阅读说明：本技术 一种可用于制备聚合物水泥基防水涂料的硅-丙乳液制备方法 (Preparation method of silicon-acrylic emulsion for preparing polymer cement-based waterproof coating ) 是由 李晴龙 耿进玉 李�东 于 2020-12-29 设计创作，主要内容包括：本发明公开了一种可用于制备聚合物水泥基防水涂料的硅-丙乳液制备方法。采用乳液聚合法,以乙烯基单体、含乙烯基功能性有机硅单体等为共聚单体,借助可聚合乳化剂和机械搅拌,滴加引发剂使单体先在水中聚合成核,继续滴加引发剂及剩余单体进行双键的自由基聚合,最后冰水浴淬灭反应,并调节pH值即得具有核壳结构的硅-丙乳液。本发明制得的硅-丙乳液制备聚合物水泥基防水涂料,不仅可显著提高防水涂层的耐水性及力学性能,另外由于分子结构上的硅氧键向外层整齐排列,使涂层具有优异的疏水性及透气透湿性,改善在潮湿基面施工的起鼓脱落问题。(The invention discloses a preparation method of a silicon-acrylic emulsion for preparing a polymer cement-based waterproof coating. Adopting an emulsion polymerization method, taking vinyl monomers, vinyl-containing functional organic silicon monomers and the like as comonomers, adding a polymerizable emulsifier and mechanically stirring, dropwise adding an initiator to ensure that the monomers are polymerized into nuclei in water, continuously dropwise adding the initiator and the rest monomers to carry out double-bond free radical polymerization, finally carrying out quenching reaction in an ice-water bath, and adjusting the pH value to obtain the silicon-acrylic emulsion with the core-shell structure. The polymer cement-based waterproof coating prepared from the silicon-acrylic emulsion prepared by the invention not only can obviously improve the water resistance and mechanical property of a waterproof coating, but also has excellent hydrophobicity, air permeability and moisture permeability due to the regular arrangement of silicon-oxygen bonds on a molecular structure towards an outer layer, and the problem of swelling and falling during construction on a damp base surface is solved.)

1. A preparation method of silicone-acrylic emulsion for preparing polymer cement-based waterproof paint is characterized by comprising the following steps:

1) according to the mass portion, firstly, 0.2-0.3 portion of allyloxy nonyl phenol polyoxyethylene ether, 0.5-0.7 portion of anionic/nonionic polymerizable emulsifier consisting of allyloxy nonyl phenol polyoxyethylene ether ammonium sulfate and 52-56 portions of water are added into a reactor and uniformly stirred, 10-12 portions of methacrylic acid and 3-5 portions of ethyl methacrylate are slowly added, the temperature is raised while stirring, and the mixture reacts for 30min at 50 ℃ to obtain stable milky pre-emulsion;

2) regulating the pH value to 7.5 +/-0.1 by using a pH regulator, heating to 80 ℃, then dropwise adding 5-7 parts of water-soluble initiator aqueous solution, reacting for a certain time for nucleation to obtain blue seed emulsion;

3) respectively and simultaneously slowly dripping 20-24 parts of methacrylic acid, 6-10 parts of ethyl methacrylate and 8-12 parts of hydroxypropyl acrylate to form a mixed monomer, 0.4-0.6 part of allyloxy nonylphenol polyoxyethylene ether, 1.0-1.5 parts of anionic/nonionic polymerizable emulsifier consisting of allyloxy nonylphenol polyoxyethylene ether ammonium sulfate, 10-18 parts of water-soluble initiator aqueous solution and 6-12 parts of vinyl siloxane, continuously reacting for about 3-5 h after dripping for 2-3 h, regulating the pH value to 7.5 +/-0.1 by using a pH regulator after quenching reaction in an ice water bath, and filtering to obtain the slightly blue silicon-acrylic emulsion for preparing the polymer cement waterproof coating.

The liquid material for preparing the polymer cement-based waterproof coating from the prepared silicone-acrylic emulsion comprises the following components in parts by mass: 95-98 parts of silicone-acrylate emulsion, 0.2-0.4 part of dispersing agent, 0.1-0.3 part of defoaming agent, 0.1-0.2 part of preservative and 0-5 parts of water; the powder comprises the following components in parts by mass: 30-50 parts of 42.5 Portland cement, 20-40 parts of 325-mesh coarse whiting, 30-40 parts of quartz powder, 10-20 parts of sericite powder, 0.1-0.3 part of defoaming agent and 0.1-0.3 part of water-retaining agent.

The liquid material component and the powder material component are mixed and stirred uniformly according to the mass ratio of 1:1.2 for use.

2. The method for preparing the silicone-acrylic emulsion used for preparing the polymer cement-based waterproof coating according to claim 1, wherein an emulsifying system used for preparing the silicone-acrylic emulsion is an anionic-nonionic polymerizable emulsifier, and the polymerizable emulsifier has a molecular structure containing hydrophilic and lipophilic emulsifying groups and double bonds participating in polymerization, so that molecules of the polymerizable emulsifier can be bonded to a polymer main chain, and the small-molecule emulsifier is prevented from migrating to the surface to influence water resistance, storage stability and the like.

3. The method for preparing the silicone-acrylic emulsion used for preparing the polymer cement-based waterproof coating material according to claim 1, wherein the anionic-nonionic polymerizable emulsifier is allyloxynonylphenol polyoxyethylene ether ammonium sulfate-allyloxynonylphenol polyoxyethylene ether.

4. The method for preparing the silicone-acrylic emulsion used for preparing the polymer cement-based waterproof coating according to claim 1, wherein the vinyl monomer is a mixture of two or more of methacrylic acid, ethyl methacrylate and hydroxypropyl acrylate in any proportion.

5. The preparation method of the silicone-acrylic emulsion for preparing the polymer cement-based waterproof coating according to claim 1, wherein the organosilicon monomer is a mixture of two or more of vinyl triisopropoxysilane and gamma-methylpropenylacyloxy propyl trimethoxysilane in any proportion.

6. The preparation method of the silicone-acrylic emulsion for preparing the polymer cement-based waterproof coating material according to claim 1, wherein the pH regulator is Dow AMP-95.

7. The preparation method of the silicone-acrylic emulsion for preparing the polymer cement-based waterproof coating material, which is characterized in that the termination reaction is continued by ice-water bath quenching according to the method 1.

Technical Field

The invention belongs to the technical field of building materials, and particularly relates to a preparation method of a silicon-acrylic emulsion for preparing a polymer cement-based waterproof coating.

Technical Field

Along with the development of the draft of general building and municipal engineering waterproof standard, clear regulations are provided for the working life of engineering waterproof design, which provides more strict requirements for the water resistance of waterproof materials, the comprehensive properties such as the water resistance of polymer cement waterproof coatings prepared by acrylic emulsion commonly adopted in the market at present are difficult to meet the requirements, and the development of emulsion which can be used for preparing more excellent comprehensive properties such as the water resistance is necessary in order to meet the continuous improvement of the building waterproof requirements of people.

Disclosure of Invention

The invention aims to solve the common problems recorded in the technical background part and provides a preparation method of a silicon-acrylic emulsion for preparing a polymer cement-based waterproof coating. The method has wide monomer composition range and wide adjustable range through molecular design, and the polymer cement waterproof coating prepared from the obtained silicon-acrylic emulsion not only can obviously improve the water resistance and mechanical property of a waterproof coating, but also has excellent hydrophobicity, air permeability and moisture permeability because silicon-oxygen bonds on a molecular structure are regularly arranged towards an outer layer, so that the problem of bulging and falling off during construction on a damp base surface is solved.

In order to achieve the purpose, the invention adopts the technical scheme that:

1) according to the mass portion, firstly, 0.2-0.3 portion of allyloxy nonyl phenol polyoxyethylene ether, 0.5-0.7 portion of anionic/nonionic polymerizable emulsifier consisting of allyloxy nonyl phenol polyoxyethylene ether ammonium sulfate and 52-56 portions of water are added into a reactor and uniformly stirred, 10-12 portions of methacrylic acid and 3-5 portions of ethyl methacrylate are slowly added, the temperature is raised while stirring, and the mixture reacts for 30min at 50 ℃ to obtain stable milky pre-emulsion;

2) regulating the pH value to 7.5 +/-0.1 by using a pH regulator, heating to 80 ℃, then dropwise adding 5-7 parts of water-soluble initiator aqueous solution, reacting for a certain time for nucleation to obtain blue seed emulsion;

3) respectively and simultaneously slowly dripping 20-24 parts of methacrylic acid, 6-10 parts of ethyl methacrylate and 8-12 parts of hydroxypropyl acrylate to form a mixed monomer, 0.4-0.6 part of allyloxy nonylphenol polyoxyethylene ether, 1.0-1.5 parts of anionic/nonionic polymerizable emulsifier consisting of allyloxy nonylphenol polyoxyethylene ether ammonium sulfate, 10-18 parts of water-soluble initiator aqueous solution and 6-12 parts of vinyl siloxane, continuously reacting for about 3-5 h after dripping for 2-3 h, regulating the pH value to 7.5 +/-0.1 by using a pH regulator after quenching reaction in an ice water bath, and filtering to obtain the slightly blue silicon-acrylic emulsion for preparing the polymer cement waterproof coating.

The liquid material for preparing the polymer cement-based waterproof coating from the prepared silicone-acrylic emulsion comprises the following components in parts by mass: 95-98 parts of silicone-acrylate emulsion, 0.2-0.4 part of dispersing agent, 0.1-0.3 part of defoaming agent, 0.1-0.2 part of preservative and 0-5 parts of water; the powder comprises the following components in parts by mass: 30-50 parts of 42.5 Portland cement, 20-40 parts of 325-mesh coarse whiting, 30-40 parts of quartz powder, 10-20 parts of sericite powder, 0.1-0.3 part of defoaming agent and 0.1-0.3 part of water-retaining agent.

The liquid material component and the powder material component are mixed and stirred uniformly according to the mass ratio of 1:1.2 for use.

The emulsifying system selected for preparing the silicon-acrylic emulsion is an anionic-nonionic polymerizable emulsifier, and the molecular structure of the polymerizable emulsifier contains hydrophilic and lipophilic emulsifying groups and double bonds participating in polymerization, so that the polymerizable emulsifier molecules can be bonded to a polymer main chain, and the small molecular emulsifier is prevented from migrating to the surface to influence water resistance, storage stability and the like.

The anionic-nonionic polymerizable emulsifier is allyloxy nonylphenol polyoxyethylene ether ammonium sulfate-allyloxy nonylphenol polyoxyethylene ether.

The vinyl monomer is a mixture of two or more of methacrylic acid, ethyl methacrylate and hydroxypropyl acrylate in any proportion.

The organosilicon monomer is a mixture of two or more than two of vinyl triisopropoxysilane and gamma-methylpropene acyloxy propyl trimethoxy silane in any proportion.

The pH regulator is Dow AMP-95.

The termination reaction was continued by ice-water bath quenching.

The silicone-acrylate emulsion prepared by the invention selects a polymerizable emulsifier, the molecular structure of which contains hydrophilic and oleophilic emulsifying groups and double bonds participating in polymerization, so that the molecules of the emulsifier can be bonded to the main chain of a polymer, and the micromolecule emulsifier is prevented from migrating to the surface, thereby improving the water resistance, the storage stability and the like of the emulsion.

Detailed Description

The following examples are provided to illustrate the present invention to facilitate the reproduction of experimental results by those skilled in the art with reference to the description, but are not intended to limit the scope of the present invention.

Example 1:

firstly, adding an anionic/nonionic polymerizable emulsifier consisting of 0.2 part of allyloxy nonylphenol polyoxyethylene ether, 0.7 part of allyloxy nonylphenol polyoxyethylene ether ammonium sulfate and 56 parts of water into a reactor, uniformly stirring, slowly adding 10 parts of methacrylic acid and 5 parts of ethyl methacrylate, heating while stirring, and reacting at 50 ℃ for 30min to obtain a stable milky pre-emulsion; regulating the pH value to 7.5 +/-0.1 by using a pH regulator, heating to 80 ℃, then dripping 1/3 aqueous solution of an initiator consisting of 0.5 part of ammonium persulfate and 16 parts of water, mixing the aqueous solution of the water-soluble initiator with the aqueous solution of the initiator, reacting for a certain time to nucleate to obtain blue seed emulsion; respectively and simultaneously slowly dripping 23 parts of methacrylic acid, 6 parts of ethyl methacrylate and 11 parts of hydroxypropyl acrylate to form a mixed monomer, 0.5 part of allyloxy nonylphenol polyoxyethylene ether, 1.3 parts of anionic/nonionic polymerizable emulsifier consisting of allyloxy nonylphenol polyoxyethylene ether ammonium sulfate, the rest 2/3 initiator aqueous solution and 6 parts of vinyl triisopropoxysilane, continuously reacting for about 3h to 5h after dripping for 2h to 3h, adjusting the pH value to 7.5 +/-0.1 by using a pH regulator after quenching reaction in ice water bath, and filtering to obtain the slightly blue-light silicon-propylene emulsion which can be used for preparing the polymer cement waterproof coating.

The liquid material for preparing the polymer cement-based waterproof coating from the prepared silicone-acrylic emulsion comprises the following components in parts by mass: 95 parts of silicone-acrylic emulsion, 0.2 part of BYK23160, 0.1 part of ST2438 and 0.1 part of preservative D7; the powder comprises the following components in parts by mass: 30 parts of 42.5 Portland cement, 30 parts of 325-mesh coarse whiting, 30 parts of quartz powder, 10 parts of sericite powder, 0.2 part of P803 and 0.2 part of 2 ten thousand viscosity cellulose.

The liquid material component and the powder material component are mixed and stirred uniformly according to the mass ratio of 1:1.2 for use.

Example 2:

firstly, adding an anionic/nonionic polymerizable emulsifier consisting of 0.3 part of allyloxy nonylphenol polyoxyethylene ether, 0.6 part of allyloxy nonylphenol polyoxyethylene ether ammonium sulfate and 56 parts of water into a reactor, uniformly stirring, slowly adding 9 parts of methacrylic acid and 3 parts of ethyl methacrylate, heating while stirring, and reacting at 50 ℃ for 30min to obtain a stable milky pre-emulsion; regulating the pH value to 7.5 +/-0.1 by using a pH regulator, heating to 80 ℃, then dripping 1/3 aqueous solution of an initiator consisting of 0.5 part of ammonium persulfate and 16 parts of water, mixing the aqueous solution of the water-soluble initiator with the aqueous solution of the initiator, reacting for a certain time to nucleate to obtain blue seed emulsion; respectively and simultaneously slowly dripping 24 parts of methacrylic acid, 10 parts of ethyl methacrylate and 8 parts of hydroxypropyl acrylate to form a mixed monomer, 0.6 part of allyloxy nonylphenol polyoxyethylene ether and 1 part of allyloxy nonylphenol polyoxyethylene ether ammonium sulfate to form an anionic/nonionic polymerizable emulsifier, the rest 2/3 initiator aqueous solution and 7 parts of gamma-methyl propylene acyloxy propyl trimethoxy silane for continuously reacting for about 3 to 5 hours after finishing dripping for 2 to 3 hours, regulating the pH value to 7.5 +/-0.1 by using a pH regulator after quenching reaction in ice water bath, and filtering to obtain the silicon-acrylic emulsion with slight blue light for preparing the polymer cement waterproof coating.

The liquid material for preparing the polymer cement-based waterproof coating from the prepared silicone-acrylic emulsion comprises the following components in parts by mass: 96 parts of silicone-acrylic emulsion, 0.2 part of BYK23160, 0.3 part of ST2438, 0.1 part of preservative D7 and 3 parts of water; the powder comprises the following components in parts by mass: 40 parts of 42.5 Portland cement, 20 parts of 325-mesh coarse whiting, 30 parts of quartz powder, 10 parts of sericite powder, 0.2 part of P803 and 0.1 part of 2 ten thousand viscosity cellulose.

The liquid material component and the powder material component are mixed and stirred uniformly according to the mass ratio of 1:1.2 for use.

Example 3:

firstly, adding an anionic/nonionic polymerizable emulsifier consisting of 0.3 part of allyloxy nonylphenol polyoxyethylene ether, 0.5 part of allyloxy nonylphenol polyoxyethylene ether ammonium sulfate and 54 parts of water into a reactor, uniformly stirring, slowly adding 11 parts of methacrylic acid and 4 parts of ethyl methacrylate, heating while stirring, and reacting at 50 ℃ for 30min to obtain a stable milky pre-emulsion; regulating the pH value to 7.5 +/-0.1 by using a pH regulator, heating to 80 ℃, then dripping 1/3 aqueous solution of an initiator consisting of 0.5 part of ammonium persulfate and 16 parts of water, mixing the aqueous solution of the water-soluble initiator with the aqueous solution of the initiator, reacting for a certain time to nucleate to obtain blue seed emulsion; respectively and simultaneously slowly dripping 22 parts of methacrylic acid, 7 parts of ethyl methacrylate and 12 parts of hydroxypropyl acrylate to form a mixed monomer, 0.4 part of allyloxy nonylphenol polyoxyethylene ether, 1.4 parts of anionic/nonionic polymerizable emulsifier consisting of allyloxy nonylphenol polyoxyethylene ether ammonium sulfate, the rest 2/3 initiator aqueous solution and 5 parts of vinyl triisopropoxysilane, continuously reacting for about 3h to 5h after dripping for 2h to 3h, adjusting the pH value to 7.5 +/-0.1 by using a pH regulator after quenching reaction in ice water bath, and filtering to obtain the slightly blue-light silicon-propylene emulsion which can be used for preparing the polymer cement waterproof coating.

The liquid material for preparing the polymer cement-based waterproof coating from the prepared silicone-acrylic emulsion comprises the following components in parts by mass: 97 parts of silicone-acrylic emulsion, 0.3 part of BYK23160, 0.2 part of ST2438, 0.2 part of preservative D7 and 4 parts of water; the powder comprises the following components in parts by mass: 50 parts of 42.5 Portland cement, 20 parts of 325-mesh coarse whiting, 30 parts of quartz powder, 20 parts of sericite powder, 0.2 part of P803 and 0.1 part of 2 ten thousand viscosity cellulose.

The liquid material component and the powder material component are mixed and stirred uniformly according to the mass ratio of 1:1.2 for use.

Example 4:

firstly, adding an anionic/nonionic polymerizable emulsifier consisting of 0.2 part of allyloxy nonylphenol polyoxyethylene ether, 0.6 part of allyloxy nonylphenol polyoxyethylene ether ammonium sulfate and 52 parts of water into a reactor, uniformly stirring, slowly adding 12 parts of methacrylic acid and 3 parts of ethyl methacrylate, heating while stirring, and reacting at 50 ℃ for 30min to obtain a stable milky pre-emulsion; regulating the pH value to 7.5 +/-0.1 by using a pH regulator, heating to 80 ℃, then dripping 1/3 aqueous solution of an initiator consisting of 0.5 part of ammonium persulfate and 16 parts of water, mixing the aqueous solution of the water-soluble initiator with the aqueous solution of the initiator, reacting for a certain time to nucleate to obtain blue seed emulsion; respectively and simultaneously slowly dripping 21 parts of methacrylic acid, 8 parts of ethyl methacrylate and 9 parts of hydroxypropyl acrylate to form a mixed monomer, 0.5 part of allyloxy nonylphenol polyoxyethylene ether and 1.2 parts of allyloxy nonylphenol polyoxyethylene ether ammonium sulfate to form an anionic/nonionic polymerizable emulsifier, remaining 2/3 initiator aqueous solution and 8 parts of gamma-methyl propylene acyloxy propyl trimethoxy silane, controlling the reaction to continue reacting for about 3 to 5 hours after dripping for 2 to 3 hours, regulating the pH value to 7.5 +/-0.1 by using a pH regulator after quenching reaction in an ice water bath, and filtering to obtain the slightly blue silicon-propylene emulsion which can be used for preparing the polymer cement waterproof coating.

The liquid material for preparing the polymer cement-based waterproof coating from the prepared silicone-acrylic emulsion comprises the following components in parts by mass: 98 parts of silicone-acrylic emulsion, 0.4 part of BYK23160, 0.2 part of ST2438, 0.2 part of preservative D7 and 5 parts of water; the powder comprises the following components in parts by mass: 40 parts of 42.5 Portland cement, 40 parts of 325-mesh coarse whiting, 40 parts of quartz powder, 20 parts of sericite powder, 0.3 part of P803 and 0.1 part of 2 ten thousand viscosity cellulose.

The liquid material component and the powder material component are mixed and stirred uniformly according to the mass ratio of 1:1.2 for use.

Comparative example 1: a silicone-acrylic emulsion useful for preparing a polymer cement-based waterproof coating is prepared by using an anionic emulsifier as a whole, and the other steps are the same as in example 1. Under the condition, the prepared emulsion has poor storage stability, and the emulsion breaking phenomenon can occur after the powder is added and stirred.

Comparative example 2: a silicone-acrylic emulsion useful for preparing a polymer cement-based waterproofing paint was prepared by replacing the silicone-acrylic emulsion obtained in example 1 with an equivalent amount of R161N emulsion, otherwise the same as in example 1. Under the condition, the performance of the polymer cement waterproof coating is qualified by reference to GB/T23445-2009, but the water absorption is higher.

Comparative example 3: an emulsion prepared by removing functional vinyl silane monomer in silicone-acrylic emulsion used for preparing polymer cement-based waterproof paint is prepared as in example 1. Under the condition, the polymer cement waterproof coating has smaller performance reference GB/T23445-2009 tensile strength and larger water absorption.

The tensile property, the adhesive strength, the water absorption rate and the like of the examples and the comparative examples are detected by referring to GB/T23445-:

table 1: the result of the detection

From the above-mentioned examples and comparative example test results, it can be seen that the silicone-acrylic emulsion prepared by the present invention, by selecting a polymerizable anionic/non-emulsifier system, the molecular structure of which contains hydrophilic and lipophilic emulsifying groups and double bonds participating in polymerization, can ensure that the emulsifier molecules are bonded to the polymer main chain, and prevent the small molecule emulsifier from migrating to the surface, thereby improving the water resistance and storage stability of the emulsion, etc., and the siloxane molecular structure introduced in the molecular structure is helical, the methyl groups surrounding the Si-O bonds are arranged and rotated outwards, and the molecular volume is large, the cohesive energy is low, so that the prepared polymer cement waterproof coating has good waterproof and air permeability, does not swell and fall off when immersed in water for a long time, and the bonding strength of the wet base surface is high.