Abstract: A chain-extending UV-curable polyurethane acrylate (PUA) was synthesized with toluene diisocyanate(TDI), polyethylene glycol (PEG), hydroxyethyl acrylate (HEA),and chain extender ethylene glycol or 1,3-butanedio. The effects of PEG and chain extender on the cured film properties of the UV-cured PUA coatings were investigated. With the increase of the PEG molecular weight, the flexibility of the cured film was changed from 4.9 mm to 2 mm, and the hardness was decreased from H to 6B. The chain-extension reaction can be easily controlled between 25-30 ℃. Compared with non chain-extending UV-PUA, the dust-free time of the chain-extending UV-PUA was increased, the adhesive force was improved, and the flexibility was smaller than 1 mm. The water resistance, acid resistance, alkali resistance, heat resistance, wearing resistance and solvent resistance of the cured film were improved.

Key words: UV-curable, chain extending UV-curable polyurethane acrylate, cured film, mechanical property

摘要： 以甲苯二异氰酸酯、聚乙二醇、丙烯酸羟乙酯为反应物，并以乙二醇或 1,3－丁二醇为扩链剂，合成了扩链型聚氨酯丙烯酸酯，并以其制备了 UV 固化涂料。 研究了聚乙二醇及扩链剂对 UV 固化涂膜性能的影响。 随聚乙二醇相对分子质量的增加，涂膜的柔韧性从 49 mm 变为 20 mm，硬度从Ｈ 降低为 6B，扩链温度在 25~30 ℃之间时，扩链反应容易控制。 扩链后涂膜的表干时间变长，附着性变好，柔韧性小于 1 mm，同时涂膜耐水性、耐酸性、耐碱性、耐磨性、耐溶剂性均有所提高。

关键词: UV 固化, 扩链型聚氨酯丙烯酸酯, 固化膜, 力学性能