Temperature and molecular weight dependence of mutual diffusion coefficient of cyclic polystyrene/cyclic deuterated polystyrene Bilayer films

Temperature and molecular weight dependence of diffusion behavior of cyclic polystyrenes/Cyclic Deuterated Polystyrene Bilayer Films with high purity by secondary ion mass spectroscopy (DSIMS). Monodisperse cyclic and linear polystyrenes (c-hPS, l-hPS) and those deuterated counterparts (c-dPS, l-dPS) were used in this study. Temperature dependence for c-PS and l-PS were calculated based on the empirical equations. Taking a slight difference in molecular weights of linear and cyclic molecules into account, temperature dependence value is calculated. The temperature dependence of segmental frictional coefficient for c-PS is found to be the same as that for l-PS. The effect of small amounts of linear contaminants on the diffusion of cyclic molecules might be more significant in low molecular weight regime than in high molecular weigh. The results also show that the linear contaminants can diffuse much faster than the cyclic molecules at a same annealing temperature.