Molecular transport of aliphatic alcohols through expanded polystyrene–polyvinyl alcohol thin films

Expanded polystyrene (EPS) and polyvinyl alcohol (PVA) blend film was prepared by the non-solvent-induced phase separation method. FESEM analysis revealed the porous nature of the polymer membrane. The pore size and density were found to increase with higher loading of PVA. Mechanical testing showed that the incorporation of PVA into the EPS matrix improved Young’s modulus and tensile strength. The wettability of the film was determined by the degree of swelling (DS) and water contact angle measurements. A sharp increase in water absorption capacity and reduction in contact angle were observed for the polymer membrane with higher PVA content. Mass transport behaviour of the as-prepared film was determined using different aliphatic alcohols viz. methanol, ethanol and 2-propanol. The polymer film containing 10% PVA was taken as the optimum blend ratio since it exhibited good permeation capacity and mechanical strength. The selectivity of vapour permeation of the blend film between 2-propanol and acetone was studied.