ИСТИНА

Polyvinylchloride (PVC) is among the most popular components in modern industrial composite polymer materials, whose structure can be purposefully tuned within a wide range to feature new interesting physical and chemical properties. Typical application-relevant properties of PVC-based materials are affected by the formation of conjugated double bond defects (polyene) as the result of e.g. mechanical, thermal, chemical, or optical factors. In the present contribution, the PVC structure and especially the UV irradiation-induced polyene formation in the PVC matrix are studied using a combination of several techniques, including resonance Raman spectroscopy. The latter has proven very powerful in providing structural insights in both the small crystalline and the predominantly amorphous phases in PVC. Our results uncover the size distribution and content of polyene defects in a photodegraded PVC matrix as a function of UV-irradiation doses, yielding important information relevant for PVC-based insulating materials.