The Heats of Combustion of Polythene and Polyisobutylene

Abstract
Values, with uncertainties of about 0.03 percent, are here presented for the heats of combustion of polythene and polyisobutylene. The results for polythene indicate that this polymer is crystalline at least to the extent of about 50 percent at 25°C. The results for polyisobutylene are abnormally high and can be explained on the basis of a steric interference effect within the molecules of this liquid polymer.