The effect of plasticizer o-terphenyl on the glass transition of polystyrene was investigated by Fourier transform infrared spectroscopy from a new aspect. The peak areas of four conformation insensitive bands as a function of temperature were studied, these being assigned to the vibrational modes of main chain groups and side groups of polystyrene. It was shown that the reorientation relaxation temperature of the main chain around glass transition was lower than that of the side groups when polystyrene was plasticized by o-terphenyl. It was explained on the basis of cohesional entanglements of polystyrene chains. The reorientation relaxation region of the side groups was nearly the same as the macroscopically observable glass transition region of polystyrene, implying that the glass transition process of polystyrene was dominated by the reorientation of side groups.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.