An XPS Investigation of Thermal degradation and Charring of Cross-linked Polyisoprene and Polychloroprene
Polymer Degradation and Stability
Our interest in butadiene-containing polymers had led to an investigation of the thermal degradation of polyisoprene, PIP, and polychloroprene, PCP. The connection between cross-linking and thermal stability through an examination of PIP and PCP has been reported. Like the course of thermogravimetric analysis (TGA) the cross-linking and charring of polymers subjected to heat can also be experimentally observed as function of temperatures by the pseudo-in-situ XPS (X-ray Photoelectron Spectroscopy). Data acquisition of C1s spectra as function of temperature permits us to explore: (1) the extent of cross-linking and/or carbon accumulation of systems of PCP and PIP with/without initiators, BPO and DCP, via the analysis of the relative intensity versus temperature; and (2) the onset of charring by determining the limiting transition temperature (LTGRL) of the graphite-like structure and particularly the plasmon loss (ΔEL).