| With the development of science and technology, people tend to pay more emphasize on environment-protection and energy-saving. It is the consensus that the development directions for coatings are high solid content coatings, waterborne coatings and radiation-curable coatings. Waterborne UV-curable systems have many advantages, such as non-contamination, non-toxicity, non-skin irritation and safety of production. It becomes an attractive research all over the world.Biphenol A epoxy acrylate has the hydroxide radical on its molecular chains which give it good polarity. This property make it have superior adhesive force and wettability to the surface of the materials. Meanwhile, the molecular chain of the epoxy polymer has many functional group: stable C-C bonds and ether linkage, which give the resin good chemical resistance; the benzene rings, which endow the resin with preferable rigidity, strength and thermal stability. Moreover, resins with vinyl could polymerize under radiation or with the addition of peroxide initiator, could form an insoluble and none-fused network with space structure. These above excellent properties make biphenol epoxy-acrylate became one of the most applicable UV-curable waterborne prepolymer.Epoxy acrylic resin (EA) was synthesized from biphenol A epoxy resin and acrylic acid, waterborne UV-curing Epoxy acrylic resin(EB) was synthesized through the reaction of EA and maleic anhydride. After neutralization by alkali, the UV-curable waterborne epoxy-acrylate resins were prepared. And then, aiming at conquering the drawback of high viscosity of the resins, viscosity-reducing modification was made using several kinds of diluents. Finally, organic silicone was introduced into the resins. The UV-curable waterborne epoxy-acrylate resins with high solid content and low viscosity modified with organic silicone were achieved.Firstly, the biphenol epoxy acrylate (EA) was synthesized using E-51 and acrylate; Then, the EA was modified with maleic anhydride to introduce the caboxyl into the molecular chains; the effect of reaction temperature of the system were discussed and the dynamical equation of EA synthesis was investigated. The effect of different kind and content of catalyst, inhibitor on the reaction and product were discussed. Additionally, the resins structure was characterized by FT-IR.Secondly, aiming at the drawback (high visicosity, bad frangibility and low flexibility) of the resins, modified the resins with a series of epoxy diluents(diglycidyl ether of ethylene glycol, diethylene glycol diglycidol ether, hexanediol diglycidyl ether, polypropylene glycol diglycidyl ether, diglycidyl ether of polyethyleneglycol, trimethylolpropane triglycidyl ether) at different molar ratio (1∶2, 1∶1, 2∶1). A fter m odification, the viscosity of resins w ere reduced largely. The viscosity-reducing effects of different diluents were discussed as well as their effects on the mechanical properties of the cured films. The effects of different kind and content of the neutralizing agents, photo initiator and active monomer on the water-solubility, water resistance and mechanical properties of the resins.Thirdly, at the target to increase the water-resistance and comprehensive mechanical properties of the resins, the epoxy-acrylate containing carboxyl was modified by silicone addictives using neutralizing method. The neutralizing agents was prepared using organic base and amino silicone oil (amino silicone end) with low molecular weight, reacting with the carboxyl in the resins to introduce the silicone element into the product. The effects on the water solubility of the resins, water-resistance and mechanical properties with different kind and the content of organic silicone addictives were investigated. The effect of UV curing time on the conversion of double bond were studied using FT-IR. Additionally, the thermal property of the cured films were discussed using DSC.
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