Sequential polymerization technique has been adopted for the synthesis of a series of full and semi interpenetrating polymer network (IPN) membranes based on styrene butadiene rubber (SBR) and poly [methyl methacrylate] (PMMA). IPN morphology has been tuned by varying the blend composition and extent of cross-linking of both the phases. The dispersed and co-continuous morphologies of IPNs were characterised by AFM, SEM and TEM analysis. The transport behaviour of aromatic hydrocarbons through the membranes has been studied in detail by tracing the solvent uptake up to equilibrium. As the PMMA content in the IPN increases to 60 wt %, the solvent uptake value decreases by about 50% which is in tune with the morphological changes of the system where PMMA phase forms a well interconnected network structure with the SBR phase. The network structure has been compared with the Phantom and the Affine models and also with the theoretical predictions. (C) 2017 Elsevier Ltd. All rights reserved.