Preparation And Property Study Of A New Water-based Strippable Coating

Water-based strippable coating is a environmentally friendly paint which is used to the surface of the objects for temporary protection. This paint can brush, spray and dry quickly, which can keep the object away from the physical and chemical damage, and it can adapt to the complex shape or precision instrument parts. At last, it can be torn off completely. Due to the its excellent performance, acrylate polymer has a larger usable range than polyurethane resin, and more appropriate as main sticky material for a water-based strippable coatingThe first step of the paper is to synthesize the waterborne acrylate emulsion, Choose the appropriate monomers, adjust the ratio of the ration of monomer, temperature, the dosage and ratio of the emulsifying agent, and the dosage of initiator to get the emulsion which has the excellent film-forming performance and stable. Optimized conditions: the ratio of the hard momomer styrol and the soft monomer butyl acrylate is 1:3, temperature 75℃, the dosage of anionic emulsifier lauryl sodium sulfate(SDS) and the non-ionic emulsifier(OP-10) is 4% of the total monomer, and the ratio is 2:1, the initiator potassium peroxodisulfate 0.5%, and a small amount of sodium bicarbonate buffer reagent. Then analyze the production through the tests of infrared spectra, scanning electron microscope, particle size and thermogravimetry. learn the reaction mechanism of the reaction, the functional group, surface topography, thermal decomposition and so on.The second step is to modify the silica sol as the inorganic filler of the water-based strippable coating. By contrast, silane coupling agent γ-glycidoxy propyl trimethoxy silane as modifying agent(KH560) and alcohol as common solvent are the best choices. The reaction condition of the surface modification of the alkaline silica sol is as follows: the dosage of the KH560 is 15% as well as the alcohol, temperature 70℃, p H 9,reaction for 12 h. The average grain diameter of the modified silica sol has a slight increase, and more concentrated distribution, It means the organic silicon contribute to dispersing the particle and getting a homogeneous dispersion system.The last step is preparing the water-based strippable coating and testing it. Add the modified silica sol to the water-based acrylic emulsion, and then use the promoter to achieve obvious the performance improvement and optimization. The best technological process to prepare the water-based strippable coating is adding the agent at every certain time intervals, the dispersant 0.4%, the thickener 0.4%, the flatting agent 0.6% and the coalescing agent 4% to the reactor, dispersing the additives at a high agitation speed, then adding the modified silica sol 6%, when it is medium-high speed dispersed, further mixing the emulsion with the mica dispersion at a medium speed. At the end of the stirring, a certain antifoaming agent 0.8% is added the emulsion,and then add multifunctional additives to stabilize the p H during storage. and colate the coatings to get the best product. The hardness of the final product is 3H, and has a good resistance to water after soaking for 24 h. The particle size of the coating is about 102.1nm. The coating has characteristics of strippable, decontamination and heat-resisting performance.