阅读说明：本技术 一种新型聚氨酯防水涂料及其制备方法 (Novel polyurethane waterproof coating and preparation method thereof ) 是由 殷海红 于 2021-01-14 设计创作，主要内容包括：本发明属于防水涂料技术领域,尤其是一种新型聚氨酯防水涂料及其制备方法,解决了现有技术中聚氨酯防水涂料不具备低应力下的快干功能,普遍存在干燥时间较长,导致二次涂布间隔时间长,严重影响了涂装流水线的作业效率的问题,所述新型聚氨酯防水涂料,包括以下原料：水性聚氨酯40-60份、丙烯酸乳液20-30份、有机膨润土10-20份、改性剂5-12份、溶剂30-50份、邻苯二甲酸二丁酯3-5份、分散剂1-3份、消泡剂2-4份。本发明制备工艺简单,制备条件温和,原料简单易得,所得防水涂料干燥时间短、附着力强,涂膜柔韧性好,抗冲击性好,耐候性好,且具有良好的保光保色性。(The invention belongs to the technical field of waterproof coatings, in particular to a novel polyurethane waterproof coating and a preparation method thereof, which solve the problems that in the prior art, the polyurethane waterproof coating does not have a quick-drying function under low stress, the drying time is long, the secondary coating interval time is long, and the operation efficiency of a coating production line is seriously influenced, and the novel polyurethane waterproof coating comprises the following raw materials: 40-60 parts of waterborne polyurethane, 20-30 parts of acrylic emulsion, 10-20 parts of organic bentonite, 5-12 parts of modifier, 30-50 parts of solvent, 3-5 parts of dibutyl phthalate, 1-3 parts of dispersant and 2-4 parts of defoaming agent. The preparation method disclosed by the invention is simple in preparation process, mild in preparation conditions, simple and easily available in raw materials, short in drying time, strong in adhesive force, good in film flexibility, good in impact resistance and weather resistance, and good in light and color retention.)

1. The novel polyurethane waterproof coating is characterized by comprising the following raw materials in parts by weight: 40-60 parts of waterborne polyurethane, 20-30 parts of acrylic emulsion, 10-20 parts of organic bentonite, 5-12 parts of modifier, 30-50 parts of solvent, 3-5 parts of dibutyl phthalate, 1-3 parts of dispersant and 2-4 parts of defoaming agent.

2. The novel polyurethane waterproof coating according to claim 1 is characterized by comprising the following raw materials in parts by weight: 45-55 parts of waterborne polyurethane, 22-28 parts of acrylic emulsion, 12-18 parts of organic bentonite, 6-10 parts of modifier, 35-45 parts of solvent, 3.5-4.5 parts of dibutyl phthalate, 1.5-2.5 parts of dispersant and 2.5-3.5 parts of defoaming agent.

3. The novel polyurethane waterproof coating according to claim 1 is characterized by comprising the following raw materials in parts by weight: 50 parts of waterborne polyurethane, 25 parts of acrylic emulsion, 15 parts of organic bentonite, 8 parts of modifier, 40 parts of solvent, 4 parts of dibutyl phthalate, 2 parts of dispersant and 3 parts of defoaming agent.

4. The novel polyurethane waterproof coating material as claimed in claim 1, wherein the modifier is prepared by the following method: adding 10-15 parts by weight of zinc oxide and 2-6 parts by weight of triethanolamine oleate soap into a mixed solution consisting of 8-12 parts by weight of toluene and 20-30 parts by weight of water, ultrasonically shaking and mixing for 10-18min at 40-60 ℃, adding 1-2 parts by weight of beta-naphthol and 0.8-1.2 parts by weight of 9-hydroxy phenanthrene, heating to 70-90 ℃, shaking and mixing for 10-18min, uniformly mixing, and drying to obtain the required modifier.

5. The novel polyurethane waterproof paint as claimed in claim 1, wherein the solvent is a mixture of ethyl acetate, glycerol and water in a mass ratio of 1:2: 7.

6. The novel polyurethane waterproofing paint according to claim 1, wherein the dispersant is alumina.

7. The novel polyurethane waterproof coating material as claimed in claim 1, wherein the defoaming agent is a mixture of glycerol polyoxypropylene ether and polydimethylsiloxane in a mass ratio of 1: 1.

8. Process for the preparation of a novel polyurethane waterproofing coating according to any of claims 1 to 7, characterized in that it comprises the following steps:

s1, weighing 40-60 parts of raw material waterborne polyurethane, 20-30 parts of acrylic emulsion, 10-20 parts of organic bentonite, 5-12 parts of modifier, 30-50 parts of solvent, 3-5 parts of dibutyl phthalate, 1-3 parts of dispersant and 2-4 parts of defoaming agent for later use;

s2, adding the aqueous polyurethane and the acrylic emulsion with the specific gravity into a reaction kettle, starting a stirrer, adding a dispersing agent and a solvent, and emulsifying at normal temperature for 1-2 hours to obtain an emulsion;

s3, heating the emulsion obtained in the step S1 to 70-90 ℃, adding the modifier with the specific gravity, stirring and mixing for 20-40min, and uniformly mixing to obtain a modified emulsion;

and S4, controlling the temperature of the modified emulsion to be 85-105 ℃, sequentially adding the organic bentonite, the dibutyl phthalate and the defoaming agent with the specific gravity, and stirring and mixing uniformly to obtain the modified emulsion.

Technical Field

The invention relates to the technical field of waterproof coatings, in particular to a novel polyurethane waterproof coating and a preparation method thereof.

Background

The polymer waterproof coating is generally a waterproof coating prepared by taking a synthetic resin emulsion as a basic film-forming material. As one of the functional building coatings, polymer waterproof coatings have been widely used in recent years in waterproofing works for structural parts such as roofs, basements, kitchens and toilets of buildings, and exterior walls. A water-proof Polyurethane (PU) paint is a new-type high-molecular water-proof material which appears in Europe, America and Japan in the 60 th of 20 th century, and is prepared from the prepolymer whose end group is isocyanate and prepared by the reaction of polyether (ester) polyol and excess diisocyanate as main body, and filler and assistant through adding. The waterproof coating overcomes the defects of the traditional asphalt series waterproof coating and waterproof coiled materials, has the advantages of excellent overall waterproof performance, stable and reliable performance, convenient construction and maintenance, easy regulation of component proportion and the like, can be used for waterproofing and moistureproof of different parts of buildings and plugging in civil engineering, and therefore plays an important role in the building waterproof coating and is favored by the waterproof world at home and abroad.

In the prior art, the polyurethane waterproof coating mainly aims at solving the problems of high permeability, weather resistance, corrosion resistance and the like, does not have a quick-drying function under low stress, and generally has the defects of long secondary coating interval time due to long drying time, and serious influence on the operation efficiency of a coating production line. Therefore, researchers increase the proportion of the drier forcibly on the basis of the existing polyurethane waterproof coating so as to improve the drying speed of the coating. Although the increase of the drier can accelerate the surface drying speed of the coating, the drier can also have certain negative effects on the physical and mechanical properties of the coating and can reduce the surface energy of the coating, so that the stress of the coating is increased, and the compatibility is reduced. Based on the statement, the invention provides a novel polyurethane waterproof coating and a preparation method thereof.

Disclosure of Invention

The invention aims to solve the problems that in the prior art, a polyurethane waterproof coating does not have a quick-drying function under low stress, the secondary coating interval time is long due to long drying time, and the operation efficiency of a coating production line is seriously influenced, and provides a novel polyurethane waterproof coating and a preparation method thereof.

A novel polyurethane waterproof coating comprises the following raw materials in parts by weight: 40-60 parts of waterborne polyurethane, 20-30 parts of acrylic emulsion, 10-20 parts of organic bentonite, 5-12 parts of modifier, 30-50 parts of solvent, 3-5 parts of dibutyl phthalate, 1-3 parts of dispersant and 2-4 parts of defoaming agent.

Preferably, the novel polyurethane waterproof coating comprises the following raw materials in parts by weight: 45-55 parts of waterborne polyurethane, 22-28 parts of acrylic emulsion, 12-18 parts of organic bentonite, 6-10 parts of modifier, 35-45 parts of solvent, 3.5-4.5 parts of dibutyl phthalate, 1.5-2.5 parts of dispersant and 2.5-3.5 parts of defoaming agent.

Preferably, the novel polyurethane waterproof coating comprises the following raw materials in parts by weight: 50 parts of waterborne polyurethane, 25 parts of acrylic emulsion, 15 parts of organic bentonite, 8 parts of modifier, 40 parts of solvent, 4 parts of dibutyl phthalate, 2 parts of dispersant and 3 parts of defoaming agent.

Preferably, the modifier is prepared by the following method: adding 10-15 parts by weight of zinc oxide and 2-6 parts by weight of triethanolamine oleate soap into a mixed solution consisting of 8-12 parts by weight of toluene and 20-30 parts by weight of water, ultrasonically shaking and mixing for 10-18min at 40-60 ℃, adding 1-2 parts by weight of beta-naphthol and 0.8-1.2 parts by weight of 9-hydroxy phenanthrene, heating to 70-90 ℃, shaking and mixing for 10-18min, uniformly mixing, and drying to obtain the required modifier.

Preferably, the solvent is a mixture of ethyl acetate, glycerol and water in a mass ratio of 1:2: 7.

Preferably, the dispersant is alumina.

Preferably, the defoaming agent is a compound agent of glycerol polyoxypropylene ether and polydimethylsiloxane in a mass ratio of 1: 1.

The invention also provides a preparation method of the novel polyurethane waterproof coating, which comprises the following steps:

s1, weighing 40-60 parts of raw material waterborne polyurethane, 20-30 parts of acrylic emulsion, 10-20 parts of organic bentonite, 5-12 parts of modifier, 30-50 parts of solvent, 3-5 parts of dibutyl phthalate, 1-3 parts of dispersant and 2-4 parts of defoaming agent for later use;

s2, adding the aqueous polyurethane and the acrylic emulsion with the specific gravity into a reaction kettle, starting a stirrer, adding a dispersing agent and a solvent, and emulsifying at normal temperature for 1-2 hours to obtain an emulsion;

s3, heating the emulsion obtained in the step S1 to 70-90 ℃, adding the modifier with the specific gravity, stirring and mixing for 20-40min, and uniformly mixing to obtain a modified emulsion;

and S4, controlling the temperature of the modified emulsion to be 85-105 ℃, sequentially adding the organic bentonite, the dibutyl phthalate and the defoaming agent with the specific gravity, and stirring and mixing uniformly to obtain the modified emulsion.

The novel polyurethane waterproof coating provided by the invention has the following beneficial effects:

1. the invention adopts water-based polyurethane and acrylic emulsion as main components, and the water-based polyurethane and acrylic emulsion are dispersed and mixed by adding a dispersant and a solvent, then modified by adding a modifier, and finally mixed with organic bentonite, dibutyl phthalate and a defoaming agent to obtain the required waterproof coating; the preparation method disclosed by the invention is simple in preparation process, mild in preparation conditions, simple and easily available in raw materials, short in drying time, strong in adhesive force, good in film flexibility, good in impact resistance and weather resistance, and good in light and color retention.

2. According to the invention, a mixed solution is formed by toluene and water, zinc oxide, triethanolamine oleate soap, beta-naphthol and 9-hydroxy phenanthrene are added, vibrated, mixed and dried to prepare a modifier, and the modifier is used for modifying the main components formed by aqueous polyurethane and acrylic emulsion, so that the adhesion and impact resistance of a coating film of the coating are effectively improved; the alumina is used as a dispersing agent, and the main components are dispersed and mixed before modification, so that the dispersion effect is effectively improved, the alumina and the modifier play a role in coordination and synergism, the alumina and the modifier are reused, and the adhesion and the impact resistance are obviously improved.

3. The solvent is prepared by mixing ethyl acetate, glycerol and water and is used for mixing and dispersing the main components, the volatilization speed of the solvent is approximate to that of the main components, and the obtained coating film has moderate internal stress, good flexibility and good leveling property.

Detailed Description

The present invention will be further illustrated with reference to the following specific examples.

Example one

The invention provides a novel polyurethane waterproof coating which comprises the following raw materials in parts by weight: 40 parts of waterborne polyurethane, 20 parts of acrylic emulsion, 10 parts of organic bentonite, 5 parts of modifier, 30 parts of solvent, 3 parts of dibutyl phthalate, 1 part of dispersant and 2 parts of defoaming agent.

The preparation method comprises the following steps:

s1, weighing 40 parts of raw material waterborne polyurethane, 20 parts of acrylic emulsion, 10 parts of organic bentonite, 5 parts of modifier, 30 parts of solvent, 3 parts of dibutyl phthalate, 1 part of dispersant and 2 parts of defoaming agent according to parts by weight, and preparing the modifier by the following method: adding 10 parts by weight of zinc oxide and 2 parts by weight of triethanolamine oleate soap into a mixed solution consisting of 8 parts by weight of toluene and 20 parts by weight of water, ultrasonically shaking and mixing for 10min at 40 ℃, adding 1 part by weight of beta-naphthol and 0.8 part by weight of 9-hydroxy phenanthrene, heating to 70 ℃, shaking and mixing for 10min, uniformly mixing, and drying to obtain the required modifier, wherein the solvent is a mixture of ethyl acetate, glycerol and water in a mass ratio of 1:2:7, the dispersing agent is aluminum oxide, and the defoaming agent is a compound agent of glycerol polyoxypropylene ether and polydimethylsiloxane in a mass ratio of 1: 1;

s2, adding the aqueous polyurethane and the acrylic emulsion with the specific gravity into a reaction kettle, starting a stirrer, adding a dispersing agent and a solvent, and emulsifying at normal temperature for 1 hour to obtain an emulsion;

s3, heating the emulsion obtained in the step S1 to 70 ℃, adding the modifier with the specific gravity, stirring and mixing for 20min, and uniformly mixing to obtain a modified emulsion;

and S4, controlling the temperature of the modified emulsion to be 85 ℃, sequentially adding the organic bentonite, the dibutyl phthalate and the defoaming agent with the specific gravity, and stirring and mixing uniformly to obtain the modified emulsion.

Example two

The invention provides a novel polyurethane waterproof coating which comprises the following raw materials in parts by weight: 45 parts of waterborne polyurethane, 22 parts of acrylic emulsion, 12 parts of organic bentonite, 6 parts of modifier, 35 parts of solvent, 3.5 parts of dibutyl phthalate, 1.5 parts of dispersant and 2.5 parts of defoaming agent.

The preparation method comprises the following steps:

s1, weighing 45 parts of raw material waterborne polyurethane, 22 parts of acrylic emulsion, 12 parts of organic bentonite, 6 parts of modifier, 35 parts of solvent, 3.5 parts of dibutyl phthalate, 1.5 parts of dispersant and 2.5 parts of defoaming agent for later use, wherein the modifier is prepared by the following method: adding 11 parts by weight of zinc oxide and 3 parts by weight of triethanolamine oleate soap into a mixed solution consisting of 9 parts by weight of toluene and 22 parts by weight of water, ultrasonically shaking and mixing for 12min at 45 ℃, adding 1.2 parts by weight of beta-naphthol and 0.9 part by weight of 9-hydroxy phenanthrene, heating to 75 ℃, shaking and mixing for 12min, uniformly mixing, and drying to obtain the required modifier, wherein the solvent is a mixture of ethyl acetate, glycerol and water in a mass ratio of 1:2:7, the dispersing agent is aluminum oxide, and the defoaming agent is a compound agent of glycerol polyoxypropylene ether and polydimethylsiloxane in a mass ratio of 1: 1;

s2, adding the aqueous polyurethane and the acrylic emulsion with the specific gravity into a reaction kettle, starting a stirrer, adding a dispersing agent and a solvent, and emulsifying at normal temperature for 1.2h to obtain an emulsion;

s3, heating the emulsion obtained in the step S1 to 75 ℃, adding the modifier with the specific gravity, stirring and mixing for 25min, and uniformly mixing to obtain a modified emulsion;

and S4, controlling the temperature of the modified emulsion to be 90 ℃, sequentially adding the organic bentonite, the dibutyl phthalate and the defoaming agent with the specific gravity, and stirring and mixing uniformly to obtain the modified emulsion.

EXAMPLE III

The invention provides a novel polyurethane waterproof coating which comprises the following raw materials in parts by weight: 50 parts of waterborne polyurethane, 25 parts of acrylic emulsion, 15 parts of organic bentonite, 8 parts of modifier, 40 parts of solvent, 4 parts of dibutyl phthalate, 2 parts of dispersant and 3 parts of defoaming agent.

The preparation method comprises the following steps:

s1, weighing 50 parts of raw material waterborne polyurethane, 25 parts of acrylic emulsion, 15 parts of organic bentonite, 8 parts of modifier, 40 parts of solvent, 4 parts of dibutyl phthalate, 2 parts of dispersant and 3 parts of defoaming agent for later use, wherein the modifier is prepared by the following method: adding 13 parts by weight of zinc oxide and 4 parts by weight of triethanolamine oleate soap into a mixed solution consisting of 10 parts by weight of toluene and 25 parts by weight of water, ultrasonically shaking and mixing for 14min at 50 ℃, adding 1.5 parts by weight of beta-naphthol and 1 part by weight of 9-hydroxy phenanthrene, heating to 80 ℃, shaking and mixing for 14min, uniformly mixing, and drying to obtain the required modifier, wherein the solvent is a mixture of ethyl acetate, glycerol and water in a mass ratio of 1:2:7, the dispersing agent is aluminum oxide, and the defoaming agent is a compound agent of glycerol polyoxypropylene ether and polydimethylsiloxane in a mass ratio of 1: 1;

s2, adding the aqueous polyurethane and the acrylic emulsion with the specific gravity into a reaction kettle, starting a stirrer, adding a dispersing agent and a solvent, and emulsifying at normal temperature for 1.5h to obtain an emulsion;

s3, heating the emulsion obtained in the step S1 to 80 ℃, adding the modifier with the specific gravity, stirring and mixing for 30min, and uniformly mixing to obtain a modified emulsion;

and S4, controlling the temperature of the modified emulsion to be 95 ℃, sequentially adding the organic bentonite, the dibutyl phthalate and the defoaming agent with the specific gravity, and stirring and mixing uniformly to obtain the modified emulsion.

Example four

The invention provides a novel polyurethane waterproof coating which comprises the following raw materials in parts by weight: 55 parts of waterborne polyurethane, 28 parts of acrylic emulsion, 18 parts of organic bentonite, 10 parts of modifier, 45 parts of solvent, 4.5 parts of dibutyl phthalate, 2.5 parts of dispersant and 3.5 parts of defoaming agent.

The preparation method comprises the following steps:

s1, weighing 55 parts of raw material waterborne polyurethane, 28 parts of acrylic emulsion, 18 parts of organic bentonite, 10 parts of modifier, 45 parts of solvent, 4.5 parts of dibutyl phthalate, 2.5 parts of dispersant and 3.5 parts of defoaming agent for later use, wherein the modifier is prepared by the following method: adding 14 parts by weight of zinc oxide and 5 parts by weight of triethanolamine oleate soap into a mixed solution consisting of 10 parts by weight of toluene and 25 parts by weight of water, ultrasonically shaking and mixing for 16min at 55 ℃, adding 1.8 parts by weight of beta-naphthol and 1.1 parts by weight of 9-hydroxy phenanthrene, heating to 85 ℃, shaking and mixing for 16min, uniformly mixing, and drying to obtain the required modifier, wherein the solvent is a mixture of ethyl acetate, glycerol and water in a mass ratio of 1:2:7, the dispersing agent is aluminum oxide, and the defoaming agent is a compound agent of glycerol polyoxypropylene ether and polydimethylsiloxane in a mass ratio of 1: 1;

s2, adding the aqueous polyurethane and the acrylic emulsion with the specific gravity into a reaction kettle, starting a stirrer, adding a dispersing agent and a solvent, and emulsifying at normal temperature for 1.8h to obtain an emulsion;

s3, heating the emulsion obtained in the step S1 to 85 ℃, adding the modifier with the specific gravity, stirring and mixing for 35min, and uniformly mixing to obtain a modified emulsion;

and S4, controlling the temperature of the modified emulsion to be 100 ℃, sequentially adding the organic bentonite, the dibutyl phthalate and the defoaming agent with the specific gravity, and stirring and mixing uniformly to obtain the modified emulsion.

EXAMPLE five

The invention provides a novel polyurethane waterproof coating which comprises the following raw materials in parts by weight: 60 parts of waterborne polyurethane, 30 parts of acrylic emulsion, 20 parts of organic bentonite, 12 parts of modifier, 50 parts of solvent, 5 parts of dibutyl phthalate, 3 parts of dispersant and 4 parts of defoaming agent.

The preparation method comprises the following steps:

s1, weighing 60 parts of raw material waterborne polyurethane, 30 parts of acrylic emulsion, 20 parts of organic bentonite, 12 parts of modifier, 50 parts of solvent, 5 parts of dibutyl phthalate, 3 parts of dispersant and 4 parts of defoaming agent according to parts by weight, and preparing the modifier by the following method: adding 15 parts by weight of zinc oxide and 6 parts by weight of triethanolamine oleate soap into a mixed solution consisting of 12 parts by weight of toluene and 30 parts by weight of water, ultrasonically shaking and mixing for 18min at 60 ℃, adding 2 parts by weight of beta-naphthol and 1.2 parts by weight of 9-hydroxy phenanthrene, heating to 90 ℃, shaking and mixing for 18min, uniformly mixing, and drying to obtain the required modifier, wherein the solvent is a mixture of ethyl acetate, glycerol and water in a mass ratio of 1:2:7, the dispersing agent is aluminum oxide, and the defoaming agent is a compound agent of glycerol polyoxypropylene ether and polydimethylsiloxane in a mass ratio of 1: 1;

s2, adding the aqueous polyurethane and the acrylic emulsion with the specific gravity into a reaction kettle, starting a stirrer, adding a dispersing agent and a solvent, and emulsifying at normal temperature for 2 hours to obtain an emulsion;

s3, heating the emulsion obtained in the step S1 to 90 ℃, adding the modifier with the specific gravity, stirring and mixing for 40min, and uniformly mixing to obtain a modified emulsion;

and S4, controlling the temperature of the modified emulsion to be 105 ℃, sequentially adding the organic bentonite, the dibutyl phthalate and the defoaming agent with the specific gravity, and stirring and mixing uniformly to obtain the modified emulsion.

Comparative example 1

The invention provides a novel polyurethane waterproof coating which comprises the following raw materials in parts by weight: 50 parts of waterborne polyurethane, 25 parts of acrylic emulsion, 15 parts of organic bentonite, 8 parts of modifier, 40 parts of solvent, 4 parts of dibutyl phthalate, 2 parts of dispersant and 3 parts of defoaming agent.

The preparation method comprises the following steps:

s1, weighing 50 parts of raw material waterborne polyurethane, 25 parts of acrylic emulsion, 15 parts of organic bentonite, 8 parts of modifier, 40 parts of solvent, 4 parts of dibutyl phthalate, 2 parts of dispersant and 3 parts of defoaming agent for later use, wherein the modifier is prepared by the following method: adding 13 parts by weight of zinc oxide and 4 parts by weight of triethanolamine oleate soap into a mixed solution consisting of 10 parts by weight of toluene and 25 parts by weight of water, ultrasonically shaking and mixing for 14min at 50 ℃, adding 1.5 parts by weight of beta-naphthol and 1 part by weight of 9-hydroxy phenanthrene, heating to 80 ℃, shaking and mixing for 14min, uniformly mixing, and drying to obtain the required modifier, wherein the solvent is a mixture of ethyl acetate, glycerol and water in a mass ratio of 1:2:7, the dispersant is sulfosuccinate, and the defoamer is a compound agent of glycerol polyoxypropylene ether and polydimethylsiloxane in a mass ratio of 1: 1;

s2, adding the aqueous polyurethane and the acrylic emulsion with the specific gravity into a reaction kettle, starting a stirrer, adding a dispersing agent and a solvent, and emulsifying at normal temperature for 1.5h to obtain an emulsion;

s3, heating the emulsion obtained in the step S1 to 80 ℃, adding the modifier with the specific gravity, stirring and mixing for 30min, and uniformly mixing to obtain a modified emulsion;

and S4, controlling the temperature of the modified emulsion to be 95 ℃, sequentially adding the organic bentonite, the dibutyl phthalate and the defoaming agent with the specific gravity, and stirring and mixing uniformly to obtain the modified emulsion.

Comparative example No. two

The invention provides a novel polyurethane waterproof coating which comprises the following raw materials in parts by weight: 50 parts of waterborne polyurethane, 25 parts of acrylic emulsion, 15 parts of organic bentonite, 8 parts of modifier, 40 parts of solvent, 4 parts of dibutyl phthalate, 2 parts of dispersant and 3 parts of defoaming agent.

The preparation method comprises the following steps:

s1, weighing 50 parts of raw material waterborne polyurethane, 25 parts of acrylic emulsion, 15 parts of organic bentonite, 8 parts of modifier, 40 parts of solvent, 4 parts of dibutyl phthalate, 2 parts of dispersant and 3 parts of defoaming agent for later use, wherein the modifier is prepared by the following method: adding 13 parts by weight of zinc oxide and 4 parts by weight of triethanolamine oleate soap into a mixed solution consisting of 10 parts by weight of toluene and 25 parts by weight of water, ultrasonically shaking and mixing for 14min at 50 ℃, adding 1.5 parts by weight of beta-naphthol and 1 part by weight of 9-hydroxy phenanthrene, heating to 80 ℃, shaking and mixing for 14min, uniformly mixing, and drying to obtain the required modifier, wherein the solvent is a mixture of ethyl acetate, glycerol and water in a mass ratio of 1:2:7, the dispersing agent is aluminum oxide, and the defoaming agent is a compound agent of glycerol polyoxypropylene ether and polydimethylsiloxane in a mass ratio of 1: 1;

s2, adding the aqueous polyurethane and the acrylic emulsion with the specific gravity into a reaction kettle, starting a stirrer, adding a solvent, and emulsifying at normal temperature for 1.5h to obtain an emulsion;

s3, heating the emulsion obtained in the step S1 to 80 ℃, adding the modifier with the specific gravity, stirring and mixing for 30min, adding the dispersant, and continuously and uniformly mixing to obtain a modified emulsion;

and S4, controlling the temperature of the modified emulsion to be 95 ℃, sequentially adding the organic bentonite, the dibutyl phthalate and the defoaming agent with the specific gravity, and stirring and mixing uniformly to obtain the modified emulsion.

Comparative example No. three

The invention provides a novel polyurethane waterproof coating which comprises the following raw materials in parts by weight: 50 parts of waterborne polyurethane, 25 parts of acrylic emulsion, 15 parts of organic bentonite, 40 parts of solvent, 4 parts of dibutyl phthalate, 2 parts of dispersant and 3 parts of defoaming agent.

The preparation method comprises the following steps:

s1, weighing 50 parts of raw material waterborne polyurethane, 25 parts of acrylic emulsion, 15 parts of organic bentonite, 40 parts of solvent, 4 parts of dibutyl phthalate, 2 parts of dispersant and 3 parts of defoaming agent according to parts by weight for later use, wherein the solvent is a mixture of ethyl acetate, glycerol and water in a mass ratio of 1:2:7, the dispersant is aluminum oxide, and the defoaming agent is a compound agent of glycerol polyoxypropylene ether and polydimethylsiloxane in a mass ratio of 1: 1;

s2, adding the aqueous polyurethane and the acrylic emulsion with the specific gravity into a reaction kettle, starting a stirrer, adding a dispersing agent and a solvent, and emulsifying at normal temperature for 1.5h to obtain an emulsion I;

s3, heating the emulsion obtained in the step S1 to 80 ℃, continuing stirring and mixing for 30min, and uniformly mixing to obtain an emulsion II;

s4, controlling the temperature of the emulsion II to be 95 ℃, sequentially adding the organic bentonite, the dibutyl phthalate and the defoaming agent with the specific gravity, and stirring and mixing uniformly to obtain the emulsion.

The comprehensive properties of the novel polyurethane waterproofing coatings prepared in examples one to five and comparative examples one to three were respectively tested, and the following results were obtained:

table 1:

the above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.