阅读说明：本技术 具有抗菌防霉功能的泡沫塑料 (Foam plastic with antibacterial and mildewproof functions ) 是由 魏旭东 丁向丽 于 2021-07-20 设计创作，主要内容包括：本发明公开了一种具有抗菌防霉功能的泡沫塑料及其制备方法,采用一步法制备泡沫塑料,工艺简单耗能低步骤少；所得具有抗菌防霉功能的泡沫塑料具有细密均匀的优质泡孔,机械性能好,具备优异且持久稳定的抗菌防霉效果。(The invention discloses a foamed plastic with antibacterial and mildewproof functions and a preparation method thereof, and the foamed plastic is prepared by adopting a one-step method, so that the process is simple, the energy consumption is low, and the steps are few; the obtained foam plastic with the antibacterial and mildewproof functions has fine, dense, uniform and high-quality cells, good mechanical properties and excellent, lasting and stable antibacterial and mildewproof effects.)

1. The preparation method of the foam plastic with the antibacterial and mildewproof functions is characterized by comprising the following steps:

(1) according to the weight portion, 40 to 70 portions of polyol composition and 0.5 to 1.8 portions of composite antibacterial agent are evenly mixed under the conditions of 25 to 30 ℃ and 30 to 60 percent of relative humidity; then adding 50-80 parts of polyisocyanate, stirring at the rotating speed of 400-800rpm for 14-30s, injecting into a mold preheated to 60-90 ℃, and foaming and molding at 60-90 ℃ for 3-10min to obtain molded foam plastic;

(2) and putting the formed foam plastic and the mold into an oven with the temperature of 80-100 ℃ for drying for 2-4h, naturally cooling to room temperature, and taking out the foam plastic after stripping from the mold.

2. The method for preparing foam having antibacterial and antifungal effects as claimed in claim 1, wherein the polyisocyanate is any one of Toluene Diisocyanate (TDI), isophorone diisocyanate (IPDI), diphenylmethane diisocyanate (MDI), dicyclohexylmethane diisocyanate (HMDI), Hexamethylene Diisocyanate (HDI), Lysine Diisocyanate (LDI), and polyphenyl polymethylene polyisocyanate (PAPI).

3. The method for preparing foam having antibacterial and antifungal properties as claimed in claim 1, wherein the polyol composition comprises, in parts by weight: 80-120 parts of polyol, 2-5 parts of plasticizer, 2-8 parts of catalyst, 6-14 parts of foaming agent and 3-6 parts of foam stabilizer.

4. The method for preparing foam having antibacterial and antifungal effects as claimed in claim 3, wherein the polyol is at least one of polyether polyol, polyester polyol and polymer polyol.

5. The method for preparing a foam having antibacterial and antifungal properties as claimed in claim 3, wherein the catalyst is a mixture of an organotin catalyst and a tertiary amine catalyst.

6. The process for preparing foam having antibacterial and antifungal effects as claimed in claim 3, wherein the blowing agent is a mixture of water and pentane hydrocarbon.

7. The method for preparing a foam having antibacterial and antifungal properties as claimed in claim 3, wherein the foam stabilizer is a silicone oil foam stabilizer.

8. The method for preparing the foam plastic with the antibacterial and mildewproof functions as claimed in claim 1, wherein the method for preparing the composite antibacterial agent comprises the following steps:

s1, adding 2-4 parts of nano tin dioxide into 76-88 parts of thin Ti layer with the concentration of 1-8mg/mL according to parts by weight₃C₂T_XIn the water dispersion, ultrasonic dispersion treatment is carried out for 0.5-2h under the conditions of room temperature, 200-400W and 30-40kHz to obtain inorganic composite antibacterial liquid;

s2, adding 1-5 parts of chitosan into the inorganic composite antibacterial liquid, and stirring and reacting at the rotating speed of 100-300rpm for 10-15h at room temperature to obtain an organic-inorganic composite antibacterial liquid;

s3, carrying out vacuum filtration on the organic-inorganic composite antibacterial liquid to obtain a filter cake a, then adding water until the filter cake a is immersed, washing, carrying out suction filtration, washing for 1-3 times to obtain a filter cake b, then adding absolute ethyl alcohol until the filter cake b is immersed, carrying out alcohol washing, carrying out suction filtration, and washing for 1-3 times to obtain a solid substance I, and carrying out vacuum drying on the solid substance I at the temperature of 40-55 ℃ for 8-10 hours to obtain the composite antibacterial agent.

9. The method for preparing the foam plastic with the functions of resisting bacteria and preventing mildew according to claim 8, wherein the method for preparing the composite antibacterial agent comprises the following steps:

s1, adding 2-4 parts of nano tin dioxide into 76-88 parts of thin Ti layer with the concentration of 1-8mg/mL according to parts by weight₃C₂T_XIn the water dispersion, ultrasonic dispersion treatment is carried out for 0.5-2h under the conditions of room temperature, 200-400W and 30-40kHz to obtain inorganic composite antibacterial liquid;

s2, dropwise adding ammonia water into the inorganic composite antibacterial liquid to adjust the pH value to 8, then adding 0.5-1 part of dopamine, stirring at the rotation speed of 150-350rpm for 8-16min, and standing at room temperature for reaction for 24-36h to obtain dopamine co-modified inorganic composite antibacterial liquid;

s3, adding 1-5 parts of chitosan into the dopamine co-modified inorganic composite antibacterial liquid, and stirring and reacting at the rotating speed of 100-300rpm for 10-15 hours at room temperature to obtain an organic-inorganic composite antibacterial liquid;

s4, carrying out vacuum filtration on the organic-inorganic composite antibacterial liquid to obtain a filter cake a, then adding water until the filter cake a is immersed, washing, carrying out suction filtration, washing for 1-3 times to obtain a filter cake b, then adding absolute ethyl alcohol until the filter cake b is immersed, carrying out alcohol washing, carrying out suction filtration, and washing for 1-3 times to obtain a solid substance I, and carrying out vacuum drying on the solid substance I at the temperature of 40-55 ℃ for 8-10 hours to obtain the composite antibacterial agent.

10. Foam with antibacterial and antifungal properties, prepared by the process according to any of claims 1 to 9.

Technical Field

The invention belongs to the technical field of foamed plastics, and particularly relates to a foamed plastic with antibacterial and mildewproof functions.

Background

The foamed plastic is also called microporous plastic, and is integrally distributed with countless interconnected or non-interconnected micropores so as to obviously reduce the apparent density. The foam is a polymer material containing a large number of cells and having a plastic as a basic component, and therefore can be said to be a composite plastic having a gas as a filler. The foam plastic has a plurality of excellent performances of light weight, heat insulation, sound absorption, shock absorption and the like, is a polymer material formed by dispersing a large number of gas micropores in solid plastic, and has a very wide application range.

Because the foam plastic material contains nutrient substances necessary for bacteria, mold and the like, under the condition of proper temperature and humidity, the bacteria, the mold and other microorganisms can be greatly propagated, the mold secretion causes the biodegradation of the foam plastic, and along with the improvement of the living standard of people, more and more fields put forward higher requirements on the sanitary performance of the material, so that the corresponding requirements on the antibacterial property of the foam plastic are also provided. Commonly used antibacterial agents can be classified into inorganic antibacterial agents, organic antibacterial agents and natural polymeric antibacterial agents. Wherein the inorganic antibacterial agent has strong antibacterial property but poor antibacterial durability; the organic antibacterial agent has rich selectivity and excellent antibacterial effect; the natural polymer antibacterial agent has good biocompatibility, low toxicity and excellent antibacterial property.

Chinese patent CN 110845700A discloses an antibacterial flame-retardant flexible polyurethane foam plastic, which comprises the following components in parts by mass: 50-100 parts of polyether polyol, 10-60 parts of flame-retardant polymer polyol, 20-30 parts of guanidyl maleic hydrochloride, 0.5-2 parts of silicone oil, 1-3 parts of diethanolamine, 80-120 parts of polyisocyanate, 1-2.5 parts of catalyst and 4-10 parts of deionized water, wherein the polyether polyol has an average hydroxyl number of 2-3 and a hydroxyl value of 70-250 mgKOH/g. The antibacterial flame-retardant flexible polyurethane foam plastic disclosed by the invention meets the requirements on physical indexes such as foam density, compression strength, tensile strength and the like, and has antibacterial property. However, guanidino maleic acid hydrochloride is selected as the organic antibacterial agent, the whole dosage of the antibacterial agent is large, the organic antibacterial agent is poor in heat resistance, easy to generate drug resistance, and the decomposition product is toxic and uncertain in safety.

Chinese patent CN 108117762A is a nano titanium dioxide antibacterial plastic and a production process thereof, the nano titanium dioxide antibacterial plastic is prepared from 70-90 parts of epoxy modified resin, 0.2-1 part of plasticizer, 0.2-1.5 parts of foaming agent, 0.5-1 part of vinyl bis stearamide, 0.5-1 part of zinc stearate, 0.1-0.7 part of initiator, 0.2-0.8 part of antioxidant, 0.3-0.8 part of surfactant, 0.3-0.8 part of nano titanium dioxide and 1-2 parts of water, and has an antibacterial effect. The ultrasonic auxiliary surfactant is adopted to treat the nano titanium dioxide, so that a certain effect is achieved on the dispersion of nano particles, but the self-aggregation phenomenon of dispersed nano particles in the subsequent process cannot be inhibited, and the effectiveness of nano components is difficult to ensure.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides the foam plastic with the antibacterial and mildewproof functions.

The preparation method of the foam plastic with the antibacterial and mildewproof functions comprises the following steps:

(1) according to the weight portion, 40 to 70 portions of polyol composition and 0.5 to 1.8 portions of composite antibacterial agent are evenly mixed under the conditions of 25 to 30 ℃ and 30 to 60 percent of relative humidity; then adding 50-80 parts of polyisocyanate, stirring at the rotating speed of 400-800rpm for 14-30s, injecting into a mold preheated to 60-90 ℃, and foaming and molding at 60-90 ℃ for 3-10min to obtain molded foam plastic;

(2) and putting the formed foam plastic and the mold into an oven with the temperature of 80-100 ℃ for drying for 2-4h, naturally cooling to room temperature, and taking out the foam plastic after stripping from the mold.

The polyisocyanate is any one of Toluene Diisocyanate (TDI), isophorone diisocyanate (IPDI), diphenylmethane diisocyanate (MDI), dicyclohexylmethane diisocyanate (HMDI), Hexamethylene Diisocyanate (HDI), Lysine Diisocyanate (LDI) and polyphenyl polymethylene polyisocyanate (PAPI).

The polyol composition comprises the following components in parts by weight: 80-120 parts of polyol, 2-5 parts of plasticizer, 2-8 parts of catalyst, 6-14 parts of foaming agent and 3-6 parts of foam stabilizer.

The polyol is at least one of polyether polyol, polyester polyol and polymer polyol.

Preferably, the polyol is a polyether polyol mixture with a hydroxyl value of 350-650mg KOH/g and a functionality of 2.8-3.6.

The plasticizer is any one of dibutyl phthalate and dioctyl phthalate.

The catalyst is an organic tin catalyst and/or a tertiary amine catalyst.

Preferably, the catalyst is a mixture of an organotin-based catalyst and a tertiary amine-based catalyst.

Further preferably, the catalyst is prepared by mixing an organic tin catalyst and a tertiary amine catalyst in a mass ratio of (1-2.4): 1.

The organic tin catalyst is one of dibutyltin dilaurate and stannous octoate.

The tertiary amine catalyst is one of triethanolamine, triethylene diamine and triethylamine.

Tertiary amine catalyst to isocyano (-NCO)/water (H)₂O) reaction has high catalytic rate, and the organotin catalyst is p-NCO/H₂The O reaction has low catalytic speed, but the p-NCO/-OH reaction has high catalytic speed, and the molecular weight of the product can be rapidly increased, gel is generated, and the viscosity is rapidly increased. The main foaming agent of the invention is a chemical foaming agent H₂And O, when the tertiary amine catalyst is used alone, the generation of gas reduces the viscosity of the system, influences the chain growth rate, and further causes bubble breakage and structure collapse. The organic tin catalyst used alone is easy to cause insufficient body foaming and overlarge system viscosity. The reasonable combination of the foaming agent and the foam stabilizer can simultaneously catalyze the foaming reaction and the chain growth reaction, so that the reaction is rapidly carried out, and the foaming agent and the foam stabilizer are mutually balanced under the combined action of the foaming agent and the foam stabilizer to generate ideal foam. And the composite antibacterial agent can uniformly and stably exist in the foam plastic matrix, and the antibacterial and mildewproof functions are realized.

The foaming agent is water or a mixture of pentane hydrocarbon and water.

Preferably, the foaming agent is a mixture of pentane hydrocarbon and water in a mass ratio of 1: (2.2-4.8).

The pentane hydrocarbon is one of n-pentane, cyclopentane and isopentane.

Isocyanate reacts with water to generate CO₂The foaming gas generates heat, pentane hydrocarbon is easy to gasify at a low boiling point, and the pentane hydrocarbon absorbs reaction heat to generate the foaming gas. When water is used as a foaming agent alone, because reaction heat cannot be rapidly transferred and dissipated, heat overstock causes gas volume to expand too fast, side reaction is easy to generate, and the generated bubbles are large and uneven in pore size and mostly open pores.The proportion of pentane hydrocarbon and water is controlled by compounding, so that isocyanate and water are subjected to chemical reaction to generate CO₂The foaming reaction heat is absorbed by a physical foaming agent pentane hydrocarbon, new foaming gas is generated, and the temperature is reduced at the same time, so that multipoint simultaneous foaming is realized, mutual overstocking is not easy to break, the gas expansion rate is in a controllable range, the generated foam is fine and dense, the proportion of open pores and closed pores is controlled to be appropriate under the condition that a cell opening agent is not used independently, and the mechanical strength of the foamed plastic is improved.

The foam stabilizer is a silicone oil foam stabilizer. Plays the roles of emulsifying foam materials, stabilizing foams and regulating cells.

The preparation method of the composite antibacterial agent comprises the following steps:

s1, adding 2-4 parts of nano tin dioxide into 76-88 parts of thin Ti layer with the concentration of 1-8mg/mL according to parts by weight₃C₂T_XIn the water dispersion, ultrasonic dispersion treatment is carried out for 0.5-2h under the conditions of room temperature, 200-400W and 30-40kHz to obtain inorganic composite antibacterial liquid;

s2, adding 1-5 parts of chitosan into the inorganic composite antibacterial liquid, and stirring and reacting at the rotating speed of 100-300rpm for 10-15h at room temperature to obtain an organic-inorganic composite antibacterial liquid;

s3, carrying out vacuum filtration on the organic-inorganic composite antibacterial liquid to obtain a filter cake a, then adding water until the filter cake a is immersed, washing, carrying out suction filtration, washing for 1-3 times to obtain a filter cake b, then adding absolute ethyl alcohol until the filter cake b is immersed, carrying out alcohol washing, carrying out suction filtration, and washing for 1-3 times to obtain a solid substance I, and carrying out vacuum drying on the solid substance I at the temperature of 40-55 ℃ for 8-10 hours to obtain the composite antibacterial agent.

Nano tin dioxide, Ti₃C₂T_XIs an inorganic antibacterial agent and is easy to agglomerate when used independently. The nano tin dioxide is uniformly distributed on the Ti by ultrasonic mixing₃C₂T_XThe interlayer of the nano particles solves the problem that the nano particles are difficult to disperse uniformly, and is helpful to prevent the self-agglomeration of the nano particles. Ti₃C₂T_XThe excellent conductivity is beneficial to the formation of more stable photo-generated electron-hole pairs by the nano tin dioxide, so that the catalytic antibacterial effect is synergistically improved. Ti₃C₂T_XHas antioxidant function, so that no additional antioxidant is required to be added into the polyether polyol composition, and Ti₃C₂T_XAfter being oxidized, can also generate inorganic antibacterial agent TiO₂And the antibacterial effect is continuously exerted. The chitosan is a natural polymer bacteriostatic agent, has higher cationic charge density, is tightly combined with the effective components of the inorganic composite antibacterial liquid through electrostatic action, and the natural polymer antibacterial agent and the inorganic antibacterial agent act together, so that the prepared foam plastic with the antibacterial and mildewproof functions has strong antibacterial and mildewproof performance, good durability, good biocompatibility, low toxicity and more environmental protection.

The composite antibacterial agent also plays a role of a nucleating agent in the preparation of the foam plastic, the nucleating agent particles distributed uniformly are beneficial to preparing high-quality foam with finer and more uniform foam cells, the composite antibacterial agent can play a role in enhancing the foam plastic, and the performance of the foam plastic is improved.

The composite antibacterial agent is easy to cause the rapid increase of the system viscosity, and meanwhile, hydroxyl in the structure and polyisocyanate undergo-NCO/-OH reaction under the action of an organotin catalyst to participate in the foaming reaction to promote the foaming reaction, and the composite antibacterial agent is uniformly and stably existed in the generated foam plastic as an important component of the matrix structure of the foam plastic, so that the composite antibacterial agent is not easy to separate out and has durable and stable antibacterial and mildew-proof properties.

Preferably, the preparation method of the composite antibacterial agent comprises the following steps:

s1, adding 2-4 parts of nano tin dioxide into 76-88 parts of thin Ti layer with the concentration of 1-8mg/mL according to parts by weight₃C₂T_XIn the water dispersion, ultrasonic dispersion treatment is carried out for 0.5-2h under the conditions of room temperature, 200-400W and 30-40kHz to obtain inorganic composite antibacterial liquid;

s2, dropwise adding ammonia water into the inorganic composite antibacterial liquid to adjust the pH value to 8, then adding 0.5-1 part of dopamine, stirring at the rotation speed of 150-350rpm for 8-16min, and standing at room temperature for reaction for 24-36h to obtain dopamine co-modified inorganic composite antibacterial liquid;

s3, adding 1-5 parts of chitosan into the dopamine co-modified inorganic composite antibacterial liquid, and stirring and reacting at the rotating speed of 100-300rpm for 10-15 hours at room temperature to obtain an organic-inorganic composite antibacterial liquid;

s4, carrying out vacuum filtration on the organic-inorganic composite antibacterial liquid to obtain a filter cake a, then adding water until the filter cake a is immersed, washing, carrying out suction filtration, washing for 1-3 times to obtain a filter cake b, then adding absolute ethyl alcohol until the filter cake b is immersed, carrying out alcohol washing, carrying out suction filtration, and washing for 1-3 times to obtain a solid substance I, and carrying out vacuum drying on the solid substance I at the temperature of 40-55 ℃ for 8-10 hours to obtain the composite antibacterial agent.

Co-modification of thin Ti layer by dopamine₃C₂T_XAnd nano tin dioxide, so that the nano tin dioxide can be in a thin layer of Ti₃C₂T_XThe nano-sheets are firmly combined and are not easy to migrate, the self-polymerization of dispersed particles is effectively inhibited, and the stability of a dispersion system is ensured. Furthermore, a thin layer of Ti₃C₂T_XThe specific surface area of the inorganic catalyst is improved by compounding with nano tin dioxide, and dopamine is in a thin layer Ti₃C₂T_XThe surface of the nano tin dioxide is connected with more functional groups with stronger activity, such as hydroxyl, amino, carboxyl and the like, so that the thin Ti layer can be enhanced₃C₂T_XAnd the compatibility and the electrostatic action of the nano tin dioxide compound and the natural organic polymer antibacterial agent chitosan, so that the nano tin dioxide compound and the natural organic polymer antibacterial agent chitosan are combined more closely.

After the dopamine modification, the composite antibacterial agent is more uniformly and stably distributed in a reaction system for generating the foam plastic by a one-step method, and the composite antibacterial agent is used as a nucleating agent to promote the prepared foam to be finer and more uniform, so that the performance of the foam plastic is further improved. And because the hydroxyl in the structure is richer, more hydroxyl participates in the foaming reaction, the foaming reaction is promoted to be carried out, and the hydroxyl stably and uniformly exists in the foam plastic structure, so that the antibacterial and mildew-proof properties are more durable and stable.

Has the advantages that: the invention adopts a one-step method to prepare the foamed plastic, has simple process and low energy consumption and has few steps; the obtained foam plastic with the antibacterial and mildewproof functions has fine, dense, uniform and high-quality cells, good mechanical properties and excellent, lasting and stable antibacterial and mildewproof effects.

Detailed Description

The raw materials used in the examples were as follows:

polyether polyol 303 (glycerol polyoxypropylene ether), hydroxyl value: 550mgKOH/g, southwest City modest and chemical Co.

Polyether polyol 204 (propylene glycol and propylene oxide adduct), hydroxyl value: 280mgKOH/g, southeast City modest and chemical Co.

Toluene diisocyanate, CAS No.: 584-84-9, Shandong Leong New Material science and technology, Inc.

Dibutyl phthalate, CAS No.: 84-74-2, Dode chemical, Inc., Guangzhou.

Triethanolamine, CAS No.: 102-71-6, Shandong province chemical Co., Ltd.

Cyclopentane, CAS number: 287-92-3, Shandong Xu Chen chemical science and technology Co.

Silicone oil AK8805, viscosity (25 ℃): 1200mpa.s, mesde chemist gmbh, Jiangsu.

Nano tin dioxide, CAS number: 18282-10-5, type: YC-Sn20, purity: 99.9%, particle size: 20-30nm, Shanghai Yingyun New Material Co.

Thin layer of Ti₃C₂T_XAqueous dispersion, CAS No.: 12363-89-2, concentration: 5mg/mL, plate diameter: 2-5 μm, thickness: 3-5nm, Xian Qiyue Biotech Co., Ltd.

Chitosan, CAS No.: 9012-76-4, viscosity: 200mpa.s, deacetylation degree not less than 90%, Qingdao cloud biotechnology limited.

Dopamine, CAS number: 51-61-6, cat #: ZL-01310021, West Aze Biotech, Inc.

Ammonia water, concentration: 25%, CAS number: 1336-21-6, Jinan Chuang chemical Co.

Example 1

The preparation method of the foam plastic with the antibacterial and mildewproof functions comprises the following steps:

(1) according to the weight portion, 60 portions of polyol composition and 1 portion of composite antibacterial agent are evenly mixed under the condition of 25 ℃ and 50% of relative humidity; adding 60 parts of polyisocyanate, stirring at the rotating speed of 600rpm for 25s, injecting into a mold preheated to 80 ℃, and carrying out foaming molding at 80 ℃ for 5min to obtain molded foam plastic;

(2) and putting the formed foam plastic and the mold into a 90 ℃ oven to be dried for 3h, naturally cooling to room temperature, and stripping and taking out the foam plastic from the mold to obtain the foam plastic.

The polyisocyanate is Toluene Diisocyanate (TDI).

The polyol composition comprises the following components in parts by weight: 100 parts of polyol, 4 parts of plasticizer, 5 parts of catalyst, 8 parts of foaming agent and 4 parts of foam stabilizer.

The polyol is a mixture of 64 parts by weight of polyether polyol 303 and 36 parts by weight of polyether polyol 204.

The plasticizer is dibutyl phthalate.

The catalyst is triethanolamine.

The foaming agent is prepared from cyclopentane and water in a mass ratio of 1: 3.4.

The foam stabilizer is silicone oil AK 8805.

The preparation method of the composite antibacterial agent comprises the following steps:

s1, adding 3 parts of nano tin dioxide into 80 parts of thin Ti layer with the concentration of 3mg/mL in parts by weight₃C₂T_XPerforming ultrasonic dispersion treatment on the aqueous dispersion for 1h at room temperature and 300W and 30kHz to obtain an inorganic composite antibacterial liquid;

s2, adding 3 parts of chitosan into the inorganic composite antibacterial liquid, and stirring and reacting at the room temperature at the rotating speed of 200rpm for 12 hours to obtain an organic-inorganic composite antibacterial liquid;

s3, carrying out vacuum filtration on the organic-inorganic composite antibacterial liquid to obtain a filter cake a, then adding water until the filter cake a is immersed, washing, carrying out suction filtration, washing with water for 3 times to obtain a filter cake b, then adding absolute ethyl alcohol until the filter cake b is immersed, carrying out alcohol washing, carrying out suction filtration, and washing with alcohol for 3 times to obtain a solid substance I, and carrying out vacuum drying on the solid substance I at 45 ℃ for 10 hours to obtain the composite antibacterial agent.

Example 2

The preparation method of the foam plastic with the antibacterial and mildewproof functions comprises the following steps:

(1) according to the weight portion, 60 portions of polyol composition and 1 portion of composite antibacterial agent are evenly mixed under the condition of 25 ℃ and 50% of relative humidity; adding 60 parts of polyisocyanate, stirring at the rotating speed of 600rpm for 25s, injecting into a mold preheated to 80 ℃, and carrying out foaming molding at 80 ℃ for 5min to obtain molded foam plastic;

(2) and putting the formed foam plastic and the mold into a 90 ℃ oven to be dried for 3h, naturally cooling to room temperature, and stripping and taking out the foam plastic from the mold to obtain the foam plastic.

The polyisocyanate is Toluene Diisocyanate (TDI).

The polyol composition comprises the following components in parts by weight: 100 parts of polyol, 4 parts of plasticizer, 5 parts of catalyst, 8 parts of foaming agent and 4 parts of foam stabilizer.

The polyol is a mixture of 64 parts by weight of polyether polyol 303 and 36 parts by weight of polyether polyol 204.

The plasticizer is dibutyl phthalate.

The catalyst is dibutyltin dilaurate.

The foaming agent is prepared from cyclopentane and water in a mass ratio of 1: 3.4.

The foam stabilizer is silicone oil AK 8805.

The preparation method of the composite antibacterial agent comprises the following steps:

s1, adding 3 parts of nano tin dioxide into 80 parts of thin Ti layer with the concentration of 3mg/mL in parts by weight₃C₂T_XPerforming ultrasonic dispersion treatment on the aqueous dispersion for 1h at room temperature and 300W and 30kHz to obtain an inorganic composite antibacterial liquid;

s2, adding 3 parts of chitosan into the inorganic composite antibacterial liquid, and stirring and reacting at the room temperature at the rotating speed of 200rpm for 12 hours to obtain an organic-inorganic composite antibacterial liquid;

s3, carrying out vacuum filtration on the organic-inorganic composite antibacterial liquid to obtain a filter cake a, then adding water until the filter cake a is immersed, washing, carrying out suction filtration, washing with water for 3 times to obtain a filter cake b, then adding absolute ethyl alcohol until the filter cake b is immersed, carrying out alcohol washing, carrying out suction filtration, and washing with alcohol for 3 times to obtain a solid substance I, and carrying out vacuum drying on the solid substance I at 45 ℃ for 10 hours to obtain the composite antibacterial agent.

Example 3

The preparation method of the foam plastic with the antibacterial and mildewproof functions comprises the following steps:

(1) according to the weight portion, 60 portions of polyol composition and 1 portion of composite antibacterial agent are evenly mixed under the condition of 25 ℃ and 50% of relative humidity; adding 60 parts of polyisocyanate, stirring at the rotating speed of 600rpm for 25s, injecting into a mold preheated to 80 ℃, and carrying out foaming molding at 80 ℃ for 5min to obtain molded foam plastic;

(2) and putting the formed foam plastic and the mold into a 90 ℃ oven to be dried for 3h, naturally cooling to room temperature, and stripping and taking out the foam plastic from the mold to obtain the foam plastic.

The polyisocyanate is Toluene Diisocyanate (TDI).

The polyol composition comprises the following components in parts by weight: 100 parts of polyol, 4 parts of plasticizer, 5 parts of catalyst, 8 parts of foaming agent and 4 parts of foam stabilizer.

The polyol is a mixture of 64 parts by weight of polyether polyol 303 and 36 parts by weight of polyether polyol 204.

The plasticizer is dibutyl phthalate.

The catalyst is prepared from dibutyltin dilaurate and triethanolamine in a mass ratio of 1.8: 1.

The foaming agent is prepared from cyclopentane and water in a mass ratio of 1: 3.4.

The foam stabilizer is silicone oil AK 8805.

The preparation method of the composite antibacterial agent comprises the following steps:

s1, adding 3 parts of nano tin dioxide into 80 parts of thin Ti layer with the concentration of 3mg/mL in parts by weight₃C₂T_XPerforming ultrasonic dispersion treatment on the aqueous dispersion for 1h at room temperature and 300W and 30kHz to obtain an inorganic composite antibacterial liquid;

s2, adding 3 parts of chitosan into the inorganic composite antibacterial liquid, and stirring and reacting at the room temperature at the rotating speed of 200rpm for 12 hours to obtain an organic-inorganic composite antibacterial liquid;

s3, carrying out vacuum filtration on the organic-inorganic composite antibacterial liquid to obtain a filter cake a, then adding water until the filter cake a is immersed, washing, carrying out suction filtration, washing with water for 3 times to obtain a filter cake b, then adding absolute ethyl alcohol until the filter cake b is immersed, carrying out alcohol washing, carrying out suction filtration, and washing with alcohol for 3 times to obtain a solid substance I, and carrying out vacuum drying on the solid substance I at 45 ℃ for 10 hours to obtain the composite antibacterial agent.

Example 4

The preparation method of the foam plastic with the antibacterial and mildewproof functions comprises the following steps:

(1) according to the weight portion, 60 portions of polyol composition and 1 portion of composite antibacterial agent are evenly mixed under the condition of 25 ℃ and 50% of relative humidity; adding 60 parts of polyisocyanate, stirring at the rotating speed of 600rpm for 25s, injecting into a mold preheated to 80 ℃, and carrying out foaming molding at 80 ℃ for 5min to obtain molded foam plastic;

(2) and putting the formed foam plastic and the mold into a 90 ℃ oven to be dried for 3h, naturally cooling to room temperature, and stripping and taking out the foam plastic from the mold to obtain the foam plastic.

The polyisocyanate is Toluene Diisocyanate (TDI).

The polyol composition comprises the following components in parts by weight: 100 parts of polyol, 4 parts of plasticizer, 5 parts of catalyst, 8 parts of foaming agent and 4 parts of foam stabilizer.

The polyol is a mixture of 64 parts by weight of polyether polyol 303 and 36 parts by weight of polyether polyol 204.

The plasticizer is dibutyl phthalate.

The catalyst is prepared from dibutyltin dilaurate and triethanolamine in a mass ratio of 1.8: 1.

The foaming agent is prepared from cyclopentane and water in a mass ratio of 1: 3.4.

The foam stabilizer is silicone oil AK 8805.

The preparation method of the composite antibacterial agent comprises the following steps:

s1, adding 3 parts of nano tin dioxide into 80 parts of thin Ti layer with the concentration of 3mg/mL in parts by weight₃C₂T_XPerforming ultrasonic dispersion treatment on the aqueous dispersion for 1h at room temperature and 300W and 30kHz to obtain an inorganic composite antibacterial liquid;

s2, dropwise adding ammonia water into the inorganic composite antibacterial liquid to adjust the pH value to 8, then adding 0.8 part of dopamine, stirring at the rotating speed of 200rpm for 12min, and standing at room temperature for reaction for 28h to obtain dopamine co-modified inorganic composite antibacterial liquid;

s3, adding 3 parts of chitosan into the dopamine co-modified inorganic composite antibacterial liquid, and stirring and reacting at the room temperature at the rotating speed of 200rpm for 12 hours to obtain an organic-inorganic composite antibacterial liquid;

s4, carrying out vacuum filtration on the organic-inorganic composite antibacterial liquid to obtain a filter cake a, then adding water until the filter cake a is immersed, washing, carrying out suction filtration, washing with water for 3 times to obtain a filter cake b, then adding absolute ethyl alcohol until the filter cake b is immersed, carrying out alcohol washing, carrying out suction filtration, and washing with alcohol for 3 times to obtain a solid substance I, and carrying out vacuum drying on the solid substance I at 45 ℃ for 10 hours to obtain the composite antibacterial agent.

Comparative example 1

The preparation method of the foam plastic with the antibacterial and mildewproof functions comprises the following steps:

(1) according to the parts by weight, 60 parts of polyol composition and 1 part of composite antibacterial agent are uniformly mixed at 25 ℃, then 60 parts of polyisocyanate are added, the mixture is stirred at the rotating speed of 600rpm for 25s, then the mixture is injected into a mold preheated to 50 ℃, and the mixture is foamed and molded at 50 ℃ for 5min to obtain molded foam plastic;

(2) and putting the formed foam plastic and the mold into a 90 ℃ oven to be dried for 3h, naturally cooling to room temperature, and stripping and taking out the foam plastic from the mold to obtain the foam plastic.

The polyisocyanate is Toluene Diisocyanate (TDI).

The polyol composition comprises the following components in parts by weight: 100 parts of polyol, 4 parts of plasticizer, 5 parts of catalyst, 8 parts of foaming agent and 4 parts of foam stabilizer.

The polyol is a mixture of 64 parts by weight of polyether polyol 303 and 36 parts by weight of polyether polyol 204.

The plasticizer is dibutyl phthalate.

The catalyst is triethanolamine.

The foaming agent is prepared from cyclopentane and water in a mass ratio of 1: 3.4.

The foam stabilizer is silicone oil AK 8805.

The preparation method of the composite antibacterial agent comprises the following steps:

s1, adding 3 parts of nano tin dioxide into 80 parts of water by weight, and performing ultrasonic dispersion treatment for 1 hour at room temperature under the conditions of 300W and 30kHz to obtain inorganic antibacterial liquid;

s2, adding 3 parts of chitosan into the inorganic antibacterial liquid, and stirring and reacting at the room temperature at the rotating speed of 200rpm for 12 hours to obtain an organic-inorganic composite antibacterial liquid;

s3, carrying out vacuum filtration on the organic-inorganic composite antibacterial liquid to obtain a filter cake a, then adding water until the filter cake a is immersed, washing, carrying out suction filtration, washing with water for 3 times to obtain a filter cake b, then adding absolute ethyl alcohol until the filter cake b is immersed, carrying out alcohol washing, carrying out suction filtration, and washing with alcohol for 3 times to obtain a solid substance I, and carrying out vacuum drying on the solid substance I at 45 ℃ for 10 hours to obtain the composite antibacterial agent.

Comparative example 2

The preparation method of the foam plastic with the antibacterial and mildewproof functions comprises the following steps:

(1) according to the parts by weight, 60 parts of polyol composition and 1 part of composite antibacterial agent are uniformly mixed at 25 ℃, then 60 parts of polyisocyanate are added, the mixture is stirred at the rotating speed of 600rpm for 25s, then the mixture is injected into a mold preheated to 50 ℃, and the mixture is foamed and molded at 50 ℃ for 5min to obtain molded foam plastic;

(2) and putting the formed foam plastic and the mold into a 90 ℃ oven to be dried for 3h, naturally cooling to room temperature, and stripping and taking out the foam plastic from the mold to obtain the foam plastic.

The polyisocyanate is Toluene Diisocyanate (TDI).

The polyol composition comprises the following components in parts by weight: 100 parts of polyol, 4 parts of plasticizer, 5 parts of catalyst, 8 parts of foaming agent and 4 parts of foam stabilizer.

The polyol is a mixture of 64 parts by weight of polyether polyol 303 and 36 parts by weight of polyether polyol 204.

The plasticizer is dibutyl phthalate.

The catalyst is triethanolamine.

The foaming agent is prepared from cyclopentane and water in a mass ratio of 1: 3.4.

The foam stabilizer is silicone oil AK 8805.

The preparation method of the composite antibacterial agent comprises the following steps:

s1, according to parts by weight, 83 parts of thin-layer Ti with the concentration of 3mg/mL₃C₂T_XIn an aqueous dispersion at room temperature of 30 deg.CCarrying out ultrasonic dispersion treatment for 1h under the conditions of 0W and 30kHz to obtain inorganic antibacterial liquid;

s2, adding 3 parts of chitosan into the inorganic antibacterial liquid, and stirring and reacting at the room temperature at the rotating speed of 200rpm for 12 hours to obtain an organic-inorganic composite antibacterial liquid;

s3, carrying out vacuum filtration on the organic-inorganic composite antibacterial liquid to obtain a filter cake a, then adding water until the filter cake a is immersed, washing, carrying out suction filtration, washing with water for 3 times to obtain a filter cake b, then adding absolute ethyl alcohol until the filter cake b is immersed, carrying out alcohol washing, carrying out suction filtration, and washing with alcohol for 3 times to obtain a solid substance I, and carrying out vacuum drying on the solid substance I at 45 ℃ for 10 hours to obtain the composite antibacterial agent.

Test example 1

The foam plastics with antibacterial and mildewproof functions prepared in each example are subjected to basic performance tests, and the detection results are shown in table 1.

(1) And (3) testing the opening rate: test method referring to GB/T10799-.

(2) Size change rate test: the test method refers to GB/T8811-: the test was carried out at a relative humidity of 50% and a temperature of 23 ℃ for a total time of 48 hours, and the arithmetic mean of the dimensional change rates of the length, width and thickness was taken as the sample dimensional change rate, and 3 groups of the test samples were averaged for each test, and the conditions were adjusted at a relative humidity of 50% and a temperature of 23 ℃.

Table 1: basic performance test of foam plastic with antibacterial and mildewproof functions

	Volume open area ratio/%)	Rate of change in dimension/%)
			Example 1	92	0.36
Example 2	28	0.41
			Example 3	58	0.30
Example 4	65	0.22
			Comparative example 1	90	0.52
Comparative example 2	88	0.54

Test example 2

The foam plastics with antibacterial and mildewproof functions prepared in each example are subjected to mechanical property tests, and the detection results are shown in table 2.

(1) And (3) testing the compression performance: the test method refers to GB/T8813-: 400mm 50mm, the conditions of 50% relative humidity, 23 ℃ conditions for conditioning and testing, using method A, test speed of 5mm/min, test compression strength, each test 5 groups of the average.

(2) And (3) testing tensile property: the test method refers to GB/T9641-1988 rigid foam plastic tensile property test method, and the sample size is as follows: the maximum tensile strength was measured by conditioning and testing at a relative humidity of 50% and a temperature of 23 ℃ at 400 mm. times.400 mm. times.50 mm, and 5 groups for each test were averaged.

(3) And (3) testing the bending property: the test method refers to GB/T8812.2-2007 Standard for determination of bending property of rigid foam, part 2, determination of bending strength and apparent bending elastic modulus, the state adjustment and test are carried out under the conditions of 50% of relative humidity and 23 ℃, and the size of a sample is as follows: 350mm × 100mm × 25mm, the test speed is 20mm/min, the bending strength is tested, and 5 groups of tests in each case are averaged.

Table 2: foam plastic mechanical property test with antibacterial and mildew-proof functions

Test example 3

(1) And (3) detecting antibacterial performance: the test method refers to the standard of GB/T31402-2015 test method for surface antibacterial property of plastic plastics, and the test: the nutrient agar method comprises testing plastic size of 50mm × 50mm and thickness of 4mm, testing strains of Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 6538, and selecting strain with concentration of 5.0 × 10⁵The cfu/mL diluted solution was used as the experimental bacterial solution, and the results are shown in Table 2.

(2) And (3) detecting the anti-mildew performance: the test method refers to the standard GB/T24128-: the nutrient agar method comprises testing plastic with size of 40mm × 40mm and thickness of 4mm, and the main strains are Aspergillus niger ATCC 6275 and AsterisCBS 628.66, Penicillium funiculosum ATCC 9644, Trichoderma longibrachiatum ATCC 13631 and Mucor globosum ATCC 6205, cultured with the above strains and made to a concentration of 6.0X 10⁶And (3) mixing the five mould spore suspensions into a mixed bacterial liquid before use.

Table 3: test result of antibacterial and mildewproof performance of foam plastic with antibacterial and mildewproof functions

Example 1 the tertiary amine catalyst used alone has a faster foaming speed and a slower gelling speed than example 2 which uses the organotin catalyst alone, but the foam obtained has a high open cell content, but too fast foaming tends to result in non-uniform cell size and non-uniform distribution, resulting in a large dimensional change rate and having an influence on mechanical properties. Example 2 gel fast, foaming slow, the foamed plastic obtained is low in open cell rate, high in closed cell rate, easy to cause the foamed plastic to expand and deform by heating, and large in size change rate. Example 3 when the tertiary amine catalyst and the organotin catalyst were used in combination, the rate of formation of the foaming gas and the rate of formation of the polymer were easily adjusted and could be coordinated, resulting in more uniform foaming, production of ideal foams, and better dimensional stability and mechanical properties.

In comparison with the comparative examples, the examples use a thin Ti layer₃C₂T_XAnd nano tin dioxide as inorganic antiseptic, and the nano tin dioxide is distributed homogeneously in Ti₃C₂T_XThe interlayer of the nano particles solves the problem that the nano particles are difficult to disperse uniformly, and is helpful to prevent the self-agglomeration of the nano particles. Then the composite antibacterial agent is compounded with organic antibacterial agent chitosan to obtain the composite antibacterial agent which can jointly play the antibacterial and mildewproof role. The prepared foam plastic with the antibacterial and mildewproof functions has strong antibacterial and mildewproof performance, good biocompatibility and more environmental protection.

The composite antibacterial agent particles also play a role of nucleating agent in the preparation of the foam plastic, so that the nucleating agent particles distributed uniformly are beneficial to preparing high-quality foam with finer and more uniform foam cells, can play a role in enhancing the foam plastic and improve the performance of the foam plastic. And the viscosity of the system is easily and rapidly increased due to the composite antibacterial agent, and meanwhile, the structure contains hydroxyl, so that the composite antibacterial agent can participate in the foaming reaction under the action of an organic tin catalyst to promote the foaming reaction, and the composite antibacterial agent stably and uniformly exists in a foam plastic matrix structure, so that the antibacterial and mildew-proof performance is stronger, and the composite antibacterial agent is more durable and stable.

Example 4 Co-modification of thin Ti by dopamine₃C₂T_XAnd the nano tin dioxide further ensures the stability of a dispersion system, and more active functional groups are connected to the surface of the inorganic antibacterial agent, so that the interaction between the organic antibacterial agent and the inorganic antibacterial agent is enhanced, the closer combination is realized, and the performances of the foam plastic are further improved.