阅读说明：本技术 一种石墨烯外墙板自清洁涂料及其制备方法 (Graphene external wall panel self-cleaning coating and preparation method thereof ) 是由 冯江涛 张普敦 王力 刘牧 于 2020-08-19 设计创作，主要内容包括：本发明公开了一种石墨烯外墙板自清洁涂料,包括以下重量的各组分：碱性硅溶胶20-60份,苯乙烯丙烯酸酯乳液10-30份,石墨烯2-8份,纳米氧化钇1-5份,纳米氧化铈1-5份,成膜助剂0.1-1份,表面活性剂0.5-3份,增稠剂5-10份,分散剂0.1-1份,消泡剂0.1-1份,颜料10-20份,去离子水10-30份。本发明还公开了一种石墨烯外墙板自清洁涂料的制备方法。本发明采用上述石墨烯外墙板自清洁涂料及其制备方法,能够解决现有的自清洁涂料与外墙结合力低、自清洁能力差的问题。(The invention discloses a graphene external wall panel self-cleaning coating which comprises the following components in parts by weight: 20-60 parts of alkaline silica sol, 10-30 parts of styrene acrylate emulsion, 2-8 parts of graphene, 1-5 parts of nano yttrium oxide, 1-5 parts of nano cerium oxide, 0.1-1 part of film-forming additive, 0.5-3 parts of surfactant, 5-10 parts of thickener, 0.1-1 part of dispersant, 0.1-1 part of defoamer, 10-20 parts of pigment and 10-30 parts of deionized water. The invention also discloses a preparation method of the graphene external wall panel self-cleaning coating. By adopting the graphene external wall panel self-cleaning coating and the preparation method thereof, the problems of low binding force and poor self-cleaning capability of the existing self-cleaning coating and an external wall can be solved.)

1. The utility model provides a graphite alkene side fascia automatically cleaning coating which characterized in that: comprises the following components by weight:

2. the graphene external wall panel self-cleaning coating as claimed in claim 1, wherein: the particle size of nano silicon dioxide ions in the alkaline silica sol is not more than 600nm, the content of silicon dioxide is 20-30%, and the proportion of silicon dioxide and sodium oxide is not less than 40%.

3. The graphene external wall panel self-cleaning coating as claimed in claim 1, wherein: the film-forming assistant is one or a mixture of more of zinc oxide, butyl silicate, butyl acetate or sodium methyl silicate.

4. The graphene external wall panel self-cleaning coating as claimed in claim 1, wherein: the surfactant is sodium benzene sulfonate.

5. The graphene external wall panel self-cleaning coating as claimed in claim 1, wherein: the thickening agent is hydroxyethyl cellulose, CMC or the mixture of the hydroxyethyl cellulose and the CMC; the dispersant is sodium hexametaphosphate; the defoaming agent is tributyl phosphate.

6. The preparation method of the graphene external wall panel self-cleaning coating according to any one of claims 1 to 5, characterized by comprising the following steps:

s1, adding nano yttrium oxide and nano cerium oxide into a certain amount of deionized water, and performing ultrasonic uniform dispersion for 40-60 minutes at the rotating speed of 1000-2000rpm to prepare yttrium-cerium composite ceramic nano liquid;

s2, adding graphene into a certain amount of deionized water, adding a certain amount of ethanol solution into the deionized water, performing ultrasonic uniform dispersion for 90-180 minutes at the rotating speed of 1000-2000rpm, and evaporating ethanol to prepare graphene dispersion liquid;

s3, adding a film forming agent into a reaction kettle, adding a certain amount of deionized water, stirring, then sequentially adding a surfactant, a thickening agent, a dispersing agent and a defoaming agent, stirring uniformly, then slowly adding alkaline silica sol into the reaction kettle, adding a styrene acrylate emulsion, a graphene dispersion liquid and a yttrium cerium composite ceramic nano liquid, stirring uniformly, and grinding and dispersing by a grinder for 1-2 hours;

s4, adding the pigment and all the deionized water into the grinding material, and stirring and mixing uniformly at the rotating speed of 800-1200rpm to obtain the coating.

Technical Field

The invention belongs to the technical field of self-cleaning coatings for buildings, and particularly relates to a graphene external wall panel self-cleaning coating and a preparation method thereof.

Background

Along with the continuous aggravation of environmental pollution, haze in the air is more and more serious, and oily smog, automobile exhaust, industrial waste gas and the like contained in the air bring serious erosion and pollution to the outer wall of a building, so that the attractiveness and the performance of the outer wall of the building are influenced. The contact angle of the self-cleaning coating with water is large, and the wettability of the self-cleaning coating with water is poor, so that water slides off the coating under the action of gravity and is difficult to stay on the coating. Sundries can be washed off from the coating under the action of water, the surface of the coating is kept clean, maintenance cost can be reduced, labor force requirements can be reduced, and meanwhile the use of cleaning agents can be reduced. Therefore, the self-cleaning coating is widely applied to the outer wall of the building. The existing self-cleaning coating has the problems of low binding force with an outer wall and poor self-cleaning capability.

Disclosure of Invention

The invention aims to provide a graphene external wall panel self-cleaning coating, and solves the problems of low binding force and poor self-cleaning capability of the existing self-cleaning coating and an external wall.

In order to achieve the purpose, the invention provides a graphene external wall panel self-cleaning coating which comprises the following components in parts by weight:

preferably, the particle size of nano silica ions in the alkaline silica sol is not more than 600nm, the content of silica is 20% -30%, and the ratio of silica to sodium oxide is not less than 40%.

Preferably, the film-forming assistant is one or a mixture of more of zinc oxide, butyl silicate, butyl acetate or sodium methyl silicate.

Preferably, the surfactant is sodium benzenesulfonate.

Preferably, the thickener is hydroxyethyl cellulose, CMC or a mixture of the two; the dispersant is sodium hexametaphosphate; the defoaming agent is tributyl phosphate.

The preparation method of the graphene external wall panel self-cleaning coating comprises the following steps:

s1, adding nano yttrium oxide and nano cerium oxide into a certain amount of deionized water, and performing ultrasonic uniform dispersion for 40-60 minutes at the rotating speed of 1000-2000rpm to prepare yttrium-cerium composite ceramic nano liquid;

s2, adding graphene into a certain amount of deionized water, adding a certain amount of ethanol solution into the deionized water, performing ultrasonic uniform dispersion for 90-180 minutes at the rotating speed of 1000-2000rpm, and evaporating ethanol to prepare graphene dispersion liquid;

s3, adding a film forming agent into a reaction kettle, adding a certain amount of deionized water, stirring, then sequentially adding a surfactant, a thickening agent, a dispersing agent and a defoaming agent, stirring uniformly, then slowly adding alkaline silica sol into the reaction kettle, adding a styrene acrylate emulsion, a graphene dispersion liquid and a yttrium cerium composite ceramic nano liquid, stirring uniformly, and grinding and dispersing by a grinder for 1-2 hours;

s4, adding the pigment and all the deionized water into the grinding material, and stirring and mixing uniformly at the rotating speed of 800-1200rpm to obtain the coating.

The graphene external wall panel self-cleaning coating and the preparation method thereof have the advantages and positive effects that:

1. when the silica sol loses moisture, monomer silicic acid is gradually polymerized to form high polymer silica gel, colloid molecules are enlarged along with the evaporation of the moisture, and finally a coating film with a "-Si-O-Si-O-" net structure is formed, so that various dust in the air is difficult to adhere to the coating film, and the anti-pollution capability is strong. Sodium oxide (Na) in silica sol₂O) content is low, and the silica sol does not dissolve again once formed, so that the water resistance and heat resistance are good. Silica (Si) in silica sol₂O), has stronger penetrability to the base layer, can permeate into the base layer through a capillary, and can react with calcium hydroxide in the concrete base layer to generate calcium silicate, so that the coating has stronger binding power.

2. A certain amount of styrene acrylate emulsion is added into the coating, so that styrene acrylate molecules are uniformly distributed in gaps of a "-Si-O-Si-" net structure, residual hydrophilic groups in a coating film are shielded, and meanwhile, the shrinkage of the coating can be buffered during cold and hot alternation, and the coating has certain elasticity.

3. The graphene serving as nano-level particles can fill gaps or cavities of the coating, can effectively achieve the filling effect, and can isolate water and oxygen to enable the surface to be completely separated from the outside. Due to the surface effect of the graphene, the contact angle between the graphene and water is large, the wettability of the graphene to water is poor, and the self-cleaning effect of the coating is improved.

4. The yttrium cerium oxide composite ceramic nano liquid is prepared by dispersing nano yttrium oxide and nano cerium oxide and then modifying the dispersed nano yttrium oxide and nano cerium oxide according to a ratio, and the yttrium cerium composite ceramic nano liquid and graphene are added into the coating, so that the simulation is carried out by utilizing the lotus leaf hydrophobic principle, and the invasion of dust and oil stains can be effectively prevented.

The technical solution of the present invention is further described in detail by the following examples.

Detailed Description

The graphene external wall panel self-cleaning coating comprises the following components in parts by weight:

the particle size of nano silicon dioxide ions in the alkaline silica sol is not more than 600nm, the content of silicon dioxide is 20-30%, and the proportion of silicon dioxide and sodium oxide is not less than 40%.

The film forming assistant is one or a mixture of more of zinc oxide, butyl silicate, butyl acetate or sodium methyl silicate.

The surfactant is sodium benzene sulfonate.

The thickener is hydroxyethyl cellulose, CMC or the mixture of the hydroxyethyl cellulose and the CMC; the dispersant is sodium hexametaphosphate; the defoaming agent is tributyl phosphate.

The pigment may be carbon black, titanium dioxide, indigo or other pigments.

The preparation method of the graphene external wall panel self-cleaning coating comprises the following steps:

s1, adding the nano yttrium oxide and the nano cerium oxide into a certain amount of deionized water, and performing ultrasonic uniform dispersion for 40-60 minutes at the rotating speed of 1000-2000rpm to prepare the yttrium-cerium composite ceramic nano liquid.

S2, adding graphene into a certain amount of deionized water, adding a certain amount of ethanol solution into the deionized water, performing ultrasonic uniform dispersion for 90-180 minutes at the rotating speed of 1000-2000rpm, and evaporating ethanol to prepare graphene dispersion liquid; the addition of the ethanol solution can improve the dispersibility of the graphene.

S3, adding the film forming agent into a reaction kettle, adding a certain amount of deionized water, stirring, then sequentially adding the surfactant, the thickening agent, the dispersing agent and the defoaming agent, stirring uniformly, then slowly adding the alkaline silica sol into the reaction kettle, adding the styrene acrylate emulsion, the graphene dispersion liquid and the yttrium cerium composite ceramic nano liquid, stirring uniformly, and grinding and dispersing by a grinder for 1-2 hours.

S4, adding the pigment and all the deionized water into the grinding material, and stirring and mixing uniformly at the rotating speed of 800-1200rpm to obtain the coating.

Silica sol is used as a base material, pigment and various assistants are matched to prepare silica sol inorganic high-molecular paint, when the silicon solution loses moisture, monomer silicic acid is gradually polymerized to form high polymer silica gel, colloid molecules are enlarged along with the evaporation of the moisture, and finally a coating film with a "-Si-O-Si-O-" net-shaped structure is formed. Sodium oxide (Na) in silica sol₂O) content is low, and the silica sol does not dissolve again once formed, so that the water resistance and heat resistance are good. Silica (Si) in silica sol₂O), has stronger penetrability to the base layer, can permeate into the base layer through a capillary, and can react with calcium hydroxide in the concrete base layer to generate calcium silicate, so that the coating has stronger binding power.

The volume of the silica sol is greatly shrunk in the film forming process, and a coating film is easy to crack. A certain amount of styrene acrylate emulsion is added into the coating, so that styrene acrylate molecules are uniformly distributed in gaps of a "-Si-O-Si-" net structure, residual hydrophilic groups in a coating film are shielded, and meanwhile, the shrinkage of the coating can be buffered during cold and hot alternation, and the coating has certain elasticity.

The graphene serving as nano-level particles can fill gaps or cavities of the coating, can effectively achieve the filling effect, and can isolate water and oxygen to enable the surface to be completely separated from the outside. The contact angle of graphene and water is large due to the surface effect of graphene, wettability of water is poor, moisture is hardly absorbed by the graphene, the graphene isolates the contact of water and a substrate, and the self-cleaning effect of the coating is improved.

The yttrium cerium composite ceramic nano liquid is prepared by modifying nano yttrium oxide and nano cerium oxide according to a ratio after the nano yttrium oxide and the nano cerium oxide are dispersed, the yttrium cerium composite ceramic nano liquid and graphene are added into the coating, and the simulation is carried out by utilizing the principle of lotus leaf drainage, so that the invasion of dust and oil stains can be effectively prevented, the dust and the oil stains can be easily taken away in the process of wind blowing or vibration, the surface of the coating is kept clean, and the self-cleaning effect of the coating is improved.

The present invention will be further described with reference to specific examples, which are provided to illustrate specific embodiments and specific procedures based on the technical solution, but the scope of the present invention is not limited to the examples. The ingredients of the coatings of examples 1-4 are shown in the following table:

detecting the contact angle of the self-cleaning coating and water in the embodiment; uniformly spreading carbon black on the surface of the coating, inclining the surface of the coating by 45 degrees, sucking 0.3ml of distilled water by a sample injector to drop to the upper end of the test surface, and performing a dust collection experiment on the coating; detecting the surface morphology of the coating by adopting a Scanning Electron Microscope (SEM) and an AFM; the adhesion and impact resistance of the coating are detected; the results are set forth in the following table:

in conclusion, the self-cleaning coating for the graphene external wall panel and the preparation method thereof have the advantages of large contact angle, poor dust collecting capacity, and good coating adhesion and impact resistance.

Therefore, the graphene external wall panel self-cleaning coating and the preparation method thereof can solve the problems of low binding force and poor self-cleaning capability of the existing self-cleaning coating and an external wall.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the invention without departing from the spirit and scope of the invention.