| Bisphenol-A epoxy acrylate is widely used with its excellent adhesive force, corrosion resistance, rigidity and thermal stability, the traditional synthesis method of bisphenol-A epoxy acrylate always results gelling due to the high viscosity of the reaction system or the inadequate mixing during the synthesis, then, the way of adding benzene or toluene into the reaction vessel to reduce the viscosity of epoxy acrylate was proposed, such production method has been gradually applied in industry, howere, this production process is complicated for that the benzene or toluene should be removed by distilloing after reaction.N-butyl glycidyl ether (commonly called EPG660) is one kind of epoxy compounds with very low viscosity, which can lower the viscosity of the reaction system when added into the synthesis system of bisphenol-A epoxy acrylate. In this thesis, one new method of adding laboratory-made EPG660 ioto the reaction vessel as diluent to synthesize one novel epoxy acrylate was proposed. The main research contents and results are as follows:Firstly, EPG660 was prepared with butanol and epichlorohydrin as raw materials, boron trifluoride etherate as cataly and sodium hydroxide as closed-loop agent. The effect of catalyst amount, reaction temperature and feed ratio of the raw materials on the yield and the epoxy value was studied, the best reaction conditions were as follows:the content of boron trifluoride etherate was 0.4wt%, n(epoxy chloropropane): n(n-butanol)=1.8:1, n(NaOH):n(n-butanol)=1.4:1, the temperature of cyclical reaction was30℃.Secondly, novel UV-curable prepolymer was synthesized with E-51/EPG660 mixture as raw material, the effect of catalyst, reaction temperature and inhibitor on the conversion rate, the viscosity of the system and the appearance of the product was studied. The optimum reaction conditions were as follows:the catalyst was tetrabutyl ammonium bromide, content of which was 1.0 wt%, reaction temperature was 105℃, the inhibitor was 4-methoxyphenol, content of which was 0.2 wt%. Besides, effect of different feed ratio of E-51 and EPG660 on the synthesis rate and the final product was studied, the results showed that the addition of EPG660 into the systm effectively reduced the viscosity of the reaction system and increasd the efficiency of the synthesis, and he product can be coated directly for its low viscosity when the feeding ratio of E-51 and EPG660 was 5:1; The resin structure before and after reaction was analyzed by FT-IR.Thirdly, UV-curing coatings were prepared by new epoxy acrylate synthetized by E-51/EPG660 mixture after the photoinitiator was added. The results indicated that the best photoinitiator was the one compounted by 184 and BP, the content of which was 4wt%, the optimum irradiation distance should be 5cm～10cm, optimum irradiation time should be more than 30s; The effect of the addition of EPG660 during the reaction of prepolymer on the properties of UV-curing coatings was studied, the results showed that the curing coatings had excellent mechanical properties, thermal properties, glossiness, corrosion resistance and water resistance. Besides, the cureing coatings have good flexibility, adhesion force and hardness when the feeding ratio of E-51 and EPG660 was 5:1; The resin structure before and after reaction was analyzed by ATR-FT-IR.Fourthly, nano-SiO2 was added into the oligomer synthetized by E-51/EPG660 mixture after the surface of nano-SiO2 was modified by silane coupler KH570, then the novel prepolymer was cured into coatings after the photoinitiator was added. The effect of different content of nano-SiO2 on the curing efficiency, hardness and heat resistance of the coatings was studied, the results showed that the hardness and heat resistance of the coatings were excellent after the nano-SiO2 was added. The dispersion of nano-SiO2 in the novel UV-cured coatings was studied by SEM, the results showed that the dispersion of nano-SiO2 was good when the content of nano-SiO2 was less than 4wt%. |
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