THEORETICAL INVESTIGATIONS OF THE STABILITY OF DEGRADATION PRODUCTS OF POLYSTYRENE AND POLY(4-VINYLPYRIDINE)

The products of thermal degradation of polystyrene and poly(4-vinylpyr idine) have been rationalized using ASED-MO theory. The calculations e xplain the formation of styrene dimer and the absence of 4-vinylpyridi ne dimer during the thermal degradation, which may be due to the high reactivity of 4-vinylpyridine dimer. According to frontier molecular o rbital (FMO) treatment, the reactivity of the molecule is controlled b y the energy separation between HOMO and LUMO. It was found that 4-vin ylpyridine dimer is more reactive than styrene dimer due to its smalle r energy separation.