Membranes with high strength and elasticity are of great demand in patch therapy. Similar membranes have been developed by combining carboxy- functionalized multiwalled carbon nanotube (c-MWCNT) with different poly(vinyl alcohol) (PVA) as potential diltiazem delivery device through aqueous mixing. High molecular weight PVA (PVAH) produced stronger interaction with c-MWCNT than low molecular weight PVA (PVAL) preferably at low concentration. Positive changes in favor of PVAH in infrared and solid state 13C nuclear magnetic resonance spectroscopy, wide angle X-ray scattering, thermal stability, morphology and dry and wet mechanical properties clearly demonstrate that. Fibrillar c-MWCNT array at 1 wt.% in PVAH (PVAH/1) has drastically improved PVA crystalline cell dimension, tensile strength (201%) and elongation (196%) than neat PVA H whereas the similar improvement is much less (100% and 185%) in PVAL (PVAL/1) due to globular morphology. Instead, c-MWCNT performed better at 0.5 wt.% in PVAL (PVAL/0.5). The kinetic data reflects better encapsulation and slower release by PVAH (5.87%) than PVAL (10.17%) due to greater interfacial interaction. © 2012 Elsevier Ltd. All rights reserved.