A two-component high-efficiency antibacterial water-based acrylic adhesive and a preparation method thereof

Abstract

The application provides a two-component high-efficiency antibacterial water-based acrylic adhesive and a preparation method thereof. The two-component water-based acrylic adhesive comprises component A and component B, wherein the component A is a water-based acrylic emulsion, and the component B is an aqueous solution of guanidine salt polymer and polyethylene glycol block copolymer, which is a flocculant and also an antibacterial agent. In use, the component A and the component B are respectively sprayed from a two-component spray gun, mixed in the air, and the component B causes the component A to break emulsion to form a film to generate initial adhesion, realize wet bonding, and also has antibacterial performance to provide excellent antibacterial performance for the adhesive layer. The two-component antibacterial water-based acrylic adhesive uses water as a solvent, is halogen-free, green and environmentally friendly, has good initial adhesion, high bonding strength, good heat resistance, good adhesion to various substrates, and excellent antibacterial performance.

Description

Technical Field

[0001] This invention belongs to the field of functional polymer materials, specifically relating to a two-component, high-efficiency antibacterial waterborne acrylic spray adhesive and its preparation method. Background Technology

[0002] Currently, chemical products containing volatile organic compounds (VOCs) are subject to strict restrictions, and the adhesive industry is gradually shifting from oil-based to water-based adhesives. Water-based adhesives, such as water-based chloroprene, water-based acrylic, and water-based polyurethane, use water as a solvent, are low in VOCs, and are environmentally friendly. They quickly establish initial adhesion through demulsification and film formation, providing immediate adhesion without penetration, making them convenient and efficient. They are widely used for bonding porous materials such as sofa sponges, foams, fabrics, leather, paper, and wood. However, these substrates are highly hygroscopic, and water-based adhesives contain a large number of hydrophilic groups, making the adhesive layer prone to bacterial growth in humid environments, which can endanger human health. Patent CN111662653A introduces sodium benzoate and chitosan into water-based chloroprene adhesive formulations to improve the antibacterial properties of the adhesive layer. However, the antibacterial properties of chitosan and sodium benzoate are limited, with an antibacterial rate of only about 90% against Escherichia coli and Staphylococcus aureus.

[0003] Therefore, there is an urgent need in this field for a spray adhesive with superior overall antibacterial properties that can maintain its bactericidal effect efficiently and for a long time. Summary of the Invention

[0004] The purpose of this invention is to provide a two-component antibacterial water-based acrylic spray adhesive to solve the above-mentioned problems. The antibacterial spray adhesive can maintain the bactericidal effect efficiently and for a long time.

[0005] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0006] A two-component antibacterial water-based acrylic spray adhesive, the spray adhesive comprising:

[0007] Component A: Aqueous acrylic emulsion;

[0008] Component B is an aqueous solution of guanidine salt polymer and polyethylene glycol block copolymer;

[0009] The mass ratio of component A to component B is 5:1 to 20:1.

[0010] This invention uses guanidine salt polymer and polyethylene glycol block copolymer as a flocculant in a two-component spray adhesive. After block copolymerization between polyethylene glycol and guanidine salt polymer, not only is the overall ionic strength of guanidine salt polymer dispersed, improving the initial tack and open time of the two-component spray adhesive, but there is also a synergistic antibacterial effect between polyethylene glycol and guanidine salt polymer. The guanidine salt polymer is responsible for killing bacteria, while the polyethylene glycol segments are responsible for resisting bacterial adhesion, preventing the formation of bacterial biofilms, and reducing bacterial resistance. The synergistic effect of the two provides excellent antibacterial properties for the final adhesive layer.

[0011] In this invention, the glass transition temperature of the aqueous acrylic emulsion is -40 to 0°C, preferably -30 to 5°C.

[0012] In this invention, the preparation method of the aqueous acrylic emulsion includes the following steps:

[0013] S1: Add water and emulsifier to the emulsification tank and stir. Continue to add the mixture of polymer monomers, functional monomers and crosslinking monomers and stir to obtain a pre-emulsion.

[0014] S2: Add water and part of the pre-emulsion to the reactor, stir and heat, add initiator solution, heat and keep warm to obtain seed emulsion; add the remaining pre-emulsion monomer and keep warm, add initiator solution, heat and keep warm after addition, and after the reaction is completed, add post-treatment agent to eliminate unreacted monomers.

[0015] S3: Cool down, add pH adjuster, add adipic acid dihydrazide, stir and filter out the material.

[0016] In this invention, the emulsifier in S1 is selected from one or more of sodium dodecyl sulfate (SDS), sodium tridecyl alcohol polyoxyethylene ether sulfate (CM-30), and sodium alkyl polyethylene glycol ether sulfate (EPA-073), preferably SDS; preferably, the amount of the emulsifier accounts for 0.6-1.5% of the total mass of the total monomer mixture.

[0017] In this invention, the polymer monomer in S1 is selected from (meth)acrylate monomers or a mixture of (meth)acrylate monomers and vinyl monomers; wherein, the (meth)acrylate monomer is selected from one or more of alkyl (meth)acrylates with alkyl chains containing 1-20 carbon atoms, preferably one or more of methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, cyclohexyl (meth)acrylate, isooctyl (meth)acrylate, dodecyl (meth)acrylate, and octadecyl (meth)acrylate, more preferably methyl methacrylate, methyl acrylate, and propylene. The polymer monomer is selected from one or more of n-butyl acrylate, n-butyl methacrylate, and isooctyl acrylate; the vinyl monomer is selected from one or more of vinyl esters of carboxylic acids containing ≤20 carbon atoms and vinyl aromatic compounds containing ≤20 carbon atoms; the vinyl ester of carboxylic acids containing ≤20 carbon atoms is one or more of vinyl acetate, vinyl propionate, vinyl laurate, or vinyl stearate; the vinyl aromatic compound containing ≤20 carbon atoms is selected from one or more of styrene, α-methylstyrene, p-methylstyrene, and vinyltoluene; preferably, the amount of the polymer monomer accounts for 90%-99.8% of the total mass of the total monomer mixture.

[0018] In this invention, the functional monomer in S1 is selected from one or more olefinic unsaturated monomers containing carboxyl, sulfonic acid, hydroxyl, or amide functional groups; wherein, the carboxyl-containing olefinic unsaturated monomer is preferably one or more of acrylic acid, methacrylic acid, maleic acid, and itaconic acid; the sulfonic acid-containing olefinic unsaturated monomer is preferably one or more of sodium p-styrene sulfonate, sodium vinyl sulfonate, and sodium allyl ether hydroxypropyl sulfonate; the hydroxyl-containing olefinic unsaturated monomer is preferably one or more of hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxyethyl acrylate, and hydroxypropyl acrylate; the amide-containing olefinic unsaturated monomer is acrylamide; preferably, the amount of the functional monomer is 0.1%-5% of the total mass of the total monomer mixture.

[0019] In this invention, the crosslinking monomer in S1 is diacetone acrylamide; preferably, the amount of the crosslinking monomer accounts for 0.1%-5% of the total mass of the total monomer mixture.

[0020] In this invention, the first stirring time in S1 is 20-60 min, and the second stirring time is 50-120 min.

[0021] In this invention, the initiator in S2 is a thermal initiator and / or a redox initiator; wherein, the thermal initiator is preferably one or more of ammonium persulfate, potassium persulfate, sodium persulfate, tert-butyl hydroperoxide, hydrogen peroxide, benzoyl peroxide (BPO), and azobisisobutyronitrile (AIBN); the redox initiator is composed of an oxidant and a reducing agent, wherein the oxidant is preferably one or more of ammonium persulfate, potassium persulfate, sodium persulfate, tert-butyl hydroperoxide, hydrogen peroxide, BPO, and AIBN, and the reducing agent is preferably one or more of sodium sulfite, sodium bisulfite, sodium formaldehyde sulfoxylate, and ascorbic acid; preferably, the amount of the initiator accounts for 0.2-0.5% of the total mass of the monomer mixture, more preferably 0.3-0.4%.

[0022] In this invention, the portion of pre-emulsion added in S2 accounts for 5%-15% of the total mass of the emulsion, preferably 6-10%.

[0023] In this invention, after S2 is added to the initiator solution, the temperature is raised to 83-85°C. After the pre-emulsified monomer is added, the temperature is raised to 85-88°C and held for 20-40 minutes.

[0024] In this invention, the post-treatment agent in S2 is an oxidant and a reducing agent; preferably, the oxidant is one or more of hydrogen peroxide, tert-butyl hydrogen peroxide, sodium persulfate, potassium persulfate, and ammonium persulfate; the reducing agent is one or more of sodium sulfite, sodium bisulfite, sodium formaldehyde sulfoxylate, and ascorbic acid; preferably, the mass ratio of the oxidant to the reducing agent is 1:1 to 3:1; preferably, the amount of the post-treatment agent is 0.1-0.5% of the total mass of the monomer mixture.

[0025] In this invention, the pH adjuster mentioned in S3 is one or more of sodium hydroxide, potassium hydroxide, ammonia, ethanolamine, and triethylamine.

[0026] In this invention, S3 is added to adipic acid dihydrazide and stirred for 20-40 minutes.

[0027] In this invention, the method for preparing the aqueous solution of component B guanidine salt polymer and polyethylene glycol block copolymer includes the following steps:

[0028] SS1: Add guanidine salt and polyamine compound to the reactor, heat to prepolymerize, continue heating to react, cool down and add water to prepare guanidine salt polymer aqueous solution;

[0029] SS2: Add water and epoxy-terminated polyethylene glycol to the reactor, heat and stir until the epoxy-terminated polyethylene glycol dissolves to obtain an aqueous solution of epoxy-terminated polyethylene glycol;

[0030] SS3: Add an aqueous solution of epoxy-terminated polyethylene glycol to an aqueous solution of guanidine salt polymer to carry out the polymerization reaction, and dilute the aqueous solution of the reaction product.

[0031] In this invention, the guanidine salt in SS1 is one or more of guanidine hydrochloride, metformin hydrochloride, guanidine phosphate, metformin phosphate, guanidine sulfate, and metformin sulfate, with guanidine hydrochloride being preferred.

[0032] In this invention, the polyamino compound SS1 contains at least two primary amino groups, preferably one or more of hexamethylenediamine, pentanediamine, butanediamine, isophoronediamine, N-(2-hydroxyethyl)ethylenediamine, 1,4-diaminocyclohexane, and bis(4-aminocyclohexane)methane, and more preferably hexamethylenediamine.

[0033] In this invention, the molar ratio of the guanidine salt to the polyamine compound in SS1 is 1:(1.05-1.3), preferably 1:(1.1-1.2).

[0034] In this invention, the SS1 is first heated to 110-130℃ and reacted for 1-2 hours, and then heated to 140-160℃ and reacted for 3-4 hours.

[0035] In this invention, the concentration of the guanidine salt polymer aqueous solution in SS1 is 20-30 wt%.

[0036] In this invention, the epoxy-terminated polyethylene glycol in SS2 is polyethylene glycol diglycidyl ether and / or polyethylene glycol monoglycidyl ether, with structures of Formula 1 and Formula 2, respectively:

[0037]

[0038]

[0039] Preferably, the epoxy-terminated polyethylene glycol has a molecular weight of 200-6000, more preferably 400-2000.

[0040] In this invention, the SS2 is heated to 50-60°C.

[0041] In this invention, the concentration of the epoxy-terminated polyethylene glycol aqueous solution in SS2 is 20-30 wt%.

[0042] In this invention, the mass ratio of guanidine salt polymer and epoxy-terminated polyethylene glycol in SS3 is 1:(1-6), preferably 1:(2-4).

[0043] In this invention, the concentration of the aqueous solution of the reaction product in SS3 is 1-10%, preferably 2-7%.

[0044] In this invention, the temperature of SS3 is 50-80℃, and the reaction time is 4-6 hours.

[0045] In one embodiment, during use, components A and B are atomized from a two-component spray gun and mixed in the air. Component B causes component A to break down and form a film, generating initial tack and achieving wet bonding. At the same time, component B has antibacterial properties, providing excellent antibacterial properties for the adhesive layer.

[0046] Based on the above technical solution, the positive effects achieved by this invention are as follows:

[0047] (1) It adheres well to various substrates such as wood and metal, has excellent antibacterial properties, and can achieve an antibacterial rate of 99.9% after 2 hours of contact with Escherichia coli (a representative Gram-negative bacterium) and Staphylococcus aureus (a representative Gram-positive bacterium).

[0048] (2) The prepared two-component water-based acrylic spray adhesive uses water as a solvent, is halogen-free, green and environmentally friendly, has good initial adhesion, can be sprayed and bonded immediately, has high bonding strength, can destroy the substrate, has good heat resistance, and does not delaminate after being placed at 80℃ for 3 hours after drying. Attached Figure Description

[0049] Figure 1 Examples, comparative examples, and coating test panels without added antibacterial components are shown, with the "control" group consisting of coating test panels without added antibacterial components, provided by the China Building Materials Academy. Detailed Implementation

[0050] The technical solution of the present invention will be described in further detail below, but the scope of protection of the present invention is not limited to the following description.

[0051] Main raw material sources:

[0052] Methyl methacrylate, 99%, Shandong Weiming Chemical Co., Ltd.

[0053] Styrene, 99%, Henan Tianfu Chemical Co., Ltd.;

[0054] n-Butyl acrylate, 99%, Henan Tianfu Chemical Co., Ltd.;

[0055] Isooctyl acrylate, 99%, Hubei Jusheng Technology Co., Ltd.

[0056] Methacrylic acid, 99%, Henan Tianfu Chemical Co., Ltd.;

[0057] Hydroxyethyl methacrylate, 99%, Henan Tianfu Chemical Co., Ltd.

[0058] Calcium chloride, Tianjin Kemeo Chemical Reagent Co., Ltd.

[0059] SDS, anionic emulsifier, Kao Corporation of Japan;

[0060] Ammonium persulfate, 99%, Tianjin Kemeo Chemical Reagent Co., Ltd.

[0061] tert-butyl hydrogen peroxide, 99% Wuhan Jiakailong Technology Development Co., Ltd.

[0062] Sodium bisulfite, 99%, Henan Tianfu Chemical Co., Ltd.;

[0063] Ammonia solution (concentration 25-28wt), Tianlu Kemio Chemical Reagent Co., Ltd.

[0064] Epoxy-terminated polyethylene glycol, 99% Shanghai Guanyin Biotechnology Co., Ltd.

[0065] Guanidine hydrochloride, 98%, Cangzhou Enke Pharmaceutical Technology Co., Ltd.;

[0066] Hexamethylenediamine, 99%, Henan Tianfu Chemical Co., Ltd.;

[0067] Two-component water-based chloroprene spray adhesive 663, Foshan Oriental Tree New Material Technology Co., Ltd.

[0068] All water mentioned is deionized water; all other raw materials or reagents are purchased from the market unless otherwise specified.

[0069] Performance analysis methods:

[0070] Initial tack test method: The test substrate is a 10*5*3cm sponge with a density of 50D. Use a two-component spray gun to spray the glue onto the sponge surface. Immediately after spraying, fold the sponge in half from the middle and press gently for 5 seconds. Record the distance of the sponge opening within 10 minutes.

[0071] Heat resistance test method: After the adhesive layer of the bonded specimen has dried, place the sponge in an 80℃ oven for 3 hours and record the distance of the sponge delamination;

[0072] Antibacterial test method: The antibacterial properties of the film were determined according to GB / T 21866-2008 standard. The contact time between bacteria and the film was controlled to be 2 hours, and no air bubbles or sterile liquid overflow were required when the film was covered. Test bacteria: Gram-negative bacteria Escherichia coli (E. coli, ATCC25922) and Gram-positive bacteria Staphylococcus aureus (S. aureus, ATCC29213).

[0073] Example 1

[0074] Synthesis of waterborne acrylic resin:

[0075] S1: Preparation of pre-emulsion: Add 300g deionized water and 10g SDS to the emulsification kettle and stir at 400rpm for 20min until the SDS is completely dissolved. Then add 210g styrene monomer, 500g n-butyl acrylate monomer, 250g isooctyl acrylate monomer, 30g methacrylic acid monomer and 10g diacetone acrylamide mixture to the kettle and stir at 500rpm for 50min to obtain a uniform and stable pre-emulsion. The Tg measured by DSC is -18℃. Set aside for later use.

[0076] S2: Emulsion polymerization reaction: 650g of deionized water and 80g of pre-emulsion were added to the reactor, stirred at 300rpm and heated to 80℃. 3.2g of 5.7% ammonium persulfate aqueous solution was added, and then the temperature was raised to 85℃ and kept at that temperature for 1 hour to obtain the seed emulsion. After the temperature was kept at that temperature, the remaining pre-emulsified monomer was slowly added dropwise while the temperature was maintained at 83℃. At the same time, 49.8g of 5.7% ammonium persulfate aqueous solution was added dropwise at a uniform rate for 5 hours. After the pre-emulsified monomer was added, the temperature was raised to 88℃ and kept at that temperature for 30 minutes. 3g of tert-butyl hydroperoxide and 1g of sodium bisulfite were added to eliminate unreacted monomers.

[0077] S3: Cool to 35℃, add ammonia water to adjust the pH of the emulsion to 5, then add 10g of adipic acid dihydrazide, stir for 30 minutes and filter out the material.

[0078] Preparation of flocculants / antibacterial agents:

[0079] SS1: Add 96g guanidine hydrochloride and 127g hexamethylenediamine to the reactor, heat to 120℃ and react for 2h, then heat to 150℃ and react for 4h, cool to 90℃ and add 670g deionized water to obtain a 25wt% guanidine salt polymer aqueous solution.

[0080] SS2: Add 223g of polyethylene glycol diglycidyl ether 2000 and 223g of polyethylene glycol monoglycidyl ether 1000 and 1338g of deionized water to a reaction vessel, heat to 50℃, stir at 300rpm for 30min to obtain a 25wt% epoxy-terminated polyethylene glycol aqueous solution.

[0081] SS3: The epoxy-terminated polyethylene glycol aqueous solution obtained in SS2 was added dropwise to the guanidine salt polymer aqueous solution in SS1 under stirring at 80℃ and 400rpm. After the addition was completed, the reaction continued for 4 hours. After cooling to room temperature, 20kg of deionized water was added to obtain a 3% two-component spray adhesive flocculant / antibacterial agent.

[0082] The antibacterial test results are shown in Table 1, and the corresponding test plates are shown in Table 1. Figure 1 .

[0083] Example 2

[0084] Synthesis of waterborne acrylic resin:

[0085] S1. Preparation of pre-emulsion: Add 300g deionized water and 8g SDS to the emulsification kettle and stir at 400rpm for 60min until the SDS is completely dissolved. Then add 250g styrene monomer, 450g n-butyl acrylate monomer, 250g isooctyl acrylate monomer, 30g methacrylic acid monomer and 20g diacetone acrylamide mixture to the kettle and stir at high speed for 120min to obtain a uniform and stable pre-emulsion. The Tg measured by DSC is -12℃. Set aside for later use.

[0086] S2. Emulsion polymerization reaction: 650g of deionized water and 130g of pre-emulsion were added to the reactor, stirred and heated. When the temperature reached 80℃, 5.4g of 7.4% ammonium persulfate aqueous solution was added. Then the temperature was raised to 85℃ and kept for 1 hour to obtain seed emulsion. After the temperature was kept, the remaining pre-emulsified monomer was slowly added dropwise while the temperature was maintained at 85℃. At the same time, 48.6g of 7.4% ammonium persulfate aqueous solution was added dropwise at a uniform rate for 5 hours. After the pre-emulsified monomer was added, the temperature was raised to 88℃ and kept for 40 minutes. 3g of tert-butyl hydroperoxide and 2g of sodium bisulfite were added to eliminate unreacted monomers.

[0087] S3. Cool down to below 35℃, add ammonia water to adjust the pH of the emulsion to 5, then add 20g of adipic acid dihydrazide, stir for 20 minutes and filter out the material.

[0088] Preparation of flocculants / antibacterial agents:

[0089] SS1: Add 216g guanidine phosphate and 151g hexamethylenediamine to the reactor, heat to 130℃ and react for 1h, then heat to 160℃ and react for 3h, cool to 90℃ and add 856g deionized water to obtain a 30wt% guanidine salt polymer aqueous solution.

[0090] SS2: Add 1468g of polyethylene glycol diglycidyl ether 4000 and 3425g of deionized water to the reactor, heat to 50℃, stir at 300rpm for 30min to obtain a 30wt% epoxy-terminated polyethylene glycol aqueous solution.

[0091] SS3: The epoxy-terminated polyethylene glycol aqueous solution obtained in SS2 was added dropwise to the guanidine salt polymer aqueous solution in SS1 under stirring at 50℃ and 400rpm. After the addition was completed, the reaction continued for 6h. After cooling to room temperature, 24.5kg of deionized water was added to obtain a 6% two-component spray adhesive flocculant / antibacterial agent.

[0092] The antibacterial test results are shown in Table 1, and the corresponding test plates are shown in Table 1. Figure 1 .

[0093] Example 3

[0094] Synthesis of waterborne acrylic resin:

[0095] S1. Preparation of pre-emulsion: Add 300g deionized water and 6g SDS to the emulsification tank and stir at 400rpm for 20min until the SDS is completely dissolved. Then add 105g methyl methacrylate, 630g n-butyl acrylate monomer, 250g isooctyl acrylate monomer, 50g methacrylate monomer, and 5g diacetone acrylamide mixture to the tank and stir at 500rpm for 50min to obtain a uniform and stable pre-emulsion. The Tg measured by DSC is -32℃. Set aside for later use.

[0096] S2. Emulsion polymerization reaction: 650g of deionized water and 200g of pre-emulsion were added to the reactor, stirred and heated. When the temperature reached 80℃, 9g of 9% ammonium persulfate aqueous solution was added. Then the temperature was raised to 85℃ and kept for 1 hour to obtain seed emulsion. After the temperature was kept, the remaining pre-emulsified monomer was slowly added dropwise while the temperature was maintained at 83℃. At the same time, 46g of 9% ammonium persulfate aqueous solution was added dropwise at a uniform rate for 5 hours. After the pre-emulsified monomer was added, the temperature was raised to 88℃ and kept for 20 minutes. 2g of tert-butyl hydroperoxide and 2g of sodium bisulfite were added to eliminate unreacted monomers.

[0097] S3. Cool down to below 35℃, add ammonia water to adjust the pH of the emulsion to 5, then add 5g of adipic acid dihydrazide, stir for 40 minutes and filter out the material.

[0098] Preparation of flocculants / antibacterial agents:

[0099] SS1: Add 96g guanidine hydrochloride and 120g 1,4-diaminocyclohexane to a reaction vessel, heat to 130℃ and react for 2h, then heat to 160℃ and react for 4h, cool to 90℃ and add 864g deionized water to obtain an aqueous solution of guanidine salt polymer.

[0100] SS2: Add 216g of polyethylene glycol diglycidyl ether 2000 and 864g of deionized water to the reactor, heat to 60℃, stir at 300rpm for 30min to obtain a 20wt% epoxy-terminated polyethylene glycol aqueous solution.

[0101] SS3: The epoxy-terminated polyethylene glycol aqueous solution obtained in SS2 was added dropwise to the guanidine salt polymer aqueous solution in SS1 under stirring at 60℃ and 400rpm. After the addition was completed, the reaction continued for 5h. After cooling to room temperature, 19.4kg of deionized water was added to obtain a 2% two-component spray adhesive flocculant / antibacterial agent.

[0102] The antibacterial test results are shown in Table 1, and the corresponding test plates are shown in Table 1. Figure 1 .

[0103] Example 4

[0104] Synthesis of waterborne acrylic resin:

[0105] S1: Preparation of pre-emulsion: Add 300g deionized water and 15g SDS to the emulsification kettle and stir at 400rpm for 20min to ensure complete dissolution of the emulsifier. Then add 220g styrene monomer, 80g methyl methacrylate monomer, 340g n-butyl acrylate monomer, 300g isooctyl acrylate monomer, 10g methacrylate monomer and 50g diacetone acrylamide mixture to the kettle and stir at 500rpm for 50min to obtain a uniform and stable pre-emulsion. The Tg measured by DSC is -7℃. Set aside for later use.

[0106] S2: Emulsion polymerization reaction: 650g of deionized water and 80g of pre-emulsion were added to the reactor, stirred and heated. When the temperature reached 80℃, 3.2g of 3.8% ammonium persulfate aqueous solution was added, and then the temperature was raised to 85℃ and kept for 1 hour to obtain seed emulsion. After the temperature was kept, the remaining pre-emulsified monomer was slowly added dropwise while the temperature was maintained at 83℃. At the same time, 48.8g of 3.8% ammonium persulfate aqueous solution was added dropwise at a uniform rate for 5 hours. After the pre-emulsified monomer was added, the temperature was raised to 88℃ and kept for 30 minutes. 2g of tert-butyl hydroperoxide and 1g of sodium bisulfite were added to eliminate unreacted monomers.

[0107] S3: Cool down to below 35℃, add ammonia water to adjust the pH of the emulsion to 5, then add 50g of adipic acid dihydrazide, stir for 30 minutes and filter out the material.

[0108] Preparation of flocculants / antibacterial agents:

[0109] SS1: Add 165g metformin hydrochloride and 204g isophorone diamine to the reactor, heat to 130℃ and react for 2h, then heat to 160℃ and react for 4h, cool to 90℃ and add 1107g deionized water to obtain a 25wt% guanidine salt polymer aqueous solution.

[0110] SS2: Add 2214g of polyethylene glycol diglycidyl ether 6000 and 6642g of deionized water to the reactor, heat to 60℃, stir at 300rpm for 30min to obtain a 25wt% epoxy-terminated polyethylene glycol aqueous solution.

[0111] SS3: The epoxy-terminated polyethylene glycol aqueous solution obtained in SS2 was added dropwise to the guanidine salt polymer aqueous solution in SS1 under stirring at 60℃ and 400rpm. After the addition was completed, the reaction continued for 5h. After cooling to room temperature, 93kg of deionized water was added to obtain a 10% two-component flocculant / antibacterial agent for spray adhesive.

[0112] The antibacterial test results are shown in Table 1, and the corresponding test plates are shown in Table 1. Figure 1 .

[0113] Example 5

[0114] Synthesis of waterborne acrylic resin:

[0115] S1: Preparation of pre-emulsion: Add 300g deionized water, 7g SDS and 3g EPA-073 to the emulsification tank and stir at 400rpm for 20min to ensure complete dissolution of the emulsifier. Then add 200g methyl methacrylate, 400g n-butyl acrylate monomer, 350g isooctyl acrylate monomer, 20g methacrylate monomer, 20g hydroxyethyl methacrylate and 10g diacetone acrylamide mixture to the tank and stir at high speed for 50min to obtain a uniform and stable pre-emulsion. The Tg measured by DSC is -20℃. Set aside for later use.

[0116] S2: Emulsion polymerization reaction: 650g of deionized water and 8g of pre-emulsion were added to the reactor, stirred and heated. When the temperature reached 80℃, 3.2g of 5.7% ammonium persulfate aqueous solution was added. Then the temperature was raised to 85℃ and kept for 1 hour to obtain seed emulsion. After the temperature was kept, the remaining pre-emulsified monomer was slowly added dropwise while the temperature was maintained at 83℃. At the same time, 49.7g of 5.7% ammonium persulfate aqueous solution was added dropwise at a uniform rate for 5 hours. After the pre-emulsified monomer was added, the temperature was raised to 88℃ and kept for 30 minutes. 2g of hydrogen peroxide and 1g of sodium bisulfite were added to eliminate unreacted monomers.

[0117] S3: Cool down to below 35℃, add ammonia water to adjust the pH of the emulsion to 5, then add 10g of adipic acid dihydrazide, stir for 30 minutes and filter out the material.

[0118] Preparation of flocculants / antibacterial agents:

[0119] SS1: Add 157g guanidine sulfate and 139g hexamethylenediamine to the reactor, heat to 120℃ and react for 2h, then heat to 150℃ and react for 4h, cool to 90℃ and add 888g deionized water to obtain a 25wt% guanidine salt polymer aqueous solution.

[0120] SS2: Add 592g of polyethylene glycol monoglycidyl ether 1000 and 1776g of deionized water to the reactor, heat to 60℃, stir at 300rpm for 30min to obtain a 25wt% epoxy-terminated polyethylene glycol aqueous solution.

[0121] SS3: The epoxy-terminated polyethylene glycol aqueous solution obtained in SS2 was added dropwise to the guanidine salt polymer aqueous solution in SS1 under stirring at 60℃ and 400rpm. After the addition was completed, the reaction continued for 4h. After cooling to room temperature, 26kg of deionized water was added to obtain a 3% two-component spray adhesive flocculant / antibacterial agent.

[0122] The antibacterial test results are shown in Table 1, and the corresponding test plates are shown in Table 1. Figure 1 .

[0123] Example 6

[0124] Synthesis of waterborne acrylic resin:

[0125] S1: Preparation of pre-emulsion: Add 300g deionized water, 6g SDS and 3g CM-30 to the emulsification tank and stir at 400rpm for 20min to ensure complete dissolution of the emulsifier. Then add 280g methyl methacrylate, 500g n-butyl acrylate monomer, 160g isooctyl acrylate monomer, 30g methacrylate monomer, 20g hydroxyethyl acrylate monomer and 10g diacetone acrylamide mixture to the tank and stir at high speed for 50min to obtain a uniform and stable pre-emulsion. The Tg measured by DSC is -3℃. Set aside for later use.

[0126] S2: Emulsion polymerization reaction: 650g of deionized water and 8g of pre-emulsion were added to the reactor, stirred and heated. When the temperature reached 80℃, 3.2g of 5.7% ammonium persulfate aqueous solution was added. Then the temperature was raised to 85℃ and kept for 1 hour to obtain seed emulsion. After the temperature was kept, the remaining pre-emulsified monomer was slowly added dropwise while the temperature was maintained at 83℃. At the same time, 49.7g of 5.7% ammonium persulfate aqueous solution was added dropwise at a uniform rate for 5 hours. After the pre-emulsified monomer was added, the temperature was raised to 88℃ and kept for 30 minutes. 2g of tert-butyl hydroperoxide and 1g of sodium bisulfite were added to eliminate unreacted monomers.

[0127] S3: Cool down to below 35℃, add ammonia water to adjust the pH of the emulsion to 6, then add 10g of adipic acid dihydrazide, stir for 30 minutes and filter out the material.

[0128] Preparation of flocculants / antibacterial agents:

[0129] SS1: Add 96g guanidine hydrochloride and 127g hexamethylenediamine to the reactor, heat to 120℃ and react for 2h, then heat to 150℃ and react for 4h, cool to 90℃ and add 670g deionized water to obtain a 25wt% guanidine salt polymer aqueous solution.

[0130] SS2: Add 89g of polyethylene glycol diglycidyl ether 400 and 223g of polyethylene glycol monoglycidyl ether 1000 and 936g of deionized water to a reaction vessel, heat to 60℃, stir at 300rpm for 30min to obtain a 25wt% epoxy-terminated polyethylene glycol aqueous solution.

[0131] SS3: The epoxy-terminated polyethylene glycol aqueous solution obtained in SS2 was added dropwise to the guanidine salt polymer aqueous solution in SS1 under stirring at 60℃ and 400rpm. After the addition was completed, the reaction continued for 5h. After cooling to room temperature, 11.2kg of deionized water was added to obtain a 4% two-component spray adhesive flocculant / antibacterial agent.

[0132] The antibacterial test results are shown in Table 1, and the corresponding test plates are shown in Table 1. Figure 1 .

[0133] Comparative Example 1

[0134] Compared with Example 1, the difference is that the flocculant used is a conventional aqueous solution of calcium chloride.

[0135] Synthesis of waterborne acrylic resin:

[0136] S1: Preparation of pre-emulsion: Add 300g deionized water and 10g SDS to the emulsification kettle and stir at 400rpm for 20min until the SDS is completely dissolved. Then add 210g styrene monomer, 500g n-butyl acrylate monomer, 250g isooctyl acrylate monomer, 30g methacrylic acid monomer and 10g diacetone acrylamide mixture to the kettle and stir at 500rpm for 50min to obtain a uniform and stable pre-emulsion. The Tg measured by DSC is -18℃. Set aside for later use.

[0137] S2: Emulsion polymerization reaction: 650g of deionized water and 80g of pre-emulsion were added to the reactor, stirred at 300rpm and heated to 80℃. 3.2g of 5.7% ammonium persulfate aqueous solution was added, and then the temperature was raised to 85℃ and kept at that temperature for 1 hour to obtain the seed emulsion. After the temperature was kept at that temperature, the remaining pre-emulsified monomer was slowly added dropwise while the temperature was maintained at 83℃. At the same time, 49.8g of 5.7% ammonium persulfate aqueous solution was added dropwise at a uniform rate for 5 hours. After the pre-emulsified monomer was added, the temperature was raised to 88℃ and kept at that temperature for 30 minutes. 3g of tert-butyl hydroperoxide and 1g of sodium bisulfite were added to eliminate unreacted monomers.

[0138] S3: Cool to 35℃, add ammonia water to adjust the pH of the emulsion to 5, then add 10g of adipic acid dihydrazide, stir for 30 minutes and filter out the material.

[0139] Preparation of flocculants / antibacterial agents:

[0140] Prepare a 3% aqueous solution of calcium chloride solid.

[0141] The antibacterial test results are shown in Table 1, and the corresponding test plates are shown in Table 1. Figure 1 .

[0142] Comparative Example 2

[0143] Compared with Example 1, the difference is that the flocculant used is a conventional aqueous solution of zinc sulfate.

[0144] Synthesis of waterborne acrylic resin:

[0145] S1: Preparation of pre-emulsion: Add 300g deionized water and 10g SDS to the emulsification kettle and stir at 400rpm for 20min until the SDS is completely dissolved. Then add 210g styrene monomer, 500g n-butyl acrylate monomer, 250g isooctyl acrylate monomer, 30g methacrylic acid monomer and 10g diacetone acrylamide mixture to the kettle and stir at 500rpm for 50min to obtain a uniform and stable pre-emulsion. The Tg measured by DSC is -18℃. Set aside for later use.

[0146] S2: Emulsion polymerization reaction: 650g of deionized water and 80g of pre-emulsion were added to the reactor, stirred at 300rpm and heated to 80℃. 3.2g of 5.7% ammonium persulfate aqueous solution was added, and then the temperature was raised to 85℃ and kept at that temperature for 1 hour to obtain the seed emulsion. After the temperature was kept at that temperature, the remaining pre-emulsified monomer was slowly added dropwise while the temperature was maintained at 83℃. At the same time, 49.8g of 5.7% ammonium persulfate aqueous solution was added dropwise at a uniform rate for 5 hours. After the pre-emulsified monomer was added, the temperature was raised to 88℃ and kept at that temperature for 30 minutes. 3g of tert-butyl hydroperoxide and 1g of sodium bisulfite were added to eliminate unreacted monomers.

[0147] S3: Cool to 35℃, add ammonia water to adjust the pH of the emulsion to 5, then add 10g of adipic acid dihydrazide, stir for 30 minutes and filter out the material.

[0148] Preparation of flocculants / antibacterial agents:

[0149] Prepare an 8% aqueous solution of zinc sulfate solid.

[0150] The antibacterial test results are shown in Table 1, and the corresponding test plates are shown in Table 1. Figure 1 .

[0151] Comparative Example 3

[0152] Compared with Example 1, the difference is that the emulsion used is commercially available chloroprene rubber, and the flocculant used is an aqueous solution of zinc sulfate.

[0153] Preparation of flocculant / antibacterial agent: Prepare an 8% aqueous solution of zinc sulfate solid.

[0154] The antibacterial test results are shown in Table 1, and the corresponding test plates are shown in Table 1. Figure 1 .

[0155] The table below shows the performance test data for the examples and comparative examples:

[0156] Table 1 Performance test data of Examples 1-6 and Comparative Examples 1-3

[0157] Example 1 10:1 0 0 99.9％ Example 2 15:1 0 0 99.9％ Example 3 5:1 0 0 99.9％ Example 4 20:1 0 0 99.9％ Example 5 10:1 0 0 99.9％ Example 6 10:1 0 0 99.9％ Comparative Example 1 10:1 0 0 No antibacterial properties Comparative Example 2 10:1 0 0 No antibacterial properties Comparative Example 3 10:1 0 50 No antibacterial properties

[0158] According to Table 1 and Figure 1 The test data shows that the prepared two-component water-based acrylic spray adhesive has excellent initial tack and better heat resistance than commercially available chloroprene. Using guanidine salt polymer as a flocculant can give it excellent antibacterial properties, with an antibacterial rate of up to 100%, which is of great significance for protecting people's health and avoiding bacterial infections in daily life.

[0159] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features of the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0160] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended patent claims.

Claims

1. A two-component antibacterial water-based acrylic spray adhesive, characterized in that, The adhesive spray includes: Component A: Aqueous acrylic emulsion; Component B is an aqueous solution of a block copolymer obtained by polymerization between guanidine salt polymer and polyethylene glycol; The mass ratio of component A to component B is 5:1 to 20:

1. Among them, the guanidine salt polymer is obtained by adding guanidine salt and polyamine compound into a reaction vessel, heating to prepolymerize, and continuing to heat to react. Wherein, the guanidine salt is one or more of guanidine hydrochloride, metformin hydrochloride, guanidine phosphate, metformin phosphate, guanidine sulfate, and metformin sulfate; The polyamino compound is one or more selected from hexamethylenediamine, pentanediamine, butanediamine, isophoronediamine, N-(2-hydroxyethyl)ethylenediamine, 1,4-diaminocyclohexane, and bis(4-aminocyclohexane)methane; The polyethylene glycol is epoxy-terminated polyethylene glycol.

2. The spray adhesive according to claim 1, characterized in that, The glass transition temperature of the aqueous acrylic emulsion is -40 to 0°C.

3. The spray adhesive according to claim 2, characterized in that, The glass transition temperature of the aqueous acrylic emulsion is -30 to 5°C.

4. The spray adhesive according to claim 1 or 2, characterized in that, The preparation method of the aqueous acrylic emulsion includes the following steps: S1: Add water and emulsifier to the emulsification tank and stir. Continue to add the mixture of polymer monomers, functional monomers and crosslinking monomers and stir to obtain a pre-emulsion. S2: Add water and part of the pre-emulsion to the reactor, stir and heat, add initiator solution, heat and keep warm to obtain seed emulsion; add the remaining pre-emulsion and keep warm, add initiator solution, heat and keep warm after addition, and after the reaction is completed, add post-treatment agent to eliminate unreacted monomers. S3: Cool down, add pH adjuster, add adipic acid dihydrazide, stir and filter out the material.

5. The spray adhesive according to claim 4, characterized in that, The emulsifier in S1 is selected from one or more of sodium dodecyl sulfate (SDS), sodium tridecyl alcohol polyoxyethylene ether sulfate (CM-30), and sodium alkyl polyethylene glycol ether sulfate (EPA-073); And / or, the polymer monomer in S1 is selected from (meth)acrylate monomers or mixtures of (meth)acrylate monomers and vinyl monomers; wherein, the (meth)acrylate monomer is selected from one or more of alkyl (meth)acrylates with 1-20 carbon atoms in the alkyl chain; the vinyl monomer is selected from one or more of vinyl esters of carboxylic acids containing ≤20 carbon atoms and vinyl aromatic compounds containing ≤20 carbon atoms; the vinyl ester of carboxylic acids containing ≤20 carbon atoms is one or more of vinyl acetate, vinyl propionate, vinyl laurate or vinyl stearate; the vinyl aromatic compound containing ≤20 carbon atoms is selected from one or more of styrene and vinyltoluene; And / or, the functional monomer of S1 is selected from one or more olefinic unsaturated monomers containing carboxyl, sulfonic acid, hydroxyl or amide functional groups; And / or, the crosslinking monomer in S1 is diacetone acrylamide; And / or, the first stirring time in S1 is 20-60 min, and the second stirring time is 50-120 min.

6. The spray adhesive according to claim 5, characterized in that, The emulsifier in S1 is SDS; The emulsifier is used at a rate of 0.6-1.5% of the total mass of the monomer mixture; And / or, the (meth)acrylate monomers described in S1 are selected from one or more of methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, cyclohexyl (meth)acrylate, isooctyl (meth)acrylate, dodecyl (meth)acrylate, and octadecyl (meth)acrylate. The polymer monomer is used in an amount that accounts for 90%-99.8% of the total mass of the monomer mixture; And / or, the carboxyl-containing olefinic unsaturated monomer in S1 is one or more of acrylic acid, methacrylic acid, maleic acid, and itaconic acid; the sulfonic acid-containing olefinic unsaturated monomer is one or more of sodium p-styrene sulfonate, sodium vinyl sulfonate, and sodium allyl ether hydroxypropyl sulfonate; the hydroxyl-containing olefinic unsaturated monomer is one or more of hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxyethyl acrylate, and hydroxypropyl acrylate; and the amide-containing olefinic unsaturated monomer is acrylamide. The functional monomer is used in an amount of 0.1%-5% of the total mass of the monomer mixture; The crosslinking monomers described in S1 account for 0.1%-5% of the total mass of the total monomer mixture.

7. The spray adhesive according to claim 6, characterized in that, The (meth)acrylate monomer described in S1 is selected from one or more of methyl methacrylate, methyl acrylate, n-butyl acrylate, and isooctyl acrylate.

8. The spray adhesive according to claim 4, characterized in that, The initiator described in S2 is a thermally initiating initiator and / or a redox initiator; wherein the redox initiator is composed of an oxidizing agent and a reducing agent; And / or, the portion of pre-emulsion added in S2 accounts for 5%-15% of the total emulsion mass; And / or, after adding S2 to the initiator solution, raise the temperature to 83-85℃, and after the pre-emulsion is completely added, raise the temperature to 85-88℃ and keep warm for 20-40 minutes.

9. The spray adhesive according to claim 8, characterized in that, In S2, the thermal initiator is one or more of ammonium persulfate, potassium persulfate, sodium persulfate, tert-butyl hydroperoxide, hydrogen peroxide, benzoyl peroxide (BPO), and azobisisobutyronitrile (AIBN); the oxidant in the redox initiator is one or more of ammonium persulfate, potassium persulfate, sodium persulfate, tert-butyl hydroperoxide, hydrogen peroxide, and BPO; and the reducing agent is one or more of sodium sulfite, sodium bisulfite, sodium formaldehyde sulfoxylate, and ascorbic acid. The initiator is used in an amount of 0.2-0.5% of the total mass of the monomer mixture; And / or, the portion of pre-emulsion added in S2 accounts for 6-10% of the total mass of the emulsion.

10. The spray adhesive according to claim 9, characterized in that, The amount of the initiator described in S2 is 0.3-0.4% of the total mass of the monomer mixture.

11. The spray adhesive according to claim 4, characterized in that, The pH adjuster mentioned in S3 is one or more of sodium hydroxide, potassium hydroxide, ammonia, ethanolamine, and triethylamine; And / or, after adding S3 to adipic dihydrazide, stir for 20-40 minutes.

12. The spray adhesive according to claim 1, characterized in that, The method for preparing the aqueous solution of component B guanidine salt polymer and polyethylene glycol block copolymer includes the following steps: SS1: Add guanidine salt and polyamine compound to the reactor, heat to prepolymerize, continue heating to react, cool down and add water to prepare guanidine salt polymer aqueous solution; SS2: Add water and epoxy-terminated polyethylene glycol to the reactor, heat and stir until the epoxy-terminated polyethylene glycol dissolves to obtain an aqueous solution of epoxy-terminated polyethylene glycol; SS3: Add an aqueous solution of epoxy-terminated polyethylene glycol to an aqueous solution of guanidine salt polymer to carry out the polymerization reaction, and dilute the aqueous solution of the reaction product.

13. The spray adhesive according to claim 12, characterized in that, The molar ratio of the guanidine salt to the polyamino compound in SS1 is 1:(1.05-1.3); And / or, the SS1 is first heated to 110-130℃ and reacted for 1-2 hours, and then heated to 140-160℃ and reacted for 3-4 hours; And / or, the concentration of the guanidine salt polymer aqueous solution in SS1 is 20-30 wt%.

14. The spray adhesive according to claim 12, characterized in that, The guanidine salt in SS1 is guanidine hydrochloride.

15. The spray adhesive according to claim 13, characterized in that, The molar ratio of the guanidine salt to the polyamino compound described in SS1 is 1:(1.1-1.2).

16. The spray adhesive according to claim 12, characterized in that, The polyamino compound mentioned in SS1 is hexamethylenediamine.

17. The spray adhesive according to claim 12, characterized in that, In SS2, the epoxy-terminated polyethylene glycol is polyethylene glycol diglycidyl ether and / or polyethylene glycol monoglycidyl ether; And / or, the SS2 is heated to 50-60°C; And / or, the concentration of the epoxy-terminated polyethylene glycol aqueous solution described in SS2 is 20-30 wt%.

18. The spray adhesive according to claim 17, characterized in that, The molecular weight of the epoxy-terminated polyethylene glycol described in SS2 is 200-6000.

19. The spray adhesive according to claim 18, characterized in that, The molecular weight of the epoxy-terminated polyethylene glycol described in SS2 is 400-2000.

20. The spray adhesive according to claim 12, characterized in that, The mass ratio of guanidine salt polymer to epoxy-terminated polyethylene glycol in SS3 is 1:(1-6); And / or, the concentration of the aqueous solution of the reaction product in SS3 is 1-10%; And / or, the SS3 temperature is 50-80℃, and the reaction time is 4-6h.

21. The spray adhesive according to claim 20, characterized in that, The mass ratio of guanidine salt polymer to epoxy-terminated polyethylene glycol in SS3 is 1:(2-4); And / or, the concentration of the aqueous solution of the reaction product in SS3 is 2-7%.

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