阅读说明：本技术 一种pvc用抗菌乳液及其制备方法 (Antibacterial emulsion for PVC and preparation method thereof ) 是由 李丹丹 于 2020-11-18 设计创作，主要内容包括：本发明属于高分子材料领域,具体涉及一种PVC用抗菌乳液及其制备方法,该抗菌乳液包括以下重量份数的原料：总单体35-50份、乳化剂1-3份、pH缓冲剂0.5-1份、引发剂0.05-0.3份、去离子水50-65份,并经带温带压反应得到抗菌乳液。本发明产品有效改善现有技术中水性氯乙烯共聚乳液耐水性差、不抗菌等不足,兼顾综合性能,解决了问题的同时,具有高效耐候性等性能。可以预见,该材料将在工业涂料、建筑涂料等室内、户外使用迎来广阔的市场前景,尤其适用PVC薄膜(食品包装等)、PVC地板涂层等领域等。(The invention belongs to the field of high polymer materials, and particularly relates to an antibacterial emulsion for PVC (polyvinyl chloride) and a preparation method thereof, wherein the antibacterial emulsion comprises the following raw materials in parts by weight: 35-50 parts of total monomers, 1-3 parts of emulsifier, 0.5-1 part of pH buffer, 0.05-0.3 part of initiator and 50-65 parts of deionized water, and carrying out a warm-pressing reaction to obtain the antibacterial emulsion. The product of the invention effectively overcomes the defects of poor water resistance, no antibiosis and the like of the aqueous vinyl chloride copolymer emulsion in the prior art, gives consideration to the comprehensive performance, solves the problems and has the performances of high efficiency, weather resistance and the like. The material can be expected to have wide market prospect in indoor and outdoor use such as industrial coating, building coating and the like, and is particularly suitable for the fields such as PVC films (food packaging and the like), PVC floor coatings and the like.)

1. An antibacterial emulsion for PVC, which is characterized in that: the composite material comprises the following raw materials in parts by weight:

35-50 parts of total monomers, 1-3 parts of emulsifier, 0.5-1 part of pH buffer, 0.05-0.3 part of initiator and 50-65 parts of deionized water;

the total monomers comprise vinyl chloride monomers, acrylate monomers and functional monomers.

2. The antibacterial emulsion for PVC according to claim 1, characterized in that: the vinyl chloride monomer is chloroethylene, chlorovinylidene chloride, chlorotrifluoroethylene or a mixture thereof.

3. The antibacterial emulsion for PVC according to claim 1, characterized in that: the acrylate monomers are selected from methyl (meth) acrylate, butyl acrylate, isooctyl acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate or glycidyl methacrylate.

4. The antibacterial emulsion for PVC according to claim 1, characterized in that: the functional monomer is acrylic acid, styrene, ethylene versatate or a mixture thereof.

5. The antibacterial emulsion for PVC according to claim 1, characterized in that: the emulsifier is quaternary ammonium salt alkyl polyoxyethylene maleic diester or nonylphenol polyoxyethylene ether.

6. A preparation method of antibacterial emulsion for PVC is characterized by comprising the following steps: the method specifically comprises the following specific steps:

(1) weighing liquid phase total monomers and 0.5-2 parts of emulsifier, putting into a pre-emulsification kettle, and stirring and emulsifying for 30min under the condition that the stirring speed is not lower than 200r/min to obtain a pre-emulsification monomer solution;

(2) taking 20-35 parts of deionized water, 0.5-1 part of pH buffering agent and 0.05-0.3 part of initiator, fully stirring and dissolving, and then adding into the pre-emulsification kettle in the step (1);

(3) reaction: adding the gas-phase total monomers, the rest of the emulsifier and the rest of the deionized water into a vacuum kettle according to the volume, and homogenizing for 30min under a high-speed stirring state; then putting the pre-emulsified monomer 1/6-1/5 obtained in the step (1) into a polymerization kettle, stirring for 30min, and heating to 70-80 ℃; adding the initiator 1/5-1/4 dissolved in the step (2) to start polymerization, continuously adding the rest pre-emulsified monomer and the initiator when the pressure of the polymerization kettle is reduced from the initial pressure to 0.2MPa, completing the addition within 4-6 hours, raising the reaction temperature to 80 +/-1 ℃, and continuing the reaction until the reaction pressure of the polymerization kettle is lower than 0.1 MPa; cooling to below 40 ℃, vacuumizing to below 0.09MPa, recovering unreacted gas-phase monomers, stopping the vacuum pump, discharging, filtering and packaging to obtain the target product.

Technical Field

The invention belongs to the field of high polymer materials, and particularly relates to an antibacterial emulsion for PVC and a preparation method thereof.

Background

Chlorine-containing polymers such as vinyl chloride-vinyl acetate copolymer, vinyl chloride-isobutyl vinyl ether copolymer, chlorosulfonated polyethylene, etc. are important matrix resins for preparing anticorrosive coatings, and the properties thereof are closely related to the chlorine content of the polymers. At present, chlorine-containing polymers are mainly dissolved in organic solvents (solvents such as aromatic hydrocarbon, ketone or ester) to prepare coatings, printing ink and the like, and although the chlorine-containing polymers have the advantages of fast film formation, good film compactness and the like, the chlorine-containing polymers are high in Volatile Organic Compound (VOC) content and are not friendly to the environment, so that the development of the chlorine-containing polymers is restricted. The water-based coating is one of the main trends in the development of coatings.

Emulsifiers play an important role in the way of watery cosmetics. Non-reactive emulsifiers are commonly used, and are used by means of physical addition. The method has the defects of easy migration, non-lasting effect, environmental pollution, harm to human health and the like, and has certain defects of decoration, water mark after rain and the like no matter the stability of the emulsion, such as mechanical stability, electrolyte stability and the like, or the formed film. But also greatly influences the safety use performance, water resistance and other performances. In addition, a problem has been posed to the developers of aqueous resins, which have been problematic in terms of water resistance after film formation because aqueous resins, including aqueous vinyl chloride copolymer emulsions, are prepared in an aqueous phase.

On the other hand, with the scientific and technological progress, social development and improvement of living standard of people, living environment is required to be more environment-friendly, healthy and safe, and great demand is generated on antibacterial coating.

In view of the above situation, in combination with the low cost of vinyl chloride, the development of a novel antibacterial emulsion of vinyl chloride is urgent.

Disclosure of Invention

The invention aims to provide an antibacterial emulsion for PVC and a preparation method thereof, aiming at the defects of poor water resistance, no antibacterial property and the like of the water-based vinyl chloride copolymer emulsion in the prior art. By means of the design of a synthetic formula, the coating solves the problems and has the performances of high efficiency, weather resistance and the like. It is expected that the material will be used in indoor and outdoor occasions such as industrial coating, building coating and the like, and is particularly suitable for the fields such as PVC film (food packaging and the like), PVC floor coating and the like.

In order to achieve the purpose, the technical scheme adopted by the invention for solving the technical problems is as follows:

an antibacterial emulsion for PVC, which is characterized in that: the composite material comprises the following raw materials in parts by weight:

35-50 parts of total monomers, 1-3 parts of emulsifier, 0.5-1 part of pH buffer, 0.05-0.3 part of initiator and 50-65 parts of deionized water;

the total monomers comprise vinyl chloride monomers, acrylate monomers and functional monomers.

Preferably, the vinyl chloride-based monomer is vinyl chloride, polyvinylidene chloride, chlorotrifluoroethylene, or a mixture thereof.

Preferably, the acrylate monomer is selected from methyl (meth) acrylate, butyl acrylate, isooctyl acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate or glycidyl methacrylate.

Preferably, the functional monomer is acrylic acid, styrene, vinyl versatate or a mixture thereof.

Preferably, the emulsifier is quaternary ammonium alkyl polyoxyethylene maleic diester or nonylphenol polyoxyethylene ether.

A preparation method of antibacterial emulsion for PVC specifically comprises the following specific steps:

(1) weighing liquid phase total monomers and 0.5-2 parts of emulsifier, putting into a pre-emulsification kettle, and stirring and emulsifying for 30min under the condition that the stirring speed is not lower than 200r/min to obtain a pre-emulsification monomer solution;

(2) taking 20-35 parts of deionized water, 0.5-1 part of pH buffering agent and 0.05-0.3 part of initiator, fully stirring and dissolving, and then adding into the pre-emulsification kettle in the step (1);

(3) reaction: adding the gas-phase total monomers, the rest of the emulsifier and the rest of the deionized water into a vacuum kettle according to the volume, and homogenizing for 30min under a high-speed stirring state; then putting the pre-emulsified monomer 1/6-1/5 obtained in the step (1) into a polymerization kettle, stirring for 30min, heating to 70-80 ℃, adding the initiator 1/5-1/4 dissolved in the step (2) to start polymerization, continuously supplementing the rest of the pre-emulsified monomer and the initiator when the pressure of the polymerization kettle is reduced from the initial pressure to 0.2MPa, completing the supplementation within 4-6 hours, heating the reaction temperature to 80 +/-1 ℃, and continuing the reaction until the reaction pressure of the polymerization kettle is lower than 0.1 MPa; cooling to below 40 ℃, vacuumizing to below 0.09MPa, recovering unreacted gas-phase monomers, stopping the vacuum pump, discharging, filtering and packaging to obtain the target product.

The invention has the following beneficial effects:

(1) the invention provides an antibacterial emulsion for PVC, which contains chloroethylene in the structure, and on one hand, halogen has high-efficiency flame retardant property; on the other hand, the strong polar group is favorable for adhesion on the surface of the base material and has excellent adhesion.

(2) The invention provides an antibacterial emulsion for PVC, which contains a-C-F bond and a tertiary ethylene carbonate structure, and not only can provide good water resistance, but also has excellent weather resistance.

(3) The invention provides an antibacterial emulsion for PVC, which uses a reactive quaternary ammonium salt emulsifier, firstly, the reactive emulsifier can be connected into a system in a chemical bond form without migration and precipitation, and the coating performance is better; second, quaternary ammonium salt systems have excellent broad spectrum antibacterial properties.

(4) The invention provides an antibacterial emulsion for PVC, which overcomes the defects of poor water resistance, no antibacterial property and the like of the traditional water-based vinyl chloride copolymer emulsion and has the performances of high efficiency, weather resistance and the like through the formula design. The material can be expected to have wide market prospect in indoor and outdoor use such as industrial coating, building coating and the like, and is particularly suitable for the fields such as PVC films (food packaging and the like), PVC floor coatings and the like.

The specific implementation mode is as follows:

the present invention will be described in detail with reference to examples. It is to be understood, however, that the following examples are illustrative of embodiments of the present invention and are not to be construed as limiting the scope of the invention.

Example 1

An antibacterial emulsion for PVC comprises the following raw materials in parts by weight:

35 parts of total monomers: 10.5 parts of chloroethylene, 7 parts of chlorotrifluoroethylene, 2.8 parts of butyl acrylate, 4.2 parts of isooctyl acrylate, 2.8 parts of hydroxyethyl acrylate, 1.4 parts of glycidyl methacrylate, 1.4 parts of styrene and 4.9 parts of vinyl versatate;

emulsifier: 1 part of quaternary ammonium salt octadecyl polyoxyethylene maleic diester (n ═ 10);

PH buffer: 0.5 part of sodium hydrogen phosphate;

initiator: 0.05 part of potassium persulfate;

65 parts of deionized water.

A preparation method of antibacterial emulsion for PVC specifically comprises the following specific steps:

(1) weighing liquid phase total monomers and 0.5 part of emulsifier, putting into a pre-emulsification kettle, and stirring and emulsifying for 30min under the condition that the stirring speed is not lower than 200r/min to obtain a pre-emulsification monomer solution;

(2) taking 35 parts of deionized water, 0.5 part of pH buffering agent and 0.05 part of initiator, fully stirring and dissolving, and then adding into the pre-emulsification kettle in the step (1);

(3) reaction: adding the gas-phase total monomers, the rest of the emulsifier and the rest of the deionized water into a vacuum kettle according to the volume, and homogenizing for 30min under a high-speed stirring state; then, taking the pre-emulsified monomer 1/6 obtained in the step (1) into a polymerization kettle, stirring for 30min, and heating to 70-80 ℃; adding the initiator 1/5 dissolved in the step (2) to start a polymerization reaction, continuously adding the rest pre-emulsified monomer and the initiator when the pressure of the polymerization kettle is reduced by 0.2MPa from the initial pressure, finishing the addition within 4 hours, raising the reaction temperature to 80 +/-1 ℃, and continuing the reaction until the reaction pressure of the polymerization kettle is lower than 0.1 MPa; cooling to below 40 ℃, vacuumizing to below 0.09MPa, recovering unreacted chloroethylene, stopping the vacuum pump, discharging, filtering and packaging to obtain the target product.

Example 2

An antibacterial emulsion for PVC comprises the following raw materials in parts by weight:

50 parts of total monomers: 9.5 parts of chloroethylene, 11.5 parts of vinylidene chloride, 9 parts of chlorotrifluoroethylene, 2.5 parts of methyl acrylate, 7.5 parts of isooctyl acrylate, 5 parts of hydroxyethyl acrylate, 1 part of styrene and 4 parts of vinyl versatate;

emulsifier: 2 parts of quaternary ammonium salt nonylphenol polyoxyethylene maleic diester (n ═ 10) and 1 part of nonylphenol polyoxyethylene ether;

PH buffer: 1 part of sodium hydrogen phosphate;

initiator: 0.3 part of potassium persulfate;

50 parts of deionized water.

A preparation method of antibacterial emulsion for PVC specifically comprises the following specific steps:

(1) weighing liquid-phase total monomers and 2 parts of emulsifier, putting into a pre-emulsification kettle, and stirring and emulsifying for 30min under the condition that the stirring speed is not lower than 200r/min to obtain a pre-emulsification monomer solution;

(2) adding 20 parts of deionized water, 1 part of pH buffering agent and 0.3 part of initiator into the pre-emulsification kettle in the step (1) after fully stirring and dissolving;

(3) reaction: adding the gas-phase total monomers, the rest of the emulsifier and the rest of the deionized water into a vacuum kettle according to the volume, and homogenizing for 30min under a high-speed stirring state; then putting the pre-emulsified monomer 1/5 obtained in the step (1) into a polymerization kettle, stirring for 30min, and then heating to 80 ℃; adding the initiator 1/4 dissolved in the step (2) to start a polymerization reaction, continuously adding the rest pre-emulsified monomer and the initiator when the pressure of the polymerization kettle is reduced from the initial pressure to 0.2MPa, finishing the addition within 6 hours, raising the reaction temperature to 80 +/-1 ℃, and continuously reacting until the reaction pressure of the polymerization kettle is lower than 0.1 MPa; cooling to below 40 ℃, vacuumizing to below 0.09MPa, recovering unreacted chloroethylene, stopping the vacuum pump, discharging, filtering and packaging to obtain the target product.

Example 3

An antibacterial emulsion for PVC comprises the following raw materials in parts by weight:

40 parts of total monomers: 6 parts of vinyl chloride, 12 parts of vinylidene chloride, 6 parts of chlorotrifluoroethylene, 4 parts of butyl acrylate, 4 parts of isooctyl acrylate, 4 parts of hydroxypropyl acrylate, 0.4 part of acrylic acid and 3.6 parts of vinyl versatate;

emulsifier: 2 parts of quaternary ammonium salt dodecyl polyoxyethylene maleic diester (n ═ 20);

PH buffer: 0.8 part of sodium hydrogen phosphate;

initiator: 0.2 part of potassium persulfate;

60 parts of deionized water.

A preparation method of antibacterial emulsion for PVC specifically comprises the following specific steps:

(1) weighing liquid-phase total monomers and 1 part of emulsifier, putting into a pre-emulsification kettle, and stirring and emulsifying for 30min under the condition that the stirring speed is not lower than 200r/min to obtain a pre-emulsification monomer solution;

(2) adding 30 parts of deionized water, 0.8 part of pH buffering agent and 0.2 part of initiator into the pre-emulsification kettle in the step (1) after fully stirring and dissolving;

(3) reaction: adding the gas-phase total monomers, the rest of the emulsifier and the rest of the deionized water into a vacuum kettle according to the volume, and homogenizing for 30min under a high-speed stirring state; then putting the pre-emulsified monomer 1/6 obtained in the step (1) into a polymerization kettle, stirring for 30min, and then heating to 70 ℃; adding the initiator 1/5 dissolved in the step (2) to start a polymerization reaction, continuously adding the rest pre-emulsified monomer and the initiator when the pressure of the polymerization kettle is reduced from the initial pressure to 0.2MPa, finishing the addition within 5 hours, raising the reaction temperature to 80 +/-1 ℃, and continuously reacting until the reaction pressure of the polymerization kettle is lower than 0.1 MPa; cooling to below 40 ℃, vacuumizing to below 0.09MPa, recovering unreacted chloroethylene, stopping the vacuum pump, discharging, filtering and packaging to obtain the target product.

Example 4

An antibacterial emulsion for PVC comprises the following raw materials in parts by weight:

50 parts of total monomers: 12.5 parts of chloroethylene, 12.5 parts of chlorotrifluoroethylene, 6.5 parts of methyl methacrylate, 8.5 parts of isooctyl acrylate, 2.5 parts of glycidyl methacrylate, 3.5 parts of styrene and 4 parts of vinyl versatate;

emulsifier: 3 parts of quaternary ammonium salt nonyl phenol polyoxyethylene maleic diester (n ═ 20);

PH buffer: 0.5 part of sodium hydrogen phosphate;

initiator: 0.1 part of potassium persulfate;

50 parts of deionized water.

A preparation method of antibacterial emulsion for PVC specifically comprises the following specific steps:

(1) weighing liquid-phase total monomers and 2 parts of emulsifier, putting into a pre-emulsification kettle, and stirring and emulsifying for 30min under the condition that the stirring speed is not lower than 200r/min to obtain a pre-emulsification monomer solution;

(2) taking 20 parts of deionized water, 0.5 part of pH buffering agent and 0.1 part of initiator, fully stirring and dissolving, and then adding into the pre-emulsification kettle in the step (1);

(3) reaction: adding the gas-phase total monomers, the rest of the emulsifier and the rest of the deionized water into a vacuum kettle according to the volume, and homogenizing for 30min under a high-speed stirring state; then putting the pre-emulsified monomer 1/5 obtained in the step (1) into a polymerization kettle, stirring for 30min, and heating to 75 ℃; adding the initiator 1/4 dissolved in the step (2) to start a polymerization reaction, continuously adding the rest pre-emulsified monomer and the initiator when the pressure of the polymerization kettle is reduced from the initial pressure to 0.2MPa, finishing the addition within 6 hours, raising the reaction temperature to 80 +/-1 ℃, and continuously reacting until the reaction pressure of the polymerization kettle is lower than 0.1 MPa; cooling to below 40 ℃, vacuumizing to below 0.09MPa, recovering unreacted chloroethylene, stopping the vacuum pump, discharging, filtering and packaging to obtain the target product.

Example 5

An antibacterial emulsion for PVC comprises the following raw materials in parts by weight:

45 parts of total monomers: 9.9 parts of vinyl chloride, 7.65 parts of vinylidene chloride, 7.2 parts of chlorotrifluoroethylene, 4.95 parts of butyl acrylate, 2.25 parts of isooctyl acrylate, 5.4 parts of hydroxypropyl acrylate, 0.9 part of glycidyl methacrylate and 6.75 parts of vinyl versatate;

emulsifier: 2 parts of quaternary ammonium salt dodecyl polyoxyethylene maleic diester (n is 10);

PH buffer: 0.7 part of sodium hydrogen phosphate;

initiator: 0.2 part of potassium persulfate;

and 55 parts of deionized water.

A preparation method of antibacterial emulsion for PVC specifically comprises the following specific steps:

(1) weighing liquid-phase total monomers and 1 part of emulsifier, putting into a pre-emulsification kettle, and stirring and emulsifying for 30min under the condition that the stirring speed is not lower than 200r/min to obtain a pre-emulsification monomer solution;

(2) adding 25 parts of deionized water, 0.7 part of pH buffering agent and 0.2 part of initiator into the pre-emulsification kettle in the step (1) after fully stirring and dissolving;

(3) reaction: adding the gas-phase total monomers, the rest of the emulsifier and the rest of the deionized water into a vacuum kettle according to the volume, and homogenizing for 30min under a high-speed stirring state; then putting the pre-emulsified monomer 1/5 obtained in the step (1) into a polymerization kettle, stirring for 30min, and then heating to 80 ℃; adding the initiator 1/4 dissolved in the step (2) to start a polymerization reaction, continuously adding the rest pre-emulsified monomer and the initiator when the pressure of the polymerization kettle is reduced from the initial pressure to 0.2MPa, finishing the addition within 5 hours, raising the reaction temperature to 80 +/-1 ℃, and continuously reacting until the reaction pressure of the polymerization kettle is lower than 0.1 MPa; cooling to below 40 ℃, vacuumizing to below 0.09MPa, recovering unreacted chloroethylene, stopping the vacuum pump, discharging, filtering and packaging to obtain the target product.

Examples comparative examples 1-3 are all compared to the antimicrobial emulsion of example 1:

comparative example 1 was carried out

An antibacterial emulsion for PVC comprises the following raw materials in parts by weight:

35 parts of total monomers: 17.5 parts of chloroethylene, 2.8 parts of butyl acrylate, 4.2 parts of isooctyl acrylate, 2.8 parts of hydroxyethyl acrylate, 1.4 parts of glycidyl methacrylate and 6.3 parts of styrene;

emulsifier: 1 part of sodium dodecyl benzene sulfonate;

PH buffer: 0.5 part of sodium hydrogen phosphate;

initiator: 0.05 part of potassium persulfate;

65 parts of deionized water.

A preparation method of antibacterial emulsion for PVC specifically comprises the following specific steps:

(1) weighing liquid phase total monomers and 0.5 part of emulsifier, putting into a pre-emulsification kettle, and stirring and emulsifying for 30min under the condition that the stirring speed is not lower than 200r/min to obtain a pre-emulsification monomer solution;

(2) taking 35 parts of deionized water, 0.5 part of pH buffering agent and 0.05 part of initiator, fully stirring and dissolving, and then adding into the pre-emulsification kettle in the step (1);

(3) reaction: adding the gas-phase total monomers, the rest of the emulsifier and the rest of the deionized water into a vacuum kettle according to the volume, and homogenizing for 30min under a high-speed stirring state; then, taking the pre-emulsified monomer 1/6 obtained in the step (1) into a polymerization kettle, stirring for 30min, and heating to 70-80 ℃; adding the initiator 1/5 dissolved in the step (2) to start a polymerization reaction, continuously adding the rest pre-emulsified monomer and the initiator when the pressure of the polymerization kettle is reduced by 0.2MPa from the initial pressure, finishing the addition within 4 hours, raising the reaction temperature to 80 +/-1 ℃, and continuing the reaction until the reaction pressure of the polymerization kettle is lower than 0.1 MPa; cooling to below 40 ℃, vacuumizing to below 0.09MPa, recovering unreacted chloroethylene, stopping the vacuum pump, discharging, filtering and packaging to obtain the target product.

Comparative example 2 was carried out

An antibacterial emulsion for PVC comprises the following raw materials in parts by weight:

35 parts of total monomers: 10.5 parts of chloroethylene, 7 parts of chlorotrifluoroethylene, 2.8 parts of butyl acrylate, 4.2 parts of isooctyl acrylate, 2.8 parts of hydroxyethyl acrylate, 1.4 parts of glycidyl methacrylate and 6.3 parts of styrene;

emulsifier: 1 part of sodium dodecyl benzene sulfonate;

PH buffer: 0.5 part of sodium hydrogen phosphate;

initiator: 0.05 part of potassium persulfate;

65 parts of deionized water.

A preparation method of antibacterial emulsion for PVC specifically comprises the following specific steps:

(1) weighing liquid phase total monomers and 0.5 part of emulsifier, putting into a pre-emulsification kettle, and stirring and emulsifying for 30min under the condition that the stirring speed is not lower than 200r/min to obtain a pre-emulsification monomer solution;

(2) taking 35 parts of deionized water, 0.5 part of pH buffering agent and 0.05 part of initiator, fully stirring and dissolving, and then adding into the pre-emulsification kettle in the step (1);

(3) reaction: adding the gas-phase total monomers, the rest of the emulsifier and the rest of the deionized water into a vacuum kettle according to the volume, and homogenizing for 30min under a high-speed stirring state; then, taking the pre-emulsified monomer 1/6 obtained in the step (1) into a polymerization kettle, stirring for 30min, and heating to 70-80 ℃; adding the initiator 1/5 dissolved in the step (2) to start a polymerization reaction, continuously adding the rest pre-emulsified monomer and the initiator when the pressure of the polymerization kettle is reduced by 0.2MPa from the initial pressure, finishing the addition within 4 hours, raising the reaction temperature to 80 +/-1 ℃, and continuing the reaction until the reaction pressure of the polymerization kettle is lower than 0.1 MPa; cooling to below 40 ℃, vacuumizing to below 0.09MPa, recovering unreacted chloroethylene, stopping the vacuum pump, discharging, filtering and packaging to obtain the target product.

Comparative example 3 was carried out

An antibacterial emulsion for PVC comprises the following raw materials in parts by weight:

35 parts of total monomers: 10.5 parts of chloroethylene, 7 parts of chlorotrifluoroethylene, 2.8 parts of butyl acrylate, 4.2 parts of isooctyl acrylate, 2.8 parts of hydroxyethyl acrylate, 1.4 parts of glycidyl methacrylate, 1.4 parts of styrene and 4.9 parts of vinyl versatate;

emulsifier: 1 part of sodium dodecyl benzene sulfonate;

PH buffer: 0.5 part of sodium hydrogen phosphate;

initiator: 0.05 part of potassium persulfate;

65 parts of deionized water.

A preparation method of antibacterial emulsion for PVC specifically comprises the following specific steps:

(1) weighing liquid phase total monomers and 0.5 part of emulsifier, putting into a pre-emulsification kettle, and stirring and emulsifying for 30min under the condition that the stirring speed is not lower than 200r/min to obtain a pre-emulsification monomer solution;

(2) taking 35 parts of deionized water, 0.5 part of pH buffering agent and 0.05 part of initiator, fully stirring and dissolving, and then adding into the pre-emulsification kettle in the step (1);

(3) reaction: adding the gas-phase total monomers, the rest of the emulsifier and the rest of the deionized water into a vacuum kettle according to the volume, and homogenizing for 30min under a high-speed stirring state; then, taking the pre-emulsified monomer 1/6 obtained in the step (1) into a polymerization kettle, stirring for 30min, and heating to 70-80 ℃; adding the initiator 1/5 dissolved in the step (2) to start a polymerization reaction, continuously adding the rest pre-emulsified monomer and the initiator when the pressure of the polymerization kettle is reduced by 0.2MPa from the initial pressure, finishing the addition within 4 hours, raising the reaction temperature to 80 +/-1 ℃, and continuing the reaction until the reaction pressure of the polymerization kettle is lower than 0.1 MPa; cooling to below 40 ℃, vacuumizing to below 0.09MPa, recovering unreacted chloroethylene, stopping the vacuum pump, discharging, filtering and packaging to obtain the target product.

The antibacterial emulsions prepared in the examples 1-5 and the comparative examples 1-3 are diluted according to the construction requirements, coated on a PVC film, and air-dried at room temperature to obtain a dry film 10um coating.

Physical properties including hardness, adhesion, boiling resistance, water resistance, flame retardancy, weather resistance and antibacterial property of the antibacterial coatings prepared in examples 1 to 5 of the present invention and comparative examples 1 to 3 were measured, respectively, and the results are shown in table 1.

Table 1 physical test properties of the examples

Firstly, as can be seen from table 1, the antibacterial coating prepared from the antibacterial emulsion of the present invention has excellent adhesion when coated on a PVC material, and also has excellent water resistance;

secondly, the antibacterial coating prepared from the antibacterial emulsion has better functionality, especially water resistance and weather resistance;

thirdly, the antibacterial coating prepared from the antibacterial emulsion has excellent antibacterial effect.

In summary, compared with the prior art, the antibacterial emulsion of the invention not only overcomes the defects of poor water resistance, no antibacterial property and the like of the aqueous vinyl chloride copolymer emulsion in the prior art, but also has the performances of high efficiency, weather resistance and the like under the condition of no change of other performances, and can be expected to have wide market prospects in indoor and outdoor use of industrial coatings, building coatings and the like, and is particularly suitable for the fields of PVC films (food packaging and the like), PVC floor coatings and the like.

The test method comprises the following steps:

(1) hardness: and (3) scribing 5 lines with 500g of force on the surface of the film to be detected by using a Mitsubishi pencil, wherein each line is about 5mm, and the pen point needs to be ground flat once. The surface is not scratched after the eraser is used for erasing. Taking 3 times of no scratch as a pass for 5 times, and marking as OK; otherwise, it is denoted as NG.

(2) Adhesion force: the test is carried out with reference to the GB/T9286-88 standard.

(3) Boiling in water: and (3) placing the PVC coating in boiling water for 2h, taking out and re-testing the adhesive force.

(4) Water resistance: after the emulsion was filmed on a glass plate at room temperature for 24 hours, it was carefully removed and cut into flakes having a size of 2.5cm × 2.5cm, and vacuum-dried at 40 ℃ for 24 hours. After the original quality of the film is determined, the film is immersed in deionized water, and the water absorption condition of the film at different time points is tested. After the film is taken out each time, the moisture on the surface of the film needs to be adsorbed by filter paper, and then the film quality is measured. Water resistance expression method: 5 is optimal and 1 is worst.

(5) Flame retardancy: visual observation, expression method: 5 is optimal and 1 is worst.

(6) Weather resistance: placing the film outdoors for the same number of days, observing the surface state and testing the water contact angle; weather resistance means, 5 is optimal and 1 is worst.

(7) And (3) antibacterial property: evaluation was made based on the antibacterial property measurement method and antibacterial effect (GB 21866-2008) of the antibacterial coating (paint film).

In light of the foregoing description of the preferred embodiment of the present invention, many modifications and variations will be apparent to those skilled in the art without departing from the spirit and scope of the invention. The technical scope of the present invention is not limited to the content of the specification, and must be determined according to the scope of the claims.