Diffusion of deuterated toluene in polystyrene

“Tunable” diffusion of D2O in CO2‐swollen poly(methyl methacrylate) films

“…Comparison of Tables 1 and 2 shows that the point at which the diffusion becomes non-Fickian corresponds to the point at which the glass transition temperature is crossed. This is similar to the effect observed by others (Gall and Kramer, 1991;Lasky et al, 1988;Mills and Kramer, 1986). These workers observed the concentration profiles during the initial stages of Case I1 diffusion.…”

Effect of solvent on nanoscale polymer heterogeneity and mobility probed by single molecule lifetime fluctuations

“…We determined the temperature dependence of N s as dN s =dT ¼ À1 segment per 9 K [7], so that a difference of three segments between the low-and high-N s plateau corresponds to a difference of 27 K in T g . The annealed film, free of solvent, has a glass transition temperature T ga ¼ 373 K. Consequently, the low-N s plateau corresponds to a system PS with trapped solvent with a glass transition temperature T gs ¼ 346 K. The plasticizing effect of solvent is often described by: kx s ¼ T ga À T gs , where x s is the solvent weight fraction and k a constant, which for the PS/toluene system is equal to 500 K [24]. For a 27 K temperature difference between T gs and T ga , a solvent weight fraction x s ¼ 5:5% is trapped in the polymer film.…”

Swelling and Transport in Polyisoprene Networks Exposed to Benzene−Cyclohexane Mixtures: A Case Study in Multicomponent Diffusion

“…Then, denoting with v 1 , v 2 , and v 3 the volume fractions of cyclohexane, benzene, and polyisoprene, respectively, in the polymer-occupied region, we find under the same assumptions used to obtain eq 3 where 12 , 13 , and 23 are three pair interaction parameters describing respectively the cyclohexanebenzene, cyclohexane-polyisoprene, and benzenepolyisoprene pair interactions. Parts a and b of eq 4 together with the relation provides a set of three coupled equations that can be solved numerically to obtain the volume fractions v 1 , v 2 , and v 3 as functions of the composition of the binary mixture (e.g., of u 1 ), of the number of monomers x between crosslinks, and of the three interaction parameters 12 , 13 , and 23 .…”