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.