CN-121975398-A - Double-component epoxy low-surface-energy primer-topcoat paint and preparation method thereof

Abstract

The application relates to a two-component epoxy low-surface-energy primer-topcoat paint which comprises, by weight, 150 parts of epoxy resin, 50-100 parts of low-surface-energy filler, 50-100 parts of filler by volume, 10-20 parts of pigment, 1-5 parts of polymethylalkylsiloxane defoamer, 3-10 parts of low-surface-energy auxiliary agent and 30-60 parts of organic solvent, wherein the agent B is an amine epoxy curing agent, when in use, the mixing weight ratio of the agent A to the agent B is that the agent B is=200:10-20, and the two-component epoxy low-surface-energy primer-topcoat paint provided by the application can solve the problem of adhesion reduction of a traditional coating due to enrichment of low-surface-energy components through epoxy resin compounding, low-surface-energy component gradient distribution design and multistage filler collaborative filling, can realize double functions of corrosion prevention and low-surface-energy coating by adopting single-channel coating, and is suitable for complex working conditions such as high altitude, offshore.

Inventors

• GAO JINHUI
• ZHANG HONG

Assignees

• 深圳琼霸科技有限公司

Dates

Publication Date

20260505

Application Date

20260318

Claims (10)

1. 1. The two-component epoxy primer-topcoat paint with low surface energy is characterized by comprising an agent A and an agent B; the agent A comprises the following components in parts by weight: 150 parts of epoxy resin; 50-100 parts of low surface energy filler; 50-100 parts by volume of filler; 10-20 parts of pigment; 1-5 parts of polymethylalkylsiloxane defoamer; 3-10 parts of a low surface energy auxiliary agent; 30-60 parts of an organic solvent; the agent B is an amine epoxy curing agent; when the composition is used, the mixing weight ratio of the agent A to the agent B is that the agent A is the agent B=200:10-20.
2. 2. A two-part epoxy low surface energy primer-topcoat as claimed in claim 1, wherein: the epoxy resin is a mixture of long-chain structural epoxy resin and micromolecular epoxy resin, and is prepared by mixing the long-chain structural epoxy resin and the micromolecular epoxy resin according to any mass ratio.
3. 3. A two-part epoxy low surface energy primer-topcoat as claimed in claim 1, wherein: The low-surface energy filler is at least one selected from polytetrafluoroethylene, nano silicon dioxide and PE wax; Wherein the average particle diameter of the nano silicon dioxide is 10 mu m.
4. 4. A two-part epoxy low surface energy primer-topcoat as claimed in claim 1, wherein: The volume filler is at least three of precipitated barium sulfate with 1000 meshes, 1250-mesh mica powder, talcum powder with 3000 meshes, 1250-mesh silica powder, wollastonite powder with 800 meshes, feldspar powder with 800 meshes and graphite powder with 500 meshes.
5. 5. A two-part epoxy low surface energy primer-topcoat as claimed in claim 1, wherein: The pigment is at least one of iron oxide red, carbon black and titanium white.
6. 6. A two-part epoxy low surface energy primer-topcoat as claimed in claim 1, wherein: the low-surface energy auxiliary agent is at least one of polyether modified organic siloxane copolymer surface auxiliary agent, organic silicon surface treating agent and fluorine modified acrylic ester auxiliary agent.
7. 7. A two-part epoxy low surface energy primer-topcoat as claimed in claim 1, wherein: The organic solvent is at least one of dimethylbenzene and n-butanol.
8. 8. A two-part epoxy low surface energy primer-topcoat as claimed in claim 1, wherein: The amine epoxy curing agent is at least one of modified polyamide, phenolic amide and polyamide.
9. 9. The method for preparing a two-component epoxy primer-topcoat with low surface energy according to any one of claims 1 to 8, comprising the steps of: S10, adding 150 parts by weight of epoxy resin into a reaction kettle, then adding 30-60 parts by weight of organic solvent, uniformly stirring at a high speed, and controlling the mixing temperature to be in a range of 10-40 ℃; s20, sequentially adding 1-5 parts by weight of polymethyl alkyl siloxane, a first part of low surface energy auxiliary agent, 50-100 parts by weight of low surface energy filler, 50-100 parts by weight of volume filler and 10-20 parts by weight of pigment under a continuous stirring state, stirring at a high speed for 0.1-0.5 h, and grinding for 0.5-2 h by using a sand mill; S30, returning the grinding product obtained in the step S20 to a reaction kettle, adding a second part of low-surface-energy auxiliary agent, and stirring at a high speed for 0.1-1 h to obtain an agent A; and S40, taking the amine epoxy curing agent as the agent B, and mixing and uniformly stirring 200 parts by weight of the agent A and 10-20 parts by weight of the agent B when the two-component epoxy primer-topcoat paint is used to prepare the two-component epoxy primer-topcoat paint with low surface energy.
10. 10. The method for preparing the two-component epoxy primer-topcoat with low surface energy according to claim 9, which is characterized in that: the sum of the parts by weight of the low surface energy auxiliary agent of the first part in the step S20 and the low surface energy auxiliary agent of the second part in the step S30 is 3-10 parts.

Description

Double-component epoxy low-surface-energy primer-topcoat paint and preparation method thereof Technical Field The application relates to the technical field of paint, in particular to a double-component epoxy primer-topcoat paint with low surface energy and a preparation method thereof. Background The development process of the marine protective coating gradually evolves from a single anti-corrosion primer to be matched with an anti-fouling finish paint for use, and then the development process is carried out to a bottom surface integrated system which has the functions of corrosion resistance and low surface energy and is explored nowadays. At present, a multilayer coating structure is commonly adopted on ships, wharfs, platforms and other marine structures so as to solve the problems of increased sailing resistance, increased fuel consumption, accelerated structural corrosion and the like caused by marine organism adhesion, and meanwhile, adverse effects of frost-swelling tangential force on structural stability are required to be reduced through a coating in pile foundation engineering of a permanent frozen soil area and a semi-frozen soil area. The key point of the existing protective coating for ocean and frozen soil environments is to combine the adhesion to a substrate and the low surface energy characteristic of the surface of the coating. However, the silicon and fluorine low surface energy components tend to be enriched in the surface layer of the coating in the film forming process, and although the silicon and fluorine low surface energy components are helpful to form a hydrophobic anti-fouling or drag reduction interface, the wettability and chemical bonding capability between the coating and the substrate can be weakened, so that the interlayer adhesive force is low, and the phenomenon of foaming or falling off occurs in long-term service. In addition, the traditional multilayer coating system relates to sequential construction of primer, intermediate coat and finish coat, so that the operation difficulty and the safety risk are increased under complex working conditions such as high altitude or offshore, the integral protection effect is possibly influenced due to the problem of interlayer compatibility, and the challenges of large coating consumption, long construction period, high maintenance cost and the like are brought. Meanwhile, the partial solvent type epoxy paint has higher Volatile Organic Compound (VOC) content which exceeds the current environmental protection standard limit value, and the water-based substitution system can reduce VOC emission, but still has certain restrictions on water resistance, drying speed and comprehensive cost. Disclosure of Invention In order to solve the defects, the application provides a two-component epoxy primer-topcoat paint with low surface energy and a preparation method thereof. The first object of the present application is achieved by the following technical solutions: A two-component epoxy primer-topcoat paint with low surface energy comprises an agent A and an agent B; the agent A comprises the following components in parts by weight: 150 parts of epoxy resin; 50-100 parts of low surface energy filler; 50-100 parts by volume of filler; 10-20 parts of pigment; 1-5 parts of polymethylalkylsiloxane defoamer; 3-10 parts of a low surface energy auxiliary agent; 30-60 parts of an organic solvent; the agent B is an amine epoxy curing agent; when the composition is used, the mixing weight ratio of the agent A to the agent B is that the agent A is the agent B=200:10-20. By adopting the technical scheme, the epoxy resin is used as a film forming main body to provide excellent adhesive force and chemical stability, the low-surface energy filler and the low-surface energy auxiliary agent cooperate to form a gradient distribution structure in the coating, so that the phenomenon that the low-surface energy component is excessively enriched in the surface layer to weaken interface combination with a substrate is avoided, the volume filler fills gaps of an epoxy resin network through multistage particle size collocation, the compactness and mechanical strength of the coating are improved, the polymethyl siloxane defoamer inhibits bubble generation in the construction process, the continuity of the coating is ensured, the low-volatility component is selected as an organic solvent, VOC release is controlled while the construction leveling property is met, and the amine epoxy hardener and the epoxy resin are crosslinked to form a three-dimensional network structure, so that the coating is endowed with excellent water resistance, salt fog resistance and frost heaving resistance. Further, the epoxy resin is a mixture of long-chain structural epoxy resin and micromolecular epoxy resin, and is prepared by mixing the long-chain structural epoxy resin and the micromolecular epoxy resin according to any mass ratio. By adopting the technical scheme, the long-chain str