单组分自乳化水性环氧树脂的合成及其涂膜性能研究

用有机硅、甲基丙烯酸及其酯类单体接枝改性环氧树脂,合成了具有自乳化性能的水性环氧树脂乳液。用激光粒度分析仪测定乳液的粒径及其分布,用傅里叶红外、热重分析仪对聚合产物作了结构表征和热分析。考察了温度、引发剂用量对接枝率及接枝率对乳液成膜性能的影响;甲基丙烯酸、有机硅及单体总量对乳液稳定性、成膜物耐水性和耐盐水性的影响。结果表明:当配方选用引发剂、有机硅用量分别为单体总质量的5.5%、2.5%,m(单体总量)∶m(环氧树脂)=1∶2,丙烯酸及其酯类单体的玻璃化温度Tg为30℃,体系酸值为35 mgKOH/g,接枝温度为110℃时,制得的水性环氧树脂乳液具有良好的稳定性、耐水性及耐盐水性。

Synthesis of One- Component Self- Emulsified Waterborne Epoxy Resin and Performance of Its Coating film

The self-emulsified emulsion of epoxy resin was synthesized by graft copolymerization of epoxy resin with silicone,methacrylic acid and mathacrylic ester monomer.The particle size and distribution of the emulsion were studied by Laser particle size analyzer.The structure of copolymer was characterized by FT-IR and TGA.The influence of temperature and the quantity of initiator on the grafting rate and then on the emulsion film,and the effect of methacrylic acid,silicone and the total quantity of monomers on emulsion stability,water and salt water resistance of film were investigated.The experiment data showed that when the process of grafting reaction temperature was 110 ℃,the initiator 5.5% of total monomers,the silicon 2.5%,glass transition temperature 30 ℃,acid value of resin 35 mgKOH/g,the ratio of total monomers and epoxy resin 1∶2,the waterborne epoxy resin emulsion showed good storage stability and its cured film good water and salt water resistance.Therefore,excellent performance of waterborne epoxy resin emulsion can be obtained according to the above formula and process.