The mass transport properties of cyclohexane in different phase separated styrene blockcopolymer,
namely polystyrene-block-polybutadiene-block-polystyrene [SBS], polystyrene-blockpolyisoprene-
block-polystyrene [SIS] and polystyrene-block-poly(ethylene butylene)-blockpolystyrene
[SEBS] were investigated. The solubility and diffusivity in films samples have been
measured, as function of concentration, at 60\ubaC by means of sequences of differential vapor
sorption experiments run in a pressure decay apparatus. The effects of both molecular architecture
(linear and star-branched for SBS) and microstructure of the elastomer mid-segment (polybutadiene
vs poly(ethylene butylene) and polyisoprene) were considered. The sorption results were interpreted
and modeled in terms of contributions from rubbery and glassy phases. Comparison between the
different data in the binary system as function of solute concentration revealed that friction factor
for solute molecules in SEBS and SIS is significantly higher than in SBS.
Such results were also confirmed by linear viscoelastic characterization of the different
polymers that has been carried out performing small angle oscillatory shear experiments in a wide
range of temperatures between the soft block Tg and room temperature. The latter experimental
data were analyzed by Time-Temperature Superposition. The relaxation spectrum has been
determined and the monomeric friction factor has been extracted. This value has been correlated
with results from diffusion experiments leading to a substantial agreement
