有机硅改性水性聚氨酯的合成及其光固化动力学的研究

摘要

The PUA prepolymer with isocyanate ending group has been prepared by the addition of isophorone diisocyanate (IPDI)with the mixture of polyethylene glycol (PEG600)and hydroxyl-ending polydimethylsilox-ane (PDMS).And then using dimethlolpropionic acid (DMPA)as a hydrophilic,pentaerythritol triacrylate (PETA)as an UV-curing groups and triethylamine (TEA)as a neutralizer,the waterborne polyurethane modi-fied with organosilicone (WPUA-Si)was eventually obtained through the emulsification.The structure and property of the WPUA-Si oligomer was characterized using infrared spectroscopy (FT-IR)and TG.The results show that water resistance and thermal stability of the UV-cured film of the WPUA-Si oligomer was improved. The UV-curing kinetics of the WPUA-Si oligomer was also investigated by real time FT-IR.When the amount of photoinitiator Darocur1 173 was 5wt%,UV-curing rate of the WPUA-Si oligomer was quickly and the conver-sion of the double bond was higher up to 90%.The light intensity of the radiation increasing can improve the UV-curing rate of the system.%将异佛尔酮二异氰酸酯(IPDI)加到端羟基聚二甲基硅氧烷(PDMS)和聚乙二醇(PEG600)混合物中进行反应，生成端基为异氰酸酯基的聚氨酯预聚体，用二羟甲基丙酸(DMPA)进行亲水扩链，季戊四醇三丙烯酸酯(PETA)引入光固化基团，然后用三乙胺中和，最后加水乳化，合成了一种有机硅改性水性聚氨酯乳液(WPUA-Si)。通过 FT-IR、TG、吸水率测试对其进行了研究。结果表明，有机硅改性的水性聚氨酯树脂的耐水性和热稳定性均有所提高。采用实时(real time)红外光谱原位(in situ)跟踪监测了该树脂的光固化动力学行为，结果表明，当光引发剂 Darocur1173含量为树脂质量的5％(质量分数)，体系光固化速率为最优。此外，增大辐照光强也有利于树脂的光固化。