Surface characterization of photodegraded dyed styrene butadiene and natural rubbers

Abstract

AbstractThe combination of laser ablation coupled to mass spectrometry, Ultraviolet‐visible spectroscopy and environmental scanning electron microscopy (coupled with energy dispersive X‐ray spectrometry EDX) as independent techniques to investigate the surface photooxidation of dyed filled natural rubber (NR) and styrene butadiene rubber (SBR), designed for outdoor applications, have been investigated. The aging results in the deterioration of the exposed surface material properties. Results indicate that dyed filled NR and SBR samples behave differently during the photooxidation. The fading of the dyed polymers was found to be promoted in the NR sample. This is proved by the disappearance of [M − H]− pseudomolecular ion of orange pigment and also its fragment ions after aging, which was detected by LDI–FTICRMS. This is confirmed by both EDX and UV/vis spectroscopy. EDX analysis indicates a concentration of chlorine atoms, which is a marker of orange pigment or of its degradation products, at the surface of SBR flooring after aging, which is not observed with NR. Reactivity of the radicals formed during flooring aging is thought to greatly affect the behavior of the organic pigment and is discussed. Copyright © 2008 John Wiley & Sons, Ltd.