紫外光固化暗反应过程中CC双键转化率的红外光谱研究

利用红外光谱分析技术，测定了紫外光固化体系中CC双键在1 648～1 589 cm-1 特征吸收峰面积，以此研究紫外光辐照后暗反应过程中的CC双键转化率。系统地考察了光引发剂、活性稀释剂和光敏树脂等对紫外光固化暗反应的影响。研究结果表明：在45 s的紫外光辐照后，体系中40%～85%的CC双键转化是在暗反应过程中完成的，暗反应在1.75 h以后趋于平缓，但要达到95%的CC双键转化率则需要24 h以上。体系中CC双键的转化速率和最终转化率受光引发剂的种类和用量、氧阻效应以及活性稀释剂的官能度影响较大，而光敏树脂的种类及其官能度只影响转化速率，但对最终转化率影响不大。

Study on the Conversion of Acrylic C=C Double Bonds during Dark Reaction after UV Curing Using Infrared Spectroscopy

Infrared spectroscopy was used to determine 1 648-1 589 cm-1 characteristic absorption peak area so as to study the conversation of acrylic CC double bonds after UV curing. The effects of phototinitiators, active diluents and UV curing resins on the conversion of CC double bonds were also investigated. The results showed that 40%-85% of CC double bonds were conversed during dark reaction after 45 s UV curing. Dark reaction will be changed gently after 1.75 h, but 95% conversion of CC double bonds needed more than 24 h. The rates of polymerization and conversation were affected by photoinitiators, the concentration of photoinitiator, oxygen inhibition, and CC functional groups of active diluents. The rate of polymerization was affected by the CC functional groups and types of UV curing resins, but conversation was not.