1： Application of Coupling Agents in Waterborne Coatings
At present, due to the environmental requirements, coatings are gradually changing from oil-based to water-based. Therefore, the application of water-based coatings is much more common than before. Inorganic nanoparticles used in water-based coatings can improve their mechanical properties, weather resistance, and scrub resistance. However, the high surface energy, large specific surface area, and tendency to aggregate of nanoparticles affect their application effectiveness. To improve the dispersibility of inorganic nanoparticles in water-based coatings, coupling agents are used for surface modification. The study investigated the effect of aluminum titanium composite coupling agent modified conductive carbon black on the performance of water-based conductive coatings and their electric heating films. The results showed that compared with the conductive coating prepared by unmodified conductive carbon black, the volume resistivity of the conductive coating prepared by modified conductive carbon black was lower than the former, but the percolation phenomenon occurred later and the adhesion of the conductive coating was enhanced; Scanning electron microscopy shows that the dispersibility of modified conductive carbon black is improved in water-based resins. Compared with the electric heating film prepared by unmodified conductive carbon black, the stability of the resistance value of the electric heating film prepared by modified conductive carbon black is improved under adiabatic and room temperature electrification conditions TiO2 nanoparticles were modified with silane coupling agent and dispersant sodium hexametaphosphate, and were applied to waterborne styrene acrylic lotion coatings. Compared with ordinary water-based coatings, its viscosity is reduced and it is easy to apply; And the comprehensive performance of the coating has been significantly improved, with adhesion level 1, water resistance of 120 hours, alkali resistance of 96 hours, and abrasion resistance exceeding 5000 times. The surface of nano calcium carbonate was modified with 15% water-soluble ethanolamine titanate coupling agent, and the styrene acrylic lotion of exterior wall coating modified by nano calcium carbonate particles with good dispersion was prepared, which greatly improved the water resistance, scrub resistance, stain resistance and other properties of the coating.
2： Application of Coupling Agents in Conductive Coatings
Conductive coatings applied to non-conductive substrates have the ability to conduct current and eliminate static charges. Conductive coatings are usually composed of matrix resin, additives, pigments, conductive fillers, and solvents. After high-speed dispersion and mixing, they are applied to the surface of non-conductive substrates to form a conductive cured film. Research has shown that the addition of coatings increases the electrical resistance of the system, while the addition of coatings reduces the electrical resistance of the system. Among them, the system with a mass fraction of 2.5% shows the greatest reduction in electrical resistance. A modified carbon fiber system conductive coating based on acrylic resin was developed, and the * * * * process conditions for preparing the carbon fiber system conductive coating were determined: the modified carbon fiber/resin mass ratio was 0.7, and the titanium ester coupling agent was used in combination with a pre-treatment dosage of 1% (mass fraction) and a direct addition dosage of 1.5% (mass fraction). The comprehensive performance of the conductive coating prepared was good; At a curing temperature of 50 ℃ for 20 minutes and a coating thickness of 150mm, the surface resistivity reaches 1.02Ω/sq。 Of course, the process flow has a significant impact on the application results of the product.
3： Application of Coupling Agents in Epoxy Anti corrosion Coatings
One important function of coupling agents is to increase the adhesion of coatings. The protective ability of coatings on substrates depends on the adhesion between coatings and substrates. The greater the adhesion between coatings and substrates, the longer the protective effect they provide. Coupling agents, as adhesion promoters, can be directly added to the coating system to improve the adhesion between the coating and the substrate. Research has shown the effect of amino silane coupling agents on the adhesion of epoxy coatings to steel substrates. Research has shown that amino silane coupling agents can hydrolyze to form silicon hydroxyl groups under extremely low water conditions. Coatings with added amino silane coupling agents have chemical bonding with substrates, which can significantly improve the adhesion between coatings and substrates; Compared with pure epoxy coatings, it can increase by 5-6 MPa. Infrared and reflectance infrared analysis show that the coating with amino silane coupling agent has a chemical bond with the steel substrate. Therefore, the silane coupling agent produced by our company is widely used in epoxy anti-corrosion coatings.
