Various bioengineering and industrial applications demand hard, tough, and mechanically strong polymeric blends. A novel combination of polyvinyl alcohol (PVA) and polyacrylonitrile was used to synthesize semi-IPNs using redox polymerization method in order to achieve desired property combinations in terms of toughness, generally not found in a single polymeric material. The synthesized end products in the form of polymer matrix were characterized by FTIR spectral analysis in order to confirm the incorporation of PAN into PVA, while the morphological aspects studied by AFM analysis showed fair compatibility between the component polymers exhibiting quite smooth surface and nanosize domains. Microhardness investigations were undertaken using the Vicker's indentation technique and the results were analyzed in terms of strain hardening phenomenon. Increase in surface hardness was observed as a result of variation of PVA content within the gel matrix whereas the presence of acrylonitrile as the second network was found to impart toughness as observed by the tensile strength measurements. (C) 2013 Society of Plastics Engineers