凯芙拉分子变温中红外光谱研究

Study on temperature-dependent mid-infrared spectrum of Kevlar molecule

采用中红外(MIR)光谱开展了凯芙拉的分子结构研究,实验发现,凯芙拉分子的红外吸收模式主要包括ν(NH–凯芙拉)、ν(amide–Ⅰ–凯芙拉)、ν(amide–Ⅱ–凯芙拉)、ν(C=C–凯芙拉)、β(C—H–凯芙拉)和γ(C—H–凯芙拉)。进一步开展了凯芙拉分子的变温中红外(TD–MIR)光谱研究,结果表明,随测定温度的升高(303~573K),凯芙拉分子主要官能团对应的红外光谱波数及强度均有明显改变,凯芙拉分子热稳定性进一步降低。

The molecular structure of Kevlar was investigated by using the mid-infrared (MIR) spectrum.It is found by the experiments that the infrared absorption modes of Kevlar molecule mainly include ν(NH-Kevlar),ν(amide-Ⅰ-Kevlar),ν(amide-Ⅱ-Kevlar),ν(C=C-Kevlar),β(C—H-Kevlar) and γ(C—H-Kevlar).The study on the temperature-dependent mid-infrared (TD-MIR) spectrum of Kevlar molecule was further carried out.The results show that with the increase of the determining temperature(303~573 K),the wave number and intensity of infrared spectrum corresponding to the main functional groups of Kevlar molecule all changed significantly,and the thermal stability of Kevlar molecule further decreased.