EA/MMT纳米复合材料的制备及其光固化动力学研究

通过4 - 溴甲基二苯甲酮与二甲基正十八胺反应合成的季铵盐光引发剂苯甲酰苄基二甲氨基十八烷基溴化铵(BDOB),进行插层修饰蒙脱土(MMT),通过层间引发聚合法光固化制备环氧丙烯酸酯/蒙脱土(EA/MMT)纳米复合材料;利用红外光谱法对EA/MMT的光固化行为进行了研究.XRD和TEM分析结果表明,MMT在光固化复合材料中已得到插层和部分剥离;增加光引发剂浓度及提高环境温度均可提高其固化速率和双键最终转化率,氧气的存在使体系的诱导期延长,双键转化率降低;光固化反应总级数约为6～7,表观活化能为9.8 kJ/mol.

Preparation and UV Curing Kinetics of EA/MMT Nanocomposites

EA/MMT UV-cured nanocomposites were prepared by using modified clays and epoxy resin via intra-gallery UV-curing polymerization, and the organic modified clays were used as the only photoinitiator. The organic modified clays were modified with new potoinitiator benzoylbenzyl-N,N-dimethyl-N-octadecylammonium bromide quaternary ammonium salt, which was synthesized through the reaction of 4-bromomethyl benzophenone with octadecyl dimethyl amine. The UV-cured process kinetics of the EA/MMT nanocomposites were studied immediately after UV exposure by means of infared spectroscopy. The morphology of the EA/MMT nanocomposites was studied using XRD and TEM, and the results showed that all the samples had an intercalated structure with partial exfoliation. It was found that both curing rate (R) and ultimate vinyl conversion (C) could be raised by increasing photoinitiator concentration and elevating temperature. The oxygen possessed an inhibition effect that prolonged the induction period on the curing. And the total apparent reaction exponent and apparent activation energy were obtained within the range of 6～7 and 9.8 kJ/mol.