| Abstract: | Polyurethanes based on PPG 2000 with variable concentrations of TDI and TMP were prepared and used for sorption studies, employing homologous series of hydrocarbons such as benzene, toluene and xylene. The sorption was observed to be non-Fickian in nature. The solubility parameter of the polyurethane series was observed to be 9·7(calcm-3)1/2. The polymer solvent interaction parameter χ was found to be lowest in benzene, suggesting higher interaction with it. The sorption and diffusion coefficients were observed to increase with a decrease in the degree of crosslinking. Molecular weights between crosslinks were calculated using the Flory–Rehner equation and compared with those obtained theoretically. © 1998 Society of Chemical Industry |
