阅读说明：本技术 一种低锌含量的水性环氧防腐涂料及其制备方法 (Water-based epoxy anticorrosive paint with low zinc content and preparation method thereof ) 是由 刘明旺 陆平 庄永卿 张桃 陈亮丹 傅人道 徐祖睿 沙马什布 于 2020-08-19 设计创作，主要内容包括：一种低锌含量的水性环氧防腐涂料,所述涂料包括以下组分：60-80重量份的复合树脂、5-10重量份的滑石粉、10-15重量份的填料、5-8重量份的乙二醇丁醚、1-2重量份的聚乙二醇、0.2-0.8重量份的乳化剂、0.8-1.8重量份的分散剂、30-50重量份的锌粉、30-50重量份的固化剂以及0.3-1重量份的改性石墨烯,所述改性石墨烯为石墨烯中加入改性物质得到,所述改性物质和石墨烯的比例为1:99至4:96。一种低锌含量的水性环氧防腐涂料的制备方法,向石墨烯中加入改性物质得到改性石墨烯,进行研磨和第一次超声分散；将涂料组分中固化剂以外的各组分进行第二次超声分散后充分混合高速搅拌,然后研磨分散；加入固化剂继续搅拌。本发明低锌防腐,更绿色环保,效用持久,能够有效防止海水和空气腐蚀。(A water-based epoxy anticorrosive coating with low zinc content comprises the following components: 60-80 parts of composite resin, 5-10 parts of talcum powder, 10-15 parts of filler, 5-8 parts of ethylene glycol butyl ether, 1-2 parts of polyethylene glycol, 0.2-0.8 part of emulsifier, 0.8-1.8 parts of dispersant, 30-50 parts of zinc powder, 30-50 parts of curing agent and 0.3-1 part of modified graphene, wherein the modified graphene is obtained by adding a modified substance into graphene, and the ratio of the modified substance to the graphene is 1: 99-4: 96. A preparation method of a water-based epoxy anticorrosive paint with low zinc content comprises the steps of adding a modified substance into graphene to obtain modified graphene, and carrying out grinding and first ultrasonic dispersion; carrying out secondary ultrasonic dispersion on all components except the curing agent in the coating component, fully mixing and stirring at a high speed, and then grinding and dispersing; adding the curing agent and continuing stirring. The invention has low zinc corrosion resistance, is more environment-friendly, has lasting effect and can effectively prevent seawater and air corrosion.)

1. The water-based epoxy anticorrosive paint with low zinc content is characterized in that: the coating comprises the following components in parts by weight:

the modified graphene is obtained by adding a modified substance into graphene, and the ratio of the modified substance to the graphene is 1: 99-4: 96.

2. The waterborne epoxy anticorrosive paint with low zinc content according to claim 1, characterized in that: the modified substance is polyvinylpyrrolidone.

3. The waterborne epoxy anticorrosive paint with low zinc content according to claim 1, characterized in that:

the composite resin comprises acrylic resin and epoxy resin, wherein the ratio of the acrylic resin to the epoxy resin is 1: 3 to 1: 7;

the filler includes barium sulfate and calcium carbonate.

4. The waterborne epoxy anticorrosive paint with low zinc content according to claim 3, characterized in that: the weight parts of each component are respectively as follows:

5. a preparation method of a water-based epoxy anticorrosive paint with low zinc content is characterized by comprising the following steps:

s1: adding a modified substance into graphene to obtain modified graphene, wherein the ratio of the modified substance to the graphene is 1: 99-4: 96, and then grinding and first ultrasonic dispersion are carried out;

s2: performing secondary ultrasonic dispersion on 60-80 parts by weight of composite resin, 5-10 parts by weight of talcum powder, 10-15 parts by weight of filler, 5-8 parts by weight of ethylene glycol monobutyl ether, 1-2 parts by weight of polyethylene glycol, 0.2-0.8 part by weight of emulsifier, 0.8-1.8 part by weight of dispersant, 30-50 parts by weight of zinc powder and 0.3-1 part by weight of modified graphene, fully mixing, stirring at high speed, and then grinding and dispersing;

s3: adding 30-50 parts by weight of curing agent and continuing stirring.

6. The preparation method of the water-based epoxy anticorrosive paint with low zinc content according to claim 5, characterized in that the time of the second ultrasonic dispersion is 2 hours; the high speed stirring time is 2 hours.

7. The preparation method of the water-based epoxy anticorrosive paint with low zinc content according to claim 5, characterized in that: the modified substance is polyvinylpyrrolidone.

8. The preparation method of the water-based epoxy anticorrosive paint with low zinc content according to claim 5, characterized in that:

the composite resin comprises acrylic resin and epoxy resin, wherein the ratio of the acrylic resin to the epoxy resin is 1: 3 to 1: 7;

the filler includes barium sulfate and calcium carbonate.

9. The preparation method of the water-based epoxy anticorrosive paint with low zinc content according to claim 8, characterized in that: 60 parts of epoxy resin; 12 parts by weight of acrylic resin; 7.5 parts of talcum powder; 6 parts of barium sulfate; 7.5 parts by weight of calcium carbonate; 6 parts of ethylene glycol butyl ether; 1.5 parts by weight of polyethylene glycol; 0.5 part by weight of emulsifier; 1.2 parts by weight of a dispersant; 40 parts of zinc powder; 36 parts of curing agent; 0.6 part by weight of modified graphene.

Technical Field

The invention relates to the field of coatings, in particular to a water-based epoxy anticorrosive coating with low zinc content and a preparation method thereof.

Background

In the last 50 s of the century, zinc rich primers were developed in the united states. In 1960, our country also began to touch and use zinc rich primers which were applied to the rails to preserve them. The zinc-rich primer is an anticorrosive paint with a large amount of zinc powder added into a film-forming material. After long-time continuous exploration and development, the variety and the yield of the zinc-rich primer are greatly improved. In 2013, the dosage of the zinc-rich primer in China is about 25.5 ten thousand tons, which accounts for about fifteen percent of the total dosage of the heavy-duty anticorrosive paint. The zinc-rich primer has high-efficiency anti-corrosion performance, so that the paint can be rapidly developed and widely applied in the global range.

The zinc powder content in the dry film of the zinc-rich coating is classified into three grades in international standards:

the zinc powder content in the first grade dry film is more than or equal to 85 percent; the content of zinc powder in the second grade dry film is 77-85%; the content of the third grade dry film zinc powder is 65-77%. And ISO12944 specifies a minimum zinc dust content of 80% in epoxy zinc rich primers.

The higher zinc powder content is specified because steel exposed in a corrosive environment, if the zinc content in the zinc-rich primer is low, the particle zinc powder cannot form a complete zinc powder layer, and the cured epoxy resin has poor conductivity, so that the chemical protection effect of the zinc powder is greatly hindered, and the cathode protection effect of the zinc-rich primer on the steel is influenced. But not the more the zinc content the better. The content of zinc powder is too high, the resin content in the natural zinc-rich primer is reduced, film forming matters are reduced, and the adhesive force between a paint film and steel is reduced. Therefore, once water or the like penetrates the surface of the zinc powder, the volume increases, and the possibility of blistering of the coating becomes high. Meanwhile, the high zinc powder content also causes a series of other problems, such as severe bottom sinking phenomenon easily generated in the storage process; when the hot working such as electric welding and cutting is carried out, a large amount of zinc oxide is released, and the zinc fever and the like are easily generated by workers. Meanwhile, the excessive zinc powder in long-term storage can cause bottom sinking phenomenon, and the paint film performance is seriously influenced.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide the water-based epoxy anticorrosive paint with low zinc content and the preparation method thereof, which have the advantages of low zinc corrosion resistance, greenness, environmental protection, lasting effect and capability of effectively preventing seawater and air corrosion.

The purpose of the invention is realized by the following technical scheme:

a water-based epoxy anticorrosive paint with low zinc content comprises the following components in parts by weight:

the modified graphene is obtained by adding a modified substance into graphene, and the ratio of the modified substance to the graphene is 1: 99-4: 96.

Graphene is a planar two-dimensional solid material in a hexagonal shape like a honeycomb arrangement. Has very excellent conductivity, flexibility, mechanical strength and the like. The hexagons are formed by sp2 hybridization of a C — C single bond, only one carbon atom thick. The graphene has a unique lamellar structure, so that the graphene can be used as a filler like scaly mica powder, a glass flake and the like, and is applied to an anticorrosive coating to play a certain role of an isolation barrier, so that the permeation of corrosive media and oxygen is hindered. In addition, due to the excellent physical and chemical properties of graphene, such as good conductivity, excellent mechanical properties, strong shielding performance and strong hydrophobicity of graphene, graphene becomes an ideal filler of epoxy resin coatings. The addition of the graphene can reduce the medium permeability of the anticorrosive paint, improve the conductivity of the low-zinc epoxy resin paint and improve the corrosion resistance of the paint.

Although a large amount of zinc powder in the zinc-rich primer provides good anticorrosion capability for the coating, the zinc-rich primer is easy to cause harm to human bodies and the environment in use. The lamellar structures of the graphene are stacked and staggered layer by layer, a labyrinth shielding structure can be formed in the coating, infiltration, permeation and diffusion of corrosive media can be effectively inhibited, and the physical barrier property of the coating is improved. The excellent conductivity of the graphene can also play a role of a conductive path in the coating, so that the cathodic protection capability of the anticorrosive coating is improved.

Further, the modified substance is polyvinylpyrrolidone. The graphene is not good in dispersibility in the epoxy resin paint, is not uniform in dispersion, and is easy to cause the paint to agglomerate and not to be attractive. The invention adopts the addition of PVP polyvinylpyrrolidone to modify the graphene, improves the dispersibility of the graphene and prevents the coating from caking.

Further, the composite resin comprises acrylic resin and epoxy resin, wherein the ratio of the acrylic resin to the epoxy resin is 1: 3 to 1: 7; the composite resin contains acrylic resin, so that the toughness of the coating is enhanced;

the filler includes barium sulfate and calcium carbonate.

Further, the weight parts of the components are respectively as follows:

a preparation method of a water-based epoxy anticorrosive paint with low zinc content comprises the following steps:

s1: adding a modified substance into graphene to obtain modified graphene, wherein the ratio of the modified substance to the graphene is 1: 99-4: 96, and then grinding and first ultrasonic dispersion are carried out;

s2: performing secondary ultrasonic dispersion on 60-80 parts by weight of composite resin, 5-10 parts by weight of talcum powder, 10-15 parts by weight of filler, 5-8 parts by weight of ethylene glycol monobutyl ether, 1-2 parts by weight of polyethylene glycol, 0.2-0.8 part by weight of emulsifier, 0.8-1.8 part by weight of dispersant, 30-50 parts by weight of zinc powder and 0.3-1 part by weight of modified graphene, fully mixing, stirring at high speed, and then grinding and dispersing;

s3: adding 30-50 parts by weight of curing agent and continuing stirring.

Further, the time of the second ultrasonic dispersion is 2 hours; the high speed stirring time is 2 hours.

Further, the modified substance is polyvinylpyrrolidone.

Further, the composite resin comprises acrylic resin and epoxy resin, wherein the ratio of the acrylic resin to the epoxy resin is 1: 3 to 1: 7;

the filler includes barium sulfate and calcium carbonate.

Further, 60 parts by weight of an epoxy resin; 12 parts by weight of acrylic resin; 7.5 parts of talcum powder; 6 parts of barium sulfate; 7.5 parts by weight of calcium carbonate; 6 parts of ethylene glycol butyl ether; 1.5 parts by weight of polyethylene glycol; 0.5 part by weight of emulsifier; 1.2 parts by weight of a dispersant; 40 parts of zinc powder; 36 parts of curing agent; 0.6 part by weight of modified graphene.

The invention has the beneficial effects that:

the low-zinc anticorrosive paint is green and environment-friendly, has lasting effect, and can effectively prevent seawater and air corrosion.

Drawings

FIG. 1 shows the results of a paint film adhesion test;

FIG. 2 shows the results of corrosion resistance tests on paint films;

FIG. 3 is a polarization curve of a paint film coating;

FIG. 4 is an impedance spectrum of a paint film coating.

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It is to be noted that the features in the following embodiments and examples may be combined with each other without conflict.

It should be noted that the drawings provided in the following embodiments are only for illustrating the basic idea of the present invention, and the components related to the present invention are only shown in the drawings rather than drawn according to the number, shape and size of the components in actual implementation, and the type, quantity and proportion of the components in actual implementation may be changed freely, and the layout of the components may be more complicated.