A-172/丙烯酸酯接枝改性水性环氧树脂的制备与性能

通过环氧树脂与丙烯酸、甲基丙烯酸甲酯、丙烯酸丁酯及有机硅氧烷单体乙烯基三(β-甲氧基乙氧基)硅烷(A-172)的接枝共聚反应,向环氧树脂中引入亲水性基团,使环氧树脂水性化,并在改性环氧树脂骨架中引入有机硅氧烷单元,改进环氧树脂的柔韧性和耐候性,制备具有良好水分散性和优异综合性能的有机硅氧烷接枝改性水性环氧树脂;在采用红外光谱分析接枝产物结构的基础上,采用透射电镜(TEM)、原子力显微镜(AFM)以及差示扫描量热仪(DSC)对A-172含量不同的接枝产物的水分散体及其涂膜进行了详细表征,并结合对涂膜机械性能的测试结果,分析了A-172用量对水性环氧乳液固化涂膜的微观结构及宏观性能的影响。结果表明,当A-172的质量分数为环氧树脂的6%时,改性环氧树脂乳液具有良好的分散性能和储存稳定性,其固化涂膜的耐水性、柔韧性和抗冲击强度等性能得到很大改善。

Study on synthesis and properties of A-172/acrylate grafted waterborne epoxy resins

Epoxy resin was modified with acrylic acid(AA),methyl methaerylate(MMA),butyl acrylate(BA) and an organosiloxane monomer,vinyl tris(2-methoxyethoxysilane) (A-172),by graft copolymerization.In these reactions,a hydrophilic group was introduced into the epoxy resin in order to make the modified epoxy resin soluble in water.Grafting of A-172 also improved the flexibility and weather resistance properties of the epoxy resin.The resulting waterborne epoxy resins modified with acrylates and A-172 had excellent stability and all-round properties.FT-IR spectroscopy was used to identify the structure of the grafted epoxy resin,and transmission electron microsco-PY(TEM),atomic force microscopy(AFM) and differential scanning calorimetry(DSC) were also employed to carefully characterize the emulsions and films with different amounts of A-172.Based on the results of the above tests and mechanical properties testing.the effect of varying amounts of A-172 on the properties and structure of the emulsion and the cured film was analyzed.When the amount of A-172 was 6%of the epoxy resin by mass fraction,the modified epoxy latex had excellent dispersion performance and storage stability,and the properties of the corre-sponding cured film,such as water resistance,flexibility and impact hardness,were greatly improved.