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采用原位红外光谱法研究了PTPEG/GAP反应动力学.利用PTPEG/GAP反应体系在2100 cm-1和1086 cm-1吸光度比值与反应时间的关系得到了PTPEG/GAP本体末端点击化学交联反应的动力学曲线.曲线拟合表明,PTPEG/GAP本体末端交联反应过程分为明显的两个阶段;30℃时第一阶段反应动力学结束于535 min,40℃时为305 min,50℃时为295 min,60℃时为115 min.黏度测试表明,PTPEG/GAP反应体系黏度(η)随时间(t)变化曲线呈“L”型;30℃时η-t曲线拐点出现于540 min,40℃时为320 min,50℃时为305min,60℃时为118 min,拐点前后分别对应PTPEG/GAP凝胶前、凝胶后状态;且η-t曲线拐点时间与PTPEG/GAP第一阶段反应动力学结束时间相吻合.Arrhenius公式拟合表明,凝胶前,PTPEG/GAP末端点击化学交联反应表观活化能Ea1为(45.57±2.77)k J/mol;凝胶后,表观活化能Ea2为(59.50±4.01)k J/mol.
The kinetics of PTPEG / GAP reaction was studied by in situ FTIR spectroscopy. The relationship between the absorbance ratio of 2100 cm-1 and 1086 cm-1 at PTPEG / GAP and the reaction time was obtained. The curve fitting showed that there were two distinct phases in the end-crosslinking reaction of PTPEG / GAP. At the end of 30 ℃, the kinetics of the reaction in the first phase reached 535 min and reached 305 min at 40 ℃ Was 295 min at 60 ℃ and 115 min at 60 ℃ .The viscosity curve showed that the curve of viscosity (η) over time (t) was “L” in PTPEG / GAP reaction system. 540 min, 320 min at 40 ℃, 305 min at 50 ℃, and 118 min at 60 ℃, respectively. Before and after the inflection point, the state of PTPEG / GAP gel was observed before and after gelation. The inflection time of η-t curve was similar to that of PTPEG / GAP The Arrhenius formula fitting showed that the apparent activation energy Ea1 of the chemical cross-linking reaction at the end of PTPEG / GAP was (45.57 ± 2.77) kJ / mol before gel, The apparent activation energy Ea2 was (59.50 ± 4.01) kJ / mol.