阅读说明：本技术 一种防水涂料及其制备方法 (Waterproof coating and preparation method thereof ) 是由 王斌 董峰亮 宋丹 黄仲周 吴靖 张利民 张赢 李文杰 于 2020-07-09 设计创作，主要内容包括：一种防水涂料,按重量百分比包括：防水涂料：特种高聚物乳液75％～85％；憎水剂0.5％～1.5％；消泡剂0.1％～0.5％；增稠剂0.1％～0.5％；偶联剂0.5～1.0％；杀菌剂0.1％～0.5％；水15％～25％；其中,特种高聚物乳液包括：丙烯酸丁酯15％～25％；甲基丙烯酸甲酯8％～20％；苯乙烯8％～20％；甲基丙烯酸0.2％～1.0％；丙烯酰胺0.1％～0.5％；有机硅单体0.5％～2％；复合乳化剂0.5％～2％；缓冲剂0.02％～0.2％；引发剂0.3％～1.2％；消泡剂0.05％～0.2％；pH调节剂0.1％～0.5％；防腐杀菌剂0.05％～0.2％；水45％～55％；另外,本发明还公开了该防水涂料的制备方法。本发明公开的防水涂料耐水白性能好,环保无毒,在保证低温成膜性能的同时提高防水膜的强度。(A waterproof coating comprises the following components in percentage by weight: waterproof coating: 75 to 85 percent of special high polymer emulsion; 0.5 to 1.5 percent of water repellent; 0.1 to 0.5 percent of defoaming agent; 0.1 to 0.5 percent of thickening agent; 0.5-1.0% of a coupling agent; 0.1 to 0.5 percent of bactericide; 15 to 25 percent of water; wherein, the special high polymer emulsion comprises: 15 to 25 percent of butyl acrylate; 8 to 20 percent of methyl methacrylate; 8 to 20 percent of styrene; 0.2 to 1.0 percent of methacrylic acid; 0.1 to 0.5 percent of acrylamide; 0.5 to 2 percent of organic silicon monomer; 0.5 to 2 percent of composite emulsifier; 0.02 to 0.2 percent of buffering agent; 0.3 to 1.2 percent of initiator; 0.05 to 0.2 percent of defoaming agent; 0.1 to 0.5 percent of pH regulator; 0.05 to 0.2 percent of antiseptic bactericide; 45 to 55 percent of water; in addition, the invention also discloses a preparation method of the waterproof coating. The waterproof coating disclosed by the invention has good water-whitening resistance, is environment-friendly and nontoxic, and improves the strength of a waterproof film while ensuring the low-temperature film-forming property.)

1. A preparation method of a waterproof coating is characterized by comprising the following steps:

(1) preparing a seed emulsion:

firstly, mixing a proper amount of water, a composite emulsifier, styrene, butyl acrylate, methacrylic acid and acrylamide, and dispersing at a high speed for 25-30min to prepare a pre-emulsion A;

secondly, taking a proper amount of water, a buffering agent and less than 1/3 of the pre-emulsion A into a reactor, keeping stirring at a constant speed, slowly heating to 70-75 ℃, continuing to react for 10-15min when a blue phase appears, slowly dripping the rest of the pre-emulsion A, replenishing an initiator solution in batches, reacting at a constant temperature for 25-30min, heating to 75-85 ℃, reacting for 45-60min again, and cooling to room temperature to prepare the seed emulsion;

(2) preparing a special high polymer emulsion:

mixing the residual composite emulsifier, water, methyl methacrylate, residual butyl acrylate, residual methacrylic acid, acrylamide and an organic silicon monomer at a high speed, and dispersing to prepare a pre-emulsion B;

dropping the seed emulsion into a kettle gradually, slowly heating to 70-75 ℃, adding an initiator solution in batches, reacting for 25-30min at a constant temperature, heating to 75-85 ℃, reacting for 45-60min, cooling to below 45 ℃, adding a pH regulator, a defoaming agent and an antiseptic bactericide, stirring uniformly, and filtering to obtain the special high polymer emulsion;

(3) preparing a waterproof coating:

and (3) uniformly dispersing and filtering the special high polymer emulsion, the thickening agent, the bactericide, the water repellent, water and the coupling agent to prepare the waterproof coating.

2. The method of claim 1, wherein the viscosity of the pre-emulsion A and the viscosity of the pre-emulsion B are both 600-800 mPas.

3. A waterproof paint produced by the production method according to claim 1, characterized in that: comprises the following components in percentage by weight:

waterproof coating:

wherein, the special high polymer emulsion comprises:

4. the waterproof paint according to claim 3, characterized in that: the organic silicon monomer is one or a mixture of two of vinyl trimethoxy silane and gamma-methacryloxypropyl triethoxy silane.

5. The waterproof paint according to claim 4, characterized in that: the weight percentage of the organosilicon monomer is 0.8% -1.5%.

6. The waterproof paint according to claim 3, characterized in that: the butyl acrylate accounts for 18.4 to 20.8 percent by weight.

7. The waterproof paint according to claim 3, characterized in that: the composite emulsifier comprises one or more of sodium vinylsulfonate, sodium acrylamido isopropyl sulfonate and 2-allyl ether 3-hydroxy propane-1-sodium sulfonate; the antiseptic bactericide is isothiazolinone compound.

8. The waterproof paint according to claim 3, characterized in that: the buffer comprises one or more of sodium bicarbonate, sodium acetate and sodium citrate; the initiator is one of ammonium persulfate and potassium persulfate.

9. The waterproof paint according to claim 3, characterized in that: the defoaming agent is mineral oil, and the bactericide is an efficient environment-friendly mildew-proof and bacteria-proof bactericide.

10. The waterproof paint according to claim 3, characterized in that: the thickening agent is one of nonionic polyurethane associative thickening agents; the water repellent is organic silicon; the coupling agent is one of silane coupling agents KH-550 and KH-570.

Technical Field

The scheme belongs to the field of chemical materials, and particularly relates to the field of application of architectural chemical materials.

Background

The outer wall water resistance is an important component in the building engineering, the leakage problem is a common quality problem of the building, the leakage not only disturbs the normal life of people, but also directly influences the service life of the whole building, and polymer compound coatings are commonly used on the market and coated on the surface of the outer wall to serve as a waterproof layer, so that the water resistance of the building is improved.

However, in the long-term practice, it has been found that the prior art waterproof coatings present two problems: firstly, the water and white resistance is poor, mainly because the raw materials of the waterproof coating contain more hydrophilic materials such as surfactants and the like, the hydrophilic materials are provided with molecules with polar groups, have high affinity to water and can attract water molecules, the water can be spread on the surface of the hydrophilic materials and can be automatically absorbed into the materials through the capillary action, so that the materials are whitened, the internal structure of the materials is damaged, and various performances of the waterproof materials are influenced, obviously, the waterproof coating is very unfavorable for the waterproof materials; then, the existing waterproof coating uses harmful substances such as plasticizer, etc., because the waterproof coating is generally rigid high polymer to ensure that the waterproof coating has enough strength, and the low-temperature film forming property needs to be realized by the plasticizer, the conventional high polymer emulsion is difficult to balance the cohesive strength and the low-temperature film forming property, and as a material used in a large scale and a large range, the waterproof coating contains the harmful substances such as plasticizer, etc., which can cause adverse effects on human body, environment, etc.

Disclosure of Invention

Based on the problems in the prior art, the invention provides the waterproof coating and the preparation method thereof, the waterproof coating has good water-whitening resistance, is environment-friendly and nontoxic, and can ensure the low-temperature film-forming property and improve the strength of the waterproof film.

A preparation method of a waterproof coating comprises the following steps:

(1) preparing a seed emulsion:

firstly, mixing a proper amount of water, a composite emulsifier, styrene, butyl acrylate, methacrylic acid and acrylamide, and dispersing at a high speed for 25-30min to prepare a pre-emulsion A;

secondly, taking a proper amount of water, a buffering agent and less than 1/3 of the pre-emulsion A into a reactor, keeping stirring at a constant speed, slowly heating to 70-75 ℃, continuing to react for 10-15min when a blue phase appears, slowly dripping the rest of the pre-emulsion A, replenishing an initiator solution in batches, reacting at a constant temperature for 25-30min, heating to 75-85 ℃, reacting for 45-60min again, and cooling to room temperature to prepare the seed emulsion;

(2) preparing a special high polymer emulsion:

mixing the residual composite emulsifier, water, methyl methacrylate, residual butyl acrylate, residual methacrylic acid, acrylamide and an organic silicon monomer at a high speed, and dispersing to prepare a pre-emulsion B;

dropping the seed emulsion into a kettle gradually, slowly heating to 70-75 ℃, adding an initiator solution in batches, reacting at a constant temperature for 25-30min, heating to 75-85 ℃, reacting for 45-60min, cooling to below 45 ℃, adding a pH regulator, a defoaming agent and an antiseptic bactericide, stirring uniformly, and filtering to obtain the special high polymer emulsion;

(3) preparing a waterproof coating:

and (3) uniformly dispersing and filtering the special high polymer emulsion, the thickening agent, the bactericide, the water repellent, water and the coupling agent to prepare the waterproof coating.

Further, the viscosity of the pre-emulsion a and the viscosity of the pre-emulsion B are both 600-800mPa · s.

The waterproof coating prepared by the preparation method comprises the following components in percentage by weight:

waterproof coating:

wherein, the special high polymer emulsion comprises:

further, the organosilicon monomer is one or a mixture of two of vinyl trimethoxy silane and gamma-methacryloxypropyl triethoxy silane.

Specifically, the organosilicon monomer accounts for 0.8-1.5 wt%.

Further, the butyl acrylate accounts for 18.4-20.8% by weight.

Further, the compound emulsifier comprises one or a combination of several of sodium vinylsulfonate, sodium acrylamidoisopropyl sulfonate and sodium 2-allyl ether 3-hydroxypropane-1-sulfonate; the antiseptic bactericide is isothiazolinone compounds;

the buffer comprises one or more of sodium bicarbonate, sodium acetate and sodium citrate; the initiator is one of ammonium persulfate and potassium persulfate.

The defoaming agent is mineral oil, and the bactericide is an efficient environment-friendly mildew-proof and bacteria-proof bactericide.

The thickening agent is one of nonionic polyurethane associative thickening agents; the water repellent is organic silicon; the coupling agent is one of silane coupling agents KH-550 and KH-570.

Compared with the prior art, the scheme of the invention has the advantages that:

(1) the reactive composite emulsifier is adopted, free surface active substances are not used, the addition of hydrophilic substances is reduced, and the water-whitening resistance of the waterproof coating is improved;

(2) the core-shell polymerization technology is used in the waterproof coating, the core part is polymerized firstly through a step-by-step polymerization mode and the difference of hydrophobicity of monomers, and then the shell part is polymerized, coated and grafted on the core polymer, so that a molecular structure with soft outside and hard inside is realized, the molecular structure with soft outside and hard inside can not only enhance the wetting effect on a base layer, improve the bonding strength, but also improve the cohesive strength of the waterproof coating;

(3) the waterproof coating has good film-forming property due to the external soft structure, and harmful substances such as plasticizer and the like do not need to be added, so that the working procedures are reduced, the cost is reduced, and the safety and environmental protection performance of the waterproof coating are greatly improved;

(4) meanwhile, a self-crosslinking monomer is introduced on the premise of not damaging the original surface structure, the amide group of acrylamide reacts with carboxyl and hydroxyl in the polymerization process to form a local crosslinking structure, and the reactions occur in the polymer molecules; under the condition of ensuring good low-temperature film-forming property, the surface strength of the waterproof coating is improved, wherein the solid content of the special high polymer emulsion is 45-50%, and the lowest film-forming temperature is 0-5 ℃.

Detailed Description

A waterproof coating comprises the following components in percentage by weight:

waterproof coating:

wherein, the special high polymer emulsion comprises:

the water repellent and the special waterproof agent for exterior wall water proofing have the advantages of acid and alkali resistance, aging resistance, carbonization resistance, saltpetering resistance, moisture resistance, mildew resistance and the like, and are mainly used for water proofing (spraying) of ceramic tile exterior walls, water proofing of ceramic tile seams of toilets, kitchens, balconies and the like, water proofing of concrete wall surfaces, ceramic tiles, stones, woods, cement surfaces and road surfaces, and especially application of ancient architecture renovation (temple, church and national ancient cultural relics of conservation).

Methyl methacrylate is an organic compound, also called MMA, methyl methacrylate for short, is an important chemical raw material, and is a monomer for producing transparent plastic polymethyl methacrylate (organic glass, PMMA). Flammable, strong pungent odor, moderate toxicity, and should be avoided for long-term contact.

Methacrylic acid is colorless crystals or a transparent liquid, and has an pungent odor. Can be dissolved in hot water, ethanol, diethyl ether, etc. Easy to polymerize into water-soluble polymer. It is combustible, has danger of combustion when meeting high heat and open fire, and can produce toxic gas when heated and decomposed.

Acrylamide (CAS No. 79-06-1) is colorless transparent flaky crystal, odorless and toxic. The relative density is 1.122, and the melting point is 84-85 ℃. Dissolving in water and ethanol, and slightly dissolving in benzene and toluene. Easy sublimation and easy polymerization. The solid is stable at room temperature and polymerizes violently when molten. Prepared by hydrolyzing acrylonitrile with sulfuric acid or with a metal catalyst.