TPD法对PVC热氧效应的研究

Thermal Oxidating Effect for PVC by TPD

本文采用程序升温脱附法对PVC样品进行了表面氧化性能的研究,结果表明:不同平均分子量的样品其分解温度各不相同,且均存在HC1加速脱出的动力学特征。当在不同温度下进行表面氧化后,平均分子量较低的样品其分解温度提前幅度较大。以丙酮做为探针分子在PVC表面吸附,并结合表面氧化数据,计算了不同平均分子量样品的表面双键含量。通过定量分析脉冲氧化数据,得到了PVC的表面氧化动力学参数,建立了相应的速率方程,并发现:不同PVC样品的表面氧化反应活化能与其表面双键含量及平均分子量有着密切联系。

The study of the thermal oxidating effect for PVC is made by temperature programmed desorption. It is represented that the decomposing temperatures of the PVC samples which have differnt average molecular weights are different and all the samples have the kinetic property perty of an acceleration for the escaping of HC1. There is a marked drop in the decomposing temperature of a sample which has a lower average molecular weight when the surface of the samples are oxidated. Lastly, the amount of the double bonds in surface and the kinetic parameters of the oxidating process in surface are calculated by some specific methods.