阅读说明：本技术 一种长效抗菌防霉pp/ps塑料及其制备方法 (Long-acting antibacterial mildew-proof PP/PS plastic and preparation method thereof ) 是由 伍明电 于 2020-11-03 设计创作，主要内容包括：本发明提出了一种长效抗菌防霉PP/PS塑料,由以下原料制备而成：PP母粒、PS母粒、抗菌防霉剂、微晶纤维素、增塑剂、增韧剂、抗氧剂、紫外线吸收剂；所述抗菌防霉剂中含有2-5wt％的氧化石墨烯/银纳米复合物和3-7wt％的纳他霉素。本发明在PP/PS塑料中同时加入负载了氧化石墨烯/银纳米复合物和纳他霉素的微珠和负载量氧化石墨烯/TiO2纳米复合物和纳他霉素的微珠,两种微珠分别通过银离子抗菌和二氧化钛光催化抑菌的机理提高塑料的抗菌防霉性能,制得的微珠以PP/PS为主体,与本发明塑料的基材一致,从而提高了微珠与基体的相容性,从而不会抗菌防霉剂的添加不会影响塑料的力学性能,具有较好的应用前景。(The invention provides a long-acting antibacterial mildew-proof PP/PS plastic which is prepared from the following raw materials: PP master batch, PS master batch, antibacterial mildew preventive, microcrystalline cellulose, plasticizer, toughening agent, antioxidant and ultraviolet absorbent; the antibacterial mildew preventive contains 2-5 wt% of graphene oxide/silver nano composite and 3-7 wt% of natamycin. According to the invention, the microbeads loaded with the graphene oxide/silver nano compound and the natamycin and the microbeads loaded with the graphene oxide/TiO 2 nano compound and the natamycin are simultaneously added into the PP/PS plastic, the antibacterial and mildew-proof performances of the plastic are respectively improved by the two microbeads through the mechanisms of silver ion antibacterial and titanium dioxide photocatalytic antibacterial, the prepared microbeads take the PP/PS as a main body and are consistent with the base material of the plastic, so that the compatibility of the microbeads and the matrix is improved, the mechanical properties of the plastic cannot be influenced by the addition of the antibacterial and mildew-proof agent, and the application prospect is good.)

1. The long-acting antibacterial mildew-proof PP/PS plastic is characterized by being prepared from the following raw materials: PP master batch, PS master batch, antibacterial mildew preventive, microcrystalline cellulose, plasticizer, toughening agent, antioxidant and ultraviolet absorbent;

the antibacterial mildew preventive contains 2-5 wt% of graphene oxide/silver nano composite and 3-7 wt% of natamycin.

2. The long-acting antibacterial and mildewproof PP/PS plastic is characterized by being prepared from the following raw materials in parts by weight: 200 parts of PP master batch, 250 parts of PS master batch, 5-15 parts of antibacterial mildew preventive, 5-10 parts of microcrystalline cellulose, 1-5 parts of plasticizer, 1-5 parts of toughening agent, 1-5 parts of antioxidant and 1-3 parts of ultraviolet absorbent.

3. The long-acting antibacterial and mildewproof PP/PS plastic according to claim 1, wherein the plasticizer is one or a mixture of two or more of di (2-ethylhexyl) phthalate, dioctyl phthalate, di-n-octyl phthalate, butyl benzyl phthalate, di-sec-octyl phthalate, dicyclohexyl phthalate, dibutyl phthalate and diisobutyl phthalate; the toughening agent is selected from one or more of ethylene propylene rubber, polybutadiene rubber, styrene-butadiene thermoplastic elastomer, acrylonitrile-butadiene-styrene copolymer, chlorinated polyethylene and ethylene-vinyl acetate copolymer; the antioxidant is selected from one or more of 2, 6-tertiary butyl-4-methylphenol, bis (3, 5-tertiary butyl-4-hydroxyphenyl) thioether, tetra [ beta- (3, 5-tertiary butyl-4-hydroxyphenyl) propionic acid ] pentaerythritol ester, didodecyl alcohol ester, ditetradecyl alcohol ester and dioctadecyl alcohol ester, trioctyl ester, tridecyl ester, tridodecyl alcohol ester and trihexadecyl alcohol ester; the ultraviolet absorbent is one or a mixture of more of 2, 2 '-thiobis (4-tert-octylphenoloxy) nickel, tris (1, 2, 2, 6, 6-pentamethylpiperidinyl) phosphite, 4-benzoyloxy-2, 2, 6, 6-tetramethylpiperidine, 2, 4, 6-tris (2' n-butoxyphenyl) -1, 3, 5-triazine and hexamethylphosphoric triamide.

4. The long-acting antibacterial and mildewproof PP/PS plastic is prepared by the following method according to claim 1:

s1, dissolving a dispersing agent in tetrahydrofuran, introducing nitrogen, adding styrene and propylene monomers until the absorption of the tetrahydrofuran on the propylene is saturated, adding an initiator, heating to 50-70 ℃, reacting for 2-5h, and filtering to obtain PP/PS microbeads;

s2, uniformly dispersing the PP/PS microbeads in tetrahydrofuran, swelling for 2-5h, adding monochlorodimethyl ether and a catalyst, reacting for 1-3h at 70-90 ℃, adding ethylene glycol for treating for 0.5-1h, and filtering to obtain porous microbeads;

s3, preparing graphene oxide by adopting a Hummers method;

s4, adding graphene oxide into deionized water, carrying out ultrasonic treatment for 0.5-1h to obtain a uniform graphene oxide-water dispersion, adding silver nitrate, glucose and ammonia water in a dark place, carrying out vigorous stirring reaction for 1-2h, filtering, and repeatedly washing with deionized water to obtain a graphene oxide/silver nano composite;

s5, adding the porous microspheres into an aqueous solution containing 2.5-5 wt% of silane coupling agent, heating to 70-90 ℃ for reaction for 0.5-1h, filtering to obtain surface modified microspheres, adding the surface modified microspheres into deionized water, adding graphene oxide/silver nano composite and natamycin, heating to 50-70 ℃, stirring for reaction for 1-3h, and filtering to obtain the antibacterial and mildewproof agent.

5. The long-acting antibacterial and mildewproof PP/PS plastic as claimed in claim 1, wherein the antibacterial and mildewproof agent contains 2-5 wt% of graphene oxide/TiO₂The nano-composite and 3-7 wt% of natamycin.

6. The long-acting antibacterial and mildewproof PP/PS plastic according to claim 5, wherein the antibacterial and mildewproof agent is prepared by the following method:

s1, dissolving a dispersing agent in tetrahydrofuran, introducing nitrogen, adding styrene and propylene monomers until the absorption of the tetrahydrofuran on the propylene is saturated, adding an initiator, heating to 50-70 ℃, reacting for 2-5h, and filtering to obtain PP/PS microbeads;

s2, uniformly dispersing the PP/PS microbeads in tetrahydrofuran, swelling for 2-5h, adding monochlorodimethyl ether and a catalyst, reacting for 1-3h at 70-90 ℃, adding ethylene glycol for treating for 0.5-1h, and filtering to obtain porous microbeads;

s3, preparing graphene oxide by adopting a Hummers method;

s4, adding graphene oxide into deionized water, carrying out ultrasonic treatment for 0.5-1h to obtain uniform graphene oxide-water dispersion, adding tetrabutyl titanate in a dark place, carrying out violent stirring reaction for 1-2h, filtering, and repeatedly washing with deionized water to obtain graphene oxide/TiO₂A nanocomposite;

s5, adding the porous microspheres into an aqueous solution containing 2.5-5 wt% of silane coupling agent, heating to 70-90 ℃, reacting for 0.5-1h, filtering to obtain surface modified microspheres, adding the surface modified microspheres into deionized water, and adding graphene oxide/TiO₂Heating the nano compound and natamycin to 50-70 ℃, stirring and reacting for 1-3h, and filtering to obtain the antibacterial mildew preventive.

7. The long-acting antibacterial and mildewproof PP/PS plastic as claimed in claim 4 or 6, wherein the dispersing agent is one or a mixture of polyethylene glycol 200, polyethylene glycol 400, polyethylene wax and polyvinyl alcohol; the initiator is selected from one or a mixture of more of potassium persulfate, sodium persulfate, ammonium persulfate, benzoyl peroxide, lauroyl peroxide, cumene hydroperoxide, tert-butyl hydroperoxide, di-tert-butyl peroxide, dicumyl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxypivalate, methyl ethyl ketone peroxide, cyclohexanone peroxide, diisopropyl peroxydicarbonate and dicyclohexyl peroxydicarbonate; the catalyst is selected from one or a mixture of more of anhydrous zinc chloride, stannic chloride, ferric trichloride and aluminum trichloride; the silane coupling agent is selected from one or a mixture of KH550, KH560, KH570, KH580, KH602 and KH 792.

8. The long-acting antibacterial and mildewproof PP/PS plastic as claimed in claim 4, wherein the mass ratio of the dispersant, the styrene, the propylene and the initiator is 1: (100) 200: 70-150: 0.5-0.7); the mass ratio of the PP/PS microbeads to the monochlorodimethyl ether to the catalyst to the ethylene glycol is 100: (35-55): (1-1.2): (5-10); the mass ratio of the graphene oxide to the silver nitrate to the glucose to the ammonia water is 10: (2-5): (5-12): (10-20); the mass ratio of the surface modified microbeads to the graphene oxide/silver nano composite to the natamycin is 100: (4-7): (5-10).

9. The long-acting antibacterial and mildewproof PP/PS plastic as claimed in claim 6, wherein the mass ratio of the dispersant, the styrene, the propylene and the initiator is 1: (100) 200: 70-150: 0.5-0.7); the mass ratio of the PP/PS microbeads to the monochlorodimethyl ether to the catalyst to the ethylene glycol is 100: (35-55): (1-1.2): (5-10); the mass ratio of the graphene oxide to the tetrabutyl titanate is 10: (2-5); the surface modified micro-bead and the graphene oxide/TiO₂The mass ratio of the nano-composite to the natamycin is 100: (4-7): (5-10).

10. A method for preparing the long-acting antibacterial mildew-proof PP/PS plastic as claimed in any one of claims 1-9, comprising the following steps:

s1, adding PP master batches, PS master batches, an antibacterial mildew preventive, microcrystalline cellulose, a plasticizer, a toughening agent, an antioxidant and an ultraviolet absorbent into a double-screw extruder according to a ratio, and mixing and extruding;

s2, conveying the material extruded in the step S1 to a single-screw extruder for extrusion granulation, so as to obtain the long-acting antibacterial mildew-proof PP/PS plastic; the four temperature sections in the mixing and extruding process are as follows: the feeding section 110-.

Technical Field

The invention relates to the technical field of plastics, in particular to a long-acting antibacterial mildew-proof PP/PS plastic and a preparation method thereof.

Background

With the progress of human society, plastic products are more and more important in daily life. Meanwhile, various environmental pollutions are increasingly serious, and plastic products are easily polluted by bacteria in the long-term use process, so that the spreading and spreading of harmful bacteria are directly caused, and the health of people is harmed.

The antibacterial plastic is characterized in that an antibacterial agent is added into the plastic, so that the plastic has antibacterial property, bacteria stained on the plastic can be killed or inhibited within a certain time, and compared with the conventional chemical and physical methods, the antibacterial plastic has long sterilization time, and is economical and convenient. The antibacterial agent is used as an additive and can effectively inhibit the breeding of bacteria. Plastic antibacterial agents are generally classified into inorganic antibacterial agents, organic antibacterial agents, natural antibacterial agents and complex antibacterial agents. Because different antibacterial agents have different antibacterial action mechanisms and effectiveness on the same pathogenic bacteria and different antibacterial action mechanisms and inhibition ranges of the same antibacterial agent on different pathogenic bacteria, the research on the antibacterial agent which is long-acting, broad-spectrum, high-efficiency and safe is needed, and the research on the antibacterial mechanism is very important. However, most of the antibacterial agents added into plastics at present have unobvious antibacterial effect and poor compatibility with plastics, so that the mechanical property of the plastics is remarkably reduced, and the light transmittance of the plastics is influenced due to poor transparency.

Disclosure of Invention

The invention aims to provide a long-acting antibacterial mildew-proof PP/PS plastic and a preparation method thereof, wherein microbeads loaded with a graphene oxide/silver nano compound and a natamycin and microbeads loaded with a graphene oxide/TiO 2 nano compound and a natamycin are simultaneously added into the PP/PS plastic, the antibacterial mildew-proof performance of the plastic is improved by the two microbeads through mechanisms of silver ion antibacterial and titanium dioxide photocatalytic bacteriostasis respectively, and the prepared microbeads take PP/PS as a main body and are consistent with the base material of the plastic, so that the compatibility of the microbeads and the base body is improved, the mechanical property of the plastic cannot be influenced by the addition of the antibacterial mildew-proof agent, and the PP/PS plastic has a good application prospect.

The technical scheme of the invention is realized as follows:

the invention provides a long-acting antibacterial mildew-proof PP/PS plastic which is prepared from the following raw materials: PP master batch, PS master batch, antibacterial mildew preventive, microcrystalline cellulose, plasticizer, toughening agent, antioxidant and ultraviolet absorbent;

the antibacterial mildew preventive contains 2-5 wt% of graphene oxide/silver nano composite and 3-7 wt% of natamycin.

As a further improvement of the invention, the health-care food is prepared from the following raw materials in parts by weight: 200 parts of PP master batch, 250 parts of PS master batch, 5-15 parts of antibacterial mildew preventive, 5-10 parts of microcrystalline cellulose, 1-5 parts of plasticizer, 1-5 parts of toughening agent, 1-5 parts of antioxidant and 1-3 parts of ultraviolet absorbent.

As a further improvement of the invention, the plasticizer is selected from one or a mixture of more of di (2-ethylhexyl) phthalate, dioctyl phthalate, di-n-octyl phthalate, butyl benzyl phthalate, di-sec-octyl phthalate, dicyclohexyl phthalate, dibutyl phthalate and diisobutyl phthalate; the toughening agent is selected from one or more of ethylene propylene rubber, polybutadiene rubber, styrene-butadiene thermoplastic elastomer, acrylonitrile-butadiene-styrene copolymer, chlorinated polyethylene and ethylene-vinyl acetate copolymer; the antioxidant is selected from one or more of 2, 6-tertiary butyl-4-methylphenol, bis (3, 5-tertiary butyl-4-hydroxyphenyl) thioether, tetra [ beta- (3, 5-tertiary butyl-4-hydroxyphenyl) propionic acid ] pentaerythritol ester, didodecyl alcohol ester, ditetradecyl alcohol ester and dioctadecyl alcohol ester, trioctyl ester, tridecyl ester, tridodecyl alcohol ester and trihexadecyl alcohol ester; the ultraviolet absorbent is one or a mixture of more of 2, 2 '-thiobis (4-tert-octylphenoloxy) nickel, tris (1, 2, 2, 6, 6-pentamethylpiperidinyl) phosphite, 4-benzoyloxy-2, 2, 6, 6-tetramethylpiperidine, 2, 4, 6-tris (2' n-butoxyphenyl) -1, 3, 5-triazine and hexamethylphosphoric triamide.

As a further improvement of the invention, the antibacterial mildew preventive is prepared by the following method:

s1, dissolving a dispersing agent in tetrahydrofuran, introducing nitrogen, adding styrene and propylene monomers until the absorption of the tetrahydrofuran on the propylene is saturated, adding an initiator, heating to 50-70 ℃, reacting for 2-5h, and filtering to obtain PP/PS microbeads;

s2, uniformly dispersing the PP/PS microbeads in tetrahydrofuran, swelling for 2-5h, adding monochlorodimethyl ether and a catalyst, reacting for 1-3h at 70-90 ℃, adding ethylene glycol for treating for 0.5-1h, and filtering to obtain porous microbeads;

s3, preparing graphene oxide by adopting a Hummers method;

s4, adding graphene oxide into deionized water, carrying out ultrasonic treatment for 0.5-1h to obtain a uniform graphene oxide-water dispersion, adding silver nitrate, glucose and ammonia water in a dark place, carrying out vigorous stirring reaction for 1-2h, filtering, and repeatedly washing with deionized water to obtain a graphene oxide/silver nano composite;

s5, adding the porous microspheres into an aqueous solution containing 2.5-5 wt% of silane coupling agent, heating to 70-90 ℃ for reaction for 0.5-1h, filtering to obtain surface modified microspheres, adding the surface modified microspheres into deionized water, adding graphene oxide/silver nano composite and natamycin, heating to 50-70 ℃, stirring for reaction for 1-3h, and filtering to obtain the antibacterial and mildewproof agent.

As a further improvement of the invention, the antibacterial and mildewproof agent contains 2-5 wt% of graphene oxide/TiO 2 nano-composite and 3-7 wt% of natamycin.

As a further improvement of the invention, the antibacterial mildew preventive is prepared by the following method:

s1, dissolving a dispersing agent in tetrahydrofuran, introducing nitrogen, adding styrene and propylene monomers until the absorption of the tetrahydrofuran on the propylene is saturated, adding an initiator, heating to 50-70 ℃, reacting for 2-5h, and filtering to obtain PP/PS microbeads;

s2, uniformly dispersing the PP/PS microbeads in tetrahydrofuran, swelling for 2-5h, adding monochlorodimethyl ether and a catalyst, reacting for 1-3h at 70-90 ℃, adding ethylene glycol for treating for 0.5-1h, and filtering to obtain porous microbeads;

s3, preparing graphene oxide by adopting a Hummers method;

s4, adding graphene oxide into deionized water, carrying out ultrasonic treatment for 0.5-1h to obtain uniform graphene oxide-water dispersion, adding tetrabutyl titanate in a dark place, carrying out vigorous stirring reaction for 1-2h, filtering, and repeatedly washing with deionized water to obtain a graphene oxide/TiO 2 nano composite;

s5, adding the porous microspheres into an aqueous solution containing 2.5-5 wt% of silane coupling agent, heating to 70-90 ℃ for reaction for 0.5-1h, filtering to obtain surface modified microspheres, adding the surface modified microspheres into deionized water, adding graphene oxide/TiO 2 nano-composite and natamycin, heating to 50-70 ℃, stirring for reaction for 1-3h, and filtering to obtain the antibacterial mildew preventive.

As a further improvement of the invention, the dispersant is selected from one or a mixture of more of polyethylene glycol 200, polyethylene glycol 400, polyethylene wax and polyvinyl alcohol; the initiator is selected from one or a mixture of more of potassium persulfate, sodium persulfate, ammonium persulfate, benzoyl peroxide, lauroyl peroxide, cumene hydroperoxide, tert-butyl hydroperoxide, di-tert-butyl peroxide, dicumyl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxypivalate, methyl ethyl ketone peroxide, cyclohexanone peroxide, diisopropyl peroxydicarbonate and dicyclohexyl peroxydicarbonate; the catalyst is selected from one or a mixture of more of anhydrous zinc chloride, stannic chloride, ferric trichloride and aluminum trichloride; the silane coupling agent is selected from one or a mixture of KH550, KH560, KH570, KH580, KH602 and KH 792.

As a further improvement of the invention, the mass ratio of the dispersant, the styrene, the propylene and the initiator is 1: (100) 200: 70-150: 0.5-0.7); the mass ratio of the PP/PS microbeads to the monochlorodimethyl ether to the catalyst to the ethylene glycol is 100: (35-55): (1-1.2): (5-10); the mass ratio of the graphene oxide to the silver nitrate to the glucose to the ammonia water is 10: (2-5): (5-12): (10-20); the mass ratio of the surface modified microbeads to the graphene oxide/silver nano composite to the natamycin is 100: (4-7): (5-10).

As a further improvement of the invention, the mass ratio of the dispersant, the styrene, the propylene and the initiator is 1: (100) 200: 70-150: 0.5-0.7); the mass ratio of the PP/PS microbeads to the monochlorodimethyl ether to the catalyst to the ethylene glycol is 100: (35-55): (1-1.2): (5-10); the mass ratio of the graphene oxide to the tetrabutyl titanate is 10: (2-5); the mass ratio of the surface modified microbeads to the graphene oxide/TiO 2 nano composite to the natamycin is 100: (4-7): (5-10).

The invention further provides a preparation method of the long-acting antibacterial mildew-proof PP/PS plastic, which comprises the following steps:

s1, adding PP master batches, PS master batches, an antibacterial mildew preventive, microcrystalline cellulose, a plasticizer, a toughening agent, an antioxidant and an ultraviolet absorbent into a double-screw extruder according to a ratio, and mixing and extruding;

s2, conveying the material extruded in the step S1 to a single-screw extruder for extrusion granulation, so as to obtain the long-acting antibacterial mildew-proof PP/PS plastic.

The four temperature sections in the mixing and extruding process are as follows: the feeding section 110-.

The invention has the following beneficial effects: the invention has prepared a kind of antibacterial mildew preventive, regard PP/PS material as the main material of the microballoons, through the additional cross-linking reaction, send the reaction of the high cross-linking degree with chloromethylation reagent monochlorodimethyl ether on the benzene ring of styrene, form methylene bridge, thus get the microballoons of the high specific surface area, further through the function of the pore-forming agent ethanediol, make the porous microballoons of the high specific surface area originally have more deeper pore canals, further improve its specific surface area;

on the other hand, the invention bonds on the surface of graphene oxide through silver mirror reaction to form a nano-composite, and the nano-composite and the natamycin are coupled in the pore channel of the porous microbead together under the action of a silane coupling agent, so that the antibacterial agent graphene oxide/silver nano-composite and the mildew preventive natamycin are efficiently loaded, the natamycin is a natural mildew preventive, the action mechanism of the natamycin is to combine with ergosterol and other sterol groups of fungi to inhibit the biosynthesis of the ergosterol, so that the cell membrane is distorted, and finally the leakage is caused to cause cell death, and after the two are compounded, most of bacteria, fungi and the like can be killed or inhibited from increasing value, so that the efficient antibacterial effect is achieved, and the composite has better toughening performance;

according to another scheme of the invention, tetrabutyl titanate is hydrolyzed by a sol-gel method to obtain titanium dioxide, the titanium dioxide is bonded on the surface of graphene oxide to form a nano composite, the nano composite and natamycin are coupled in a pore channel of porous microbeads under the action of a silane coupling agent, so that the antibacterial mildew preventive graphene oxide/TiO 2 nano composite and the natamycin are efficiently loaded, and the nano composite of titanium dioxide effectively inhibits bacterial growth and prevents growth of mildew through photocatalysis;

according to the other method, microbeads loaded with the graphene oxide/silver nano compound and the natamycin and microbeads loaded with the graphene oxide/TiO 2 nano compound and the natamycin are added into the PP/PS plastic at the same time, and the antibacterial and mildew-proof performances of the plastic are improved by the two microbeads through mechanisms of silver ion antibacterial and titanium dioxide photocatalytic antibacterial respectively;

the prepared micro-bead takes PP/PS as a main body, is consistent with the base material of the plastic, so that the compatibility of the micro-bead and the base body is improved, the mechanical property of the plastic cannot be influenced by the addition of the antibacterial mildew preventive, and the micro-bead has a better application prospect.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Preparation example 1 antibacterial and antifungal agent

The preparation method comprises the following steps:

s1, dissolving 1g of dispersant polyethylene glycol 400 in 200mL of tetrahydrofuran, introducing nitrogen, adding 100g of styrene and 70g of propylene monomers until the propylene absorption of the tetrahydrofuran is saturated, adding 0.5g of initiator potassium persulfate, heating to 50 ℃, reacting for 2 hours, and filtering to obtain PP/PS microbeads;

s2, uniformly dispersing 100g of PP/PS microbeads in 200mL of tetrahydrofuran, swelling for 2h, adding 35g of chlorodimethyl ether and 1g of catalyst tin chloride, reacting for 1h at 70 ℃, adding 5g of glycol, treating for 0.5h, and filtering to obtain porous microbeads;

s3, preparing graphene oxide by adopting a Hummers method;

s4, adding 10g of graphene oxide into 50mL of deionized water, carrying out ultrasonic treatment for 0.5h to obtain a uniform graphene oxide-water dispersion solution, adding 2g of silver nitrate, 5g of glucose and 10g of ammonia water in a dark place, carrying out vigorous stirring reaction for 1h, filtering, and repeatedly washing with deionized water to obtain a graphene oxide/silver nano compound;

s5, adding 100g of porous microbeads into 200mL of aqueous solution containing 2.5 wt% of silane coupling agent KH550, heating to 70 ℃, reacting for 0.5h, filtering to obtain surface modified microbeads, adding the surface modified microbeads into deionized water, adding 4g of graphene oxide/silver nano-composite and 5g of natamycin, heating to 50 ℃, stirring, reacting for 1h, and filtering to obtain the antibacterial mildew preventive, wherein the antibacterial mildew preventive contains 2 wt% of graphene oxide/silver nano-composite and 3 wt% of natamycin.

Preparation example 2 antibacterial and antifungal agent

The preparation method comprises the following steps:

s1, dissolving 1g of dispersant polyethylene glycol 200 in 200mL of tetrahydrofuran, introducing nitrogen, adding 200g of styrene and 150g of propylene monomers until the propylene absorption by the tetrahydrofuran is saturated, adding 0.7g of initiator cumene hydroperoxide, heating to 70 ℃, reacting for 5 hours, and filtering to obtain PP/PS microbeads;

s2, uniformly dispersing 100g of PP/PS microbeads in 200mL of tetrahydrofuran, swelling for 5h, adding 55g of monochlorodimethyl ether and 1.2g of catalyst ferric trichloride, reacting for 3h at 90 ℃, adding 10g of ethylene glycol, treating for 1h, and filtering to obtain porous microbeads;

s3, preparing graphene oxide by adopting a Hummers method;

s4, adding 10g of graphene oxide into 50mL of deionized water, carrying out ultrasonic treatment for 1h to obtain a uniform graphene oxide-water dispersion, adding 5g of silver nitrate, 12g of glucose and 20g of ammonia water in a dark place, carrying out vigorous stirring reaction for 2h, filtering, and repeatedly washing with deionized water to obtain a graphene oxide/silver nano compound;

s5, adding 100g of porous microbeads into 200mL of aqueous solution containing 5 wt% of silane coupling agent KH560, heating to 90 ℃, reacting for 1h, filtering to obtain surface-modified microbeads, adding the surface-modified microbeads into deionized water, adding 7g of graphene oxide/silver nano-composite and 10g of natamycin, heating to 70 ℃, stirring, reacting for 3h, and filtering to obtain the antibacterial mildew preventive containing 5 wt% of graphene oxide/silver nano-composite and 7 wt% of natamycin.

Comparative example 1

Compared with preparation example 2, natamycin was not added and other conditions were not changed.

S5, adding 100g of porous microbeads into 200mL of aqueous solution containing 5 wt% of silane coupling agent KH560, heating to 90 ℃, reacting for 1h, filtering to obtain surface-modified microbeads, adding the surface-modified microbeads into deionized water, adding 17g of graphene oxide/silver nano-composite, heating to 70 ℃, stirring, reacting for 3h, and filtering to obtain the antibacterial mildew preventive containing 12 wt% of graphene oxide/silver nano-composite.

Comparative example 2

Compared with preparation example 2, the graphene oxide/silver nanocomposite is not added, and other conditions are not changed.

S5, adding 100g of porous microbeads into 200mL of aqueous solution containing 5 wt% of silane coupling agent KH560, heating to 90 ℃, reacting for 1h, filtering to obtain surface-modified microbeads, adding the surface-modified microbeads into deionized water, adding 17g of natamycin, heating to 70 ℃, stirring, reacting for 3h, and filtering to obtain the antibacterial mildew preventive containing 12 t% of natamycin.

Preparation example 3 antibacterial and antifungal agent

The preparation method comprises the following steps:

s1, dissolving 1g of dispersant polyethylene wax in 200mL of tetrahydrofuran, introducing nitrogen, adding 100g of styrene and 70g of propylene monomers until the propylene absorption by the tetrahydrofuran is saturated, adding 0.5g of initiator di-tert-butyl peroxide, heating to 50 ℃, reacting for 2 hours, and filtering to obtain PP/PS microbeads;

s2, uniformly dispersing 100g of PP/PS microbeads in 200mL of tetrahydrofuran, swelling for 2h, adding 35g of monochlorodimethyl ether and 1g of catalyst ferric trichloride, reacting for 1h at 70 ℃, adding 5g of ethylene glycol, treating for 0.5h, and filtering to obtain porous microbeads;

s3, preparing graphene oxide by adopting a Hummers method;

s4, adding 10g of graphene oxide into deionized water, carrying out ultrasonic treatment for 0.5h to obtain uniform graphene oxide-water dispersion, adding 2g of tetrabutyl titanate in a dark place, carrying out vigorous stirring reaction for 1h, filtering, and repeatedly washing with deionized water to obtain a graphene oxide/TiO 2 nano composite;

s5, adding 100g of porous microbeads into 200mL of aqueous solution containing 2.5 wt% of silane coupling agent KH580, heating to 70 ℃, reacting for 0.5h, filtering to obtain surface modified microbeads, adding the surface modified microbeads into deionized water, adding 4g of graphene oxide/TiO 2 nano-composite and 5g of natamycin, heating to 50 ℃, stirring, reacting for 1h, and filtering to obtain the antibacterial mildew preventive, wherein the antibacterial mildew preventive contains 2 wt% of graphene oxide/TiO 2 nano-composite and 3 wt% of natamycin.

Preparation example 4 antibacterial and antifungal agent

The preparation method comprises the following steps:

s1, dissolving 1g of dispersant polyvinyl alcohol in 200mL of tetrahydrofuran, introducing nitrogen, adding 200g of styrene and 150g of propylene monomers until the propylene absorption of the tetrahydrofuran is saturated, adding 0.7g of initiator methyl ethyl ketone peroxide, heating to 70 ℃, reacting for 5 hours, and filtering to obtain PP/PS microbeads;

s2, uniformly dispersing 100g of PP/PS microbeads in 200mL of tetrahydrofuran, swelling for 5h, adding 55g of monochlorodimethyl ether and 1.2g of catalyst aluminum trichloride, reacting for 3h at 90 ℃, adding 10g of ethylene glycol, treating for 1h, and filtering to obtain porous microbeads;

s3, preparing graphene oxide by adopting a Hummers method;

s4, adding 10g of graphene oxide into deionized water, carrying out ultrasonic treatment for 1h to obtain uniform graphene oxide-water dispersion, adding 5g of tetrabutyl titanate in a dark place, carrying out violent stirring reaction for 2h, filtering, and repeatedly washing with deionized water to obtain a graphene oxide/TiO 2 nano composite;

s5, adding 100g of porous microbeads into 200mL of aqueous solution containing 5 wt% of silane coupling agent KH570, heating to 90 ℃, reacting for 1h, filtering to obtain surface-modified microbeads, adding the surface-modified microbeads into deionized water, adding 7g of graphene oxide/TiO 2 nano-composite and 10g of natamycin, heating to 70 ℃, stirring, reacting for 3h, and filtering to obtain the antibacterial mildew preventive containing 5 wt% of graphene oxide/TiO 2 nano-composite and 7 wt% of natamycin.

Comparative example 3

Compared with preparation example 4, natamycin was not added and other conditions were not changed.

S5, adding 100g of porous microbeads into 200mL of aqueous solution containing 5 wt% of silane coupling agent KH570, heating to 90 ℃, reacting for 1h, filtering to obtain surface-modified microbeads, adding the surface-modified microbeads into deionized water, adding 17g of graphene oxide/TiO 2 nano-composite, heating to 70 ℃, stirring, reacting for 3h, and filtering to obtain the antibacterial mildew preventive containing 12 wt% of graphene oxide/TiO 2 nano-composite.

Example 1

The raw materials comprise the following components in parts by weight: 100 parts of PP master batch, 150 parts of PS master batch, 5 parts of antibacterial and mildewproof agent prepared in preparation example 1, 5 parts of microcrystalline cellulose, 1 part of butyl benzyl phthalate, 1 part of polybutadiene rubber, 1 part of tridecyl ester and 1 part of 2, 4, 6-tri (2' n-butoxyphenyl) -1, 3, 5-triazine.

The preparation method comprises the following steps:

s1, adding PP master batches, PS master batches, an antibacterial mildew preventive, microcrystalline cellulose, butyl benzyl phthalate, polybutadiene rubber, tridecyl ester, 2, 4, 6-tris (2' n-butoxyphenyl) -1, 3, 5-triazine into a double-screw extruder according to a ratio, and mixing and extruding;

s2, conveying the material extruded in the step S1 to a single-screw extruder for extrusion granulation, so as to obtain the long-acting antibacterial mildew-proof PP/PS plastic.

The four temperature sections in the mixing extrusion process are as follows: the feeding section is 110 ℃, the conveying section is 125 ℃, the melting section is 135 ℃ and the extrusion section is 140 ℃.

Example 2

The raw materials comprise the following components in parts by weight: 200 parts of PP master batch, 250 parts of PS master batch, 15 parts of the antibacterial and antifungal agent prepared in preparation example 2, 10 parts of microcrystalline cellulose, 5 parts of diisobutyl phthalate, 5 parts of tetra [ beta- (3, 5-tertiary butyl-4-hydroxyphenyl) propionic acid ] pentaerythritol ester and 3 parts of hexamethylphosphoric triamide.

The preparation method comprises the following steps:

s1, adding PP master batches, PS master batches, an antibacterial mildew preventive, microcrystalline cellulose, diisobutyl phthalate, pentaerythritol tetrakis [ beta- (3, 5-tertiary butyl-4-hydroxyphenyl) propionate ] and hexamethylphosphoric triamide into a double-screw extruder according to a ratio for mixing and extruding;

s2, conveying the material extruded in the step S1 to a single-screw extruder for extrusion granulation, so as to obtain the long-acting antibacterial mildew-proof PP/PS plastic.

The four temperature sections in the mixing extrusion process are as follows: the feeding section is 120 ℃, the conveying section is 135 ℃, the melting section is 145 ℃, and the extrusion section is 150 ℃.

Example 3

The raw materials comprise the following components in parts by weight: 150 parts of PP master batch, 200 parts of PS master batch, 10 parts of the antibacterial and mildewproof agent prepared in preparation example 2, 7 parts of microcrystalline cellulose, 3 parts of di (2-ethylhexyl) phthalate, 3 parts of polybutadiene rubber, 3 parts of 2, 6-tertiary butyl-4-methylphenol and 2 parts of tris (1, 2, 2, 6, 6-pentamethylpiperidinyl) phosphite.

The preparation method comprises the following steps:

s1, adding PP (polypropylene) master batches, PS (polystyrene) master batches, an antibacterial mildew preventive, microcrystalline cellulose, di (2-ethylhexyl) phthalate, polybutadiene rubber, 2, 6-tertiary butyl-4-methylphenol and tris (1, 2, 2, 6, 6-pentamethylpiperidinyl) phosphite ester into a double-screw extruder according to a ratio, and mixing and extruding;

s2, conveying the material extruded in the step S1 to a single-screw extruder for extrusion granulation, so as to obtain the long-acting antibacterial mildew-proof PP/PS plastic.

The four temperature sections in the mixing extrusion process are as follows: a feeding section of 115 ℃, a conveying section of 130 ℃, a melting section of 140 ℃ and an extrusion section of 145 ℃.

Example 4

Compared with the example 3, the antibacterial and mildewproof agent is prepared from the preparation example 4, and other conditions are not changed.

Example 5

Compared with the embodiment 3, the antibacterial and mildewproof agent is prepared by mixing the antibacterial and mildewproof agents prepared in the preparation examples 2 and 4 according to the ratio of 1:1, and other conditions are not changed.

Comparative example 4

Compared with example 3, the antibacterial and antifungal agent is prepared from comparative example 1, and other conditions are not changed.

Comparative example 5

Compared with example 3, the antibacterial and antifungal agent is prepared from comparative example 2, and other conditions are not changed.

Comparative example 6

Compared with example 3, the antibacterial and antifungal agent is prepared from comparative example 3, and other conditions are not changed.

Test example 1 antibacterial and mildewproof property test

Test objects: the long-acting antibacterial mildew-proof PP/PS plastics prepared in the examples 1-5 and the comparative examples 4-6 and the commercial antibacterial mildew-proof PP/PS plastics.

And (3) drying the long-acting antibacterial mildew-proof PP/PS plastic in a constant-temperature oven at 95 ℃ for 5 hours, heating and injecting into a plastic sample with the thickness of 50mm multiplied by 50mm, and performing an antibacterial test.

Antibacterial activity against Escherichia coli and Staphylococcus aureus

Testing is carried out according to a test method 1 pasting method of standard GB21551.2-2010, and bacteria for detection: escherichia coli; staphylococcus aureus bacteria; candida albicans; each example and comparative example was tested in parallel for 5 and averaged. The results are shown in Table 1.

TABLE 1

1. Inhibition rate to mould

The test was carried out according to the test method of Standard QB/T2591 (2003) with the following bacteria: aspergillus niger, Aspergillus terreus, Chaetomium globosum, 5 per example and comparative example were tested in parallel and averaged. The results are shown in Table 2.

TABLE 2

Group of	Aspergillus niger mould growth grade	Aspergillus terreus growth grade	Glomus coccineus mildew grade
				Example 1	Level 1	Level 0	Level 0
Example 2	Level 0	Level 0	Level 1
				Example 3	Level 0	Level 0	Level 0
Example 4	Level 0	Level 0	Level 0
				Example 5	Level 0	Level 0	Level 0
Comparative example 4	Stage 2	Level 1	Stage 2
				Comparative example 5	Level 1	Level 0	Level 1
Comparative example 6	Stage 2	Level 1	Level 1
				Is commercially available	Stage 2	Stage 2	Stage 2

Test example 2 mechanical Property test

Test objects: the long-acting antibacterial mildew-proof PP/PS plastics prepared in the examples 1-5 and the comparative examples 4-6 and the commercial antibacterial mildew-proof PP/PS plastics.

The tensile strength is detected according to the method GB/T1040.1-2018;

the bending property is detected according to the GB/T9341-2008 method;

the impact strength is detected according to a GB/T1843 method;

the results are shown in Table 3.

TABLE 3

Test example 3 aging resistance test

Test objects: the long-acting antibacterial mildew-proof PP/PS plastics prepared in the examples 1-5 and the comparative examples 4-6 and the commercial antibacterial mildew-proof PP/PS plastics.

The products obtained in the above examples and comparative examples were subjected to a performance test after artificially accelerated aging under conditions of (90 ℃, 500 hours); the results are shown in Table 4.

TABLE 4

Test example 4 high temperature resistance test

Test objects: the long-acting antibacterial mildew-proof PP/PS plastics prepared in the examples 1-5 and the comparative examples 4-6 and the commercial antibacterial mildew-proof PP/PS plastics.

The heat distortion temperature was carried out in accordance with ISO75, the specimen dimensions were 120 mm. times.10 mm. times.3 mm, the load was 1.8MPa, and the results are shown in Table 5.

TABLE 5

As can be seen from the table, the antibacterial plastic prepared by the embodiment of the invention has good mechanical property, ageing resistance and high temperature resistance.

Comparative example 4, comparative example 5, comparative example 6 compared with example 3, respectively using the antibacterial and antifungal agents prepared in comparative examples 1, 2, 3, in comparative examples 1, 2, 3 only adding graphene oxide/silver nanocomposite, natamycin, graphene oxide/TiO 2 nanocomposite, its antibacterial and antifungal effects are significantly reduced, comparative examples 4, 6 antibacterial better, comparative example 5 antifungal, natamycin is a natural antifungal agent, its mechanism of action is to combine with ergosterol and other sterol groups of fungi, inhibiting ergosterol biosynthesis, thus making cell membrane distortion, finally causing leakage, causing cell death, after the two are compounded, can kill or inhibit proliferation of most bacteria, fungi, etc., thus achieving high-efficiency antibacterial effect, the titanium dioxide nano-scale composite has photocatalytic performance, effectively inhibiting the breeding of bacteria and preventing the growth of mould, and the silver nano compound can dissipate silver ions, thereby efficiently inhibiting the breeding of bacteria; on the other hand, the aging resistance and mechanical property of the comparative example 5 are superior to those of the comparative examples 4 and 6, and it can be seen that the addition of natamycin also has the characteristics of toughening, improving mechanical property and aging resistance to a certain extent.

Example 5 compared with comparative example 3, the antibacterial and antifungal agents prepared in preparation examples 2 and 4 are added, the effect is the best, and the addition of the two antibacterial and antifungal agents has a synergistic effect.

Compared with the prior art, the antibacterial mildew preventive is prepared by taking a PP/PS material as a main material of microspheres, and through an additional crosslinking reaction, sending a reaction with high crosslinking degree with chloromethylation reagent monochlorodimethyl ether on a benzene ring of styrene to form a methylene bridge, so that microbeads with high specific surface area are obtained, and further through the action of a pore-forming agent glycol, the porous microbeads with high specific surface area originally have more and deeper pore channels, so that the specific surface area of the microspheres is further improved;

on the other hand, the invention bonds on the surface of graphene oxide through silver mirror reaction to form a nano-composite, and the nano-composite and the natamycin are coupled in the pore channel of the porous microbead together under the action of a silane coupling agent, so that the antibacterial agent graphene oxide/silver nano-composite and the mildew preventive natamycin are efficiently loaded, the natamycin is a natural mildew preventive, the action mechanism of the natamycin is to combine with ergosterol and other sterol groups of fungi to inhibit the biosynthesis of the ergosterol, so that the cell membrane is distorted, and finally the leakage is caused to cause cell death, and after the two are compounded, most of bacteria, fungi and the like can be killed or inhibited from increasing value, so that the efficient antibacterial effect is achieved, and the composite has better toughening performance;

according to another scheme of the invention, tetrabutyl titanate is hydrolyzed by a sol-gel method to obtain titanium dioxide, the titanium dioxide is bonded on the surface of graphene oxide to form a nano composite, the nano composite and natamycin are coupled in a pore channel of porous microbeads under the action of a silane coupling agent, so that the antibacterial mildew preventive graphene oxide/TiO 2 nano composite and the natamycin are efficiently loaded, and the nano composite of titanium dioxide effectively inhibits bacterial growth and prevents growth of mildew through photocatalysis;

according to the other method, microbeads loaded with the graphene oxide/silver nano compound and the natamycin and microbeads loaded with the graphene oxide/TiO 2 nano compound and the natamycin are added into the PP/PS plastic at the same time, and the antibacterial and mildew-proof performances of the plastic are improved by the two microbeads through mechanisms of silver ion antibacterial and titanium dioxide photocatalytic antibacterial respectively;

the prepared micro-bead takes PP/PS as a main body, is consistent with the base material of the plastic, so that the compatibility of the micro-bead and the base body is improved, the mechanical property of the plastic cannot be influenced by the addition of the antibacterial mildew preventive, and the micro-bead has a better application prospect.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.