The Synthesis Of Epoxy/Polyether Oligomer And Its UV Waterborne Coating System Preparation

Oligomers is the major component in the UV curing system, with its high viscosity, diluted monomer had to be added into the UV coating system to modify its rheology behavior and viscosity, however, the monomer is toxic and irritating to human, thus restrict the development of UV curing technology. UV waterborne technology is the combination of the advantage of both traditional UV technology and water-based coating technology. It has been developed rapidly in recent years and becoming one of the main developing directions for coating area by its environment friendly technology and no effect on human’s health.In this paper, allyl alcohol polyether with multi-functional group was selected to synthesize with epoxy resin, the final synthesis products was applied to prepare the UV water-based coating.Firstly, the synthesis performance of different catalysts was studied, BF₃·OEt₂ had the highest catalytic activity, but the number of C=C group decreased remarkably during the reaction, on the contrary, the blend catalyst maintained good performance on epoxy group reaction, at the same time, effectively reduce the losses of C=C with light color products, it is easily to meet the application requirements. Its viscosity and temperature dependence were in line with the Arrhenius equation, combined with characterization by FT-IR and iodimetry drop method.The synthesis product had good emulsifying capacity, when the amount is over 10wt%, the system turned to light yellow transparent stable solution. The higher the ratio, the better system stability.Emulsifier added into the system within a certain amount was good for curing performance of the system, the best amount was 15wt%.The system could reach its phase reverse point while 23wt% of deionized water was added in, however, it decreased the curing performance. The gel content of the cured film droped from 94.3% to 91.7%, hardness reduced to B from 3H.Cured film made by blend catalyst had the best curing performance with 93.2% of its gel content, hardness 4H, better than any curing performance synthesized by single catalysts and also better than the system without synthesized product.The higher level of ethoxylation for the acrylic monomers that were put into the system, the larger its molecular weight, the better system’s curing performance. The cured film could reach its best curing performance when 15wt% of acrylic monomer was added into the system.