X-射线光电子能谱(ESCA)研究聚氯乙烯固体表面的紫外光分解反应

本文用X-射线光电子能谱(ESCA)方法探讨了聚氯乙烯(PVC)在不同环境下紫外光辐照所引起表面组成的变化。从所得结果推断:常温下PVC在大气环境中的光分解主要是光氧化反应,而在惰性气氛中主要是碳-氯键断裂释出氯化氢。由此可见,PVC的光分解反应,实际上与样品所处气氛是密切相关的。

UV-PHOTOCHEMICAL REACTION ON THE SOLID SURFACEOF POLYVINYL CHLORIDE USING X-RAY PHOTOELECTRON SPECTROSCOPY

In the present article, the changes of surface component induced by photodegradation in different environment have been examined by means of ESCA. It may be inferred from ESCA data, that the primary process in the photodegradation of PVC in atmosphere and at room temperature is the photooxdation, while in inert gas cleavage of C-Cl bond occurs accompanied with the elimination of HCl and the formation of polyene sequences of different lengths. Therefore, the photodegradation of PVC is dependent on the environment to which PVC is exposed.