| The application of epoxy resin is in many fields, because it has the excellentperformance. But it is only soluble in organic solvents not in water, so when epoxy resin isapplied, volatile organic compounds (VOC) diffusion can’t be controlled to pollute theenvironment.Waterborne epoxy system has completely solved the impact on the environment.But water resistance, resistance to heating and thermal stability are poor. However, thesilicone has its own characteristics, good heat resistance, and soft molecular chain; it iscombined with polymer easier and became larger crosslinking density copolymer. In thisarticle, to improve its performance, silicone is introduced into the aqueous epoxy system. Firstof all, silicone oil containing the hydrogen、Vinyl triethoxy silane and Allyl glycidyl etherreact addition to make organosilicon adduct including epoxy groups;epoxy-amine adduct issealed by mixed organosilicon adduct and different sealing end agent as blocking agent,finally it is made neutralization and salt to silicone modified water epoxy resin curingagent.This experiment determines the optimum synthesis process by changing reactionconditions as the material ratio, reaction time, reaction temperature to investigate reaction’sactive hydrogen content, epoxy groups opening rate, amine value. Mixing the preparedmodified curing agent with epoxy resin cure and form film. Epoxy resin and different cappingagent blocked curing agent are mixed in different ratio and the cured is tested performance.The each step product’s structure is observed by infrared spectrum analysis, found theirchanges, the reaction extent is identified; it can determine whether the curing reaction iscompleted according to this method again. By means of differential scanning calorimetry andthermal gravimetric analysis the thermal stability of cured is analyzed. The active hydrogenconversion rate of the hydrosilylation that hydrosilylation reaction is at85℃for7h accordingto reaction material ratio1:1reaches the maximum; when the end capping agent is themixture of the silicone adducts and AGE in proportion to0.05:0.95, reaction condition is at75℃for3h, the stability of the prepared modified curing agent is good. The pencil hardnessof the cured that it and epoxy resin cure in proportion to1.1:1is4H, the adhesion is5B, theflexibility is1, the tensile shear strength of10.70MPa, the resistance to water、acid and alkaliare enhanced, at the same time the surface of film is uniform. The cured of glass transition temperature is higher40℃than the cured containing0silicone, the temperature is368.94℃at the rate of the maximum weight loss. |
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