为克服水性环氧丙烯酸酯脆性高的缺点，首先采用不同相对分子质量的聚乙二醇（ PEG）对环氧树脂 E51进行柔韧性改性，生成低黏度环氧树脂，将其与丙烯酸反应，得到低黏度环氧丙烯酸酯树脂，再引入丁二酸酐基团，然后用三乙胺中和成盐，加水乳化，合成了 PEG改性水性环氧丙烯酸酯（ PEG-WEA）乳液；将 PEG-WEA乳液涂覆在聚对苯二甲酸乙二醇酯（ PET）基材上。通过傅立叶变换红外光谱仪（ FT-IR）和凝胶渗透色谱仪（ GPC）表征 PEG改性环氧树脂，探究 PEG相对分子质量对 PEG-WEA乳液粒径、光固化动力学行为、光固化膜热稳定性、力学性能以及涂层性能的影响。结果表明： PEG相对分子质量为 600时，制得的 PEG-WEA乳液粒径最小（ 77. 96 nm）双键转化率得到提升，光固化膜热稳定性良好且呈现良好的韧性断裂特征，断裂伸长率提高 7. 54%，同时固化后涂层硬度达 3H，柔韧性 1 mm，附着力 2级。

In order to solve the high brittleness of epoxy acrylate，low viscosity epoxyresin was firstly prepared by flexibility modification of E51 epoxy resin using polyethyleneglycol（PEG）with different relative molecular mass. The modified resin was then used to react with acrylic acid to prepare a low-viscosity epoxy acrylate resin. Next，succinic anhydride moiety was introduced into the epoxy acrylate resin，which was then neutralized bytriethylamine into a salt and emulsified with water to obtain the PEG-modified waterborneepoxy acrylate（PEG-WEA） emulsion. Finally the prepared emulsion was coated on a polyethylene terephthalate（PET） substrate. The PEG-WEA was characterized by Fourier transform infrared spectroscopy（FT-IR）and Gel permeation chromatography（GPC）to study the effects of the relative molecular mass of PEG on the particle size of the PEG-WEAemulsion，the kinetic behavior of the UV-curing process，the thermal stability，mechanical properties and the coatings properties. The results showed that，when the relative molecular mass of PEG was 600，the PEG-WEA emulsion had the smallest particle size（77. 96 nm），the double-bond conversion rate was improved，the UV-curing film presented good thermal stability and ductile fracture characteristics，the elongation at break was increased by 7. 54%. At the same time，the hardness of the coating after curing was up to 3H，the flexibility was 1 mm，and the adhesion was 2 level.