Preparation And Properties Of Silicone Modified Acrylic Coatings For Low Temperature Andanti-fog

Polycarbonate(PC)is a widely used engineering plastics.Polycarbonate material has excellent physical and mechanical properties,but its hardness is generally less than 2H and low temperature fog performance is poor which restrict its practical application.In view of these two problems,this subject developed two new types of coatings: silicone transparent hardening coating and silicone modified acrylic transparent lowtemperature anti-fogging coating.The formulation and construction process were explored,and the coating properties were tested.First,the new silicone hardening transparent coating.At low temperature,ethyl orthosilicate and methyl trimethoxysilane were used as the main film-forming materials,and KH560 coupling agent was used as the adhesion promoter.The mixed solvent are isopropyl alcohol and ethylene glycol ether and acetic acid solution with pH=4 was used as hydrolysis catalyst to catalyze hydrolysis.After 4h pre-condensation and 24 h aging,the coating was prepared.With film-forming components and adhesion additives separate hydrolysis,precise control of the hydrolysis degree,combined with the unique base coating and curing process,coating on the PC board increase after hard transparent silicone coating hardness can be up to 5 h,adhesion level 0,light transmittance up to 93%,glass transition temperature of 70 ?.Second,the new silicone modified acrylic transparent low temperature anti-fog coating.Because acrylic monomers contain highly active carbon-carbon double bonds and a lot of hydrophilic functional groups.The acrylic resin modified by organic silicon can balance the hydrophilic property of acrylic resin and the mechanical property of organic silicon.In this paper,the KH-570 modified with butyl acrylate,methyl acrylic acid armour grease acrylic resin as the main film-forming material.By introducting hydroxy ethyl methacrylate,2-acrylamide-methyl propane sulfonic acid,and homemade hydrophilic small molecules,realize hydrophilization of coating.After polymerization,hydrolysis,aging process,the coating was prepared successfully.When the base material surface temperature drops to the water vapor dew point temperature,little drops of water are able to form a layer on the surface of the unfolding of water membrane,so as to realize high temperature prevent mist(85 ?),and low temperature prevent mist(40 ?),can be used at least 100 times repeated,coating adhesion level 0,Light transmittance over 90%,the relative roughness of 3.5 nm,contact Angle is 11.7 °,glass transition temperature is 65 ?,show the better performance of coating.In a word,new silicone hardening transparent coating and organosilicon modified acrylic transparent low-temperature fog-proof coating are helpful for the popularization and application of Windows PC in dust-proof protective clothing.