Synthesis of Temperature- and pH-Sensitive Graft Copolymer Containing 2-(Diethylamino)ethyl Methacrylate and N-Vinylcaprolactam onto Silicone Rubber

Silicone rubber films were modified by the consecutive grafting of 2-(diethylamino)ethyl methacrylate (DEAEMA) and N-vinylcaprolactam (NVCL) using direct method on two steps with gamma-rays. The effect of absorbed dose and monomer concentration on grafting degree was determined. The grafted samples were verified by FTIR-ATR spectroscopy and swelling;thermal properties were analyzed by DSC and TGA. The stimuli-responsive behavior was studied by swelling and/or DSC. Thermo- and pH-sensitive films of (PP-g-DEAEMA)-g-NVCL presented a pH critical at 3.2 and LCST around 63.5℃.

酸掺杂聚苯胺催化2-(二乙氨基)乙基己酸酯及反应动力学

以正己酸和二乙氨基乙醇为原料,对甲苯磺酸掺杂聚苯胺为催化剂催化合成2-(二乙氨基)乙基己酸酯,考察反应过程的影响因素,并测定反应动力学数据。表明适宜的合成工艺条件为n(二乙氨基乙醇)∶n(正己酸)为1∶2,催化剂用量为醇酸总质量的2%,带水剂用量为醇酸总质量的120%,反应时间为3.2h。此时,二乙氨基乙醇转化率可达96.8%,催化剂重复使用4次后,二乙氨基乙醇的转化率为84.4%。采用还原后的催化剂进行的实验二乙氨基乙醇转化率可达95.2%。表观活化能为74.256kJ/mol,指前因子为2.70×107 L/(mol·min)。对甲苯磺酸掺杂聚苯胺具有很好的催化活性。该酯化反应对正己酸和二乙氨基乙醇均为一级反应。