount of sodium percarbonate is 3-5:100-120:26-30:7.5-12.

5.

5. The antibacterial degradable composite material according to claim 3, characterized in that: In the step A2, the mass ratio of the diphenol monomer, tetrabutylammonium bromide, anhydrous DMF and epichlorohydrin is 2.4-4.2:0.02-0.04:70-80:1.6-2.

6.

6. The antibacterial degradable composite material according to claim 3, characterized in that: In step A3, the mass ratio of epoxy monomer, octenylsuccinic anhydride, p-toluenesulfonic acid and anhydrous DMF is 2-3.6:1.42-2.68:0.012-0.028:60-80.

7. The antibacterial biodegradable composite material according to claim 1, characterized in that: The antibacterial filler is prepared by the following steps: Step B1, drying the nano zinc oxide, then placing it in deionized water, adjusting the pH to 10-11, heating to 50-60°C, ultrasonically dispersing it evenly, adding a mixture of tetrabutyl titanate, urea and deionized water dropwise, and controlling the dripping to be completed within 20 minutes. After the dripping is completed, stirring and reacting for 18-22 minutes, adding a sodium hydroxide aqueous solution, and stirring and reacting for 1.2-1.6 hours at this temperature. After the reaction is completed, filtering, washing, and drying to obtain core-shell particles; Step B2, ultrasonically mix the core-shell particles, deionized water, anhydrous ethanol and KH-560 for 18-24 minutes, heat to 46-52 ° C, stir and react for 6-8 hours, centrifuge, wash and dry the precipitate to obtain epoxy core-shell particles, ultrasonically disperse the epoxy core-shell particles and anhydrous DMF, add tetrabutylammonium bromide, o-hydroxybenzoic acid and anhydrous DMF mixture b dropwise, control the addition within 15 minutes, and after the addition is completed, heat to 86-92 ° C, stir for 5-6 hours, centrifuge, and wash and dry the precipitate to obtain an antibacterial filler.

8. The antibacterial degradable composite material according to claim 7, characterized in that: In step B1, the mass ratio of nano zinc oxide, deionized water, mixed solution a and sodium hydroxide aqueous solution is 3-5:40-50:24-30:10-14, the mass ratio of tetrabutyl titanate, urea and deionized water in the mixed solution a is 14-18:2:65-75, and the concentration of the sodium hydroxide aqueous solution is 2-3M.

9. The antibacterial biodegradable composite material according to claim 7, characterized in that: In step B2, the mass ratio of the core-shell particles, deionized water, anhydrous ethanol and KH-560 is 2.8-3.6:20:46-52:2.4-2.8, the mass ratio of the epoxy core-shell particles, anhydrous DMF and the mixed solution b is 2-3:40-46:24, and in the mixed solution b, the mass ratio of tetrabutylammonium bromide, o-hydroxybenzoic acid and anhydrous DMF is 0.6:1.8-2.2:22-26.

10. Use of the antibacterial and degradable composite material according to any one of claims 1 to 9 in a fresh-keeping box.

Images