扩链型UV固化聚氨酯丙烯酸酯的合成及性能研究

Synthesis and Properties of Chain-Extending UV-Curable Polyurethane Acrylate

以甲苯二异氰酸酯、聚L--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4．9mm变为2．0mm，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1mm，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。

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 con- trolled 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 flexibi- lity 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.