The physical properties of poly(vinyl chloride) (PVC) and poly(N-isopropylacrylamide) [poly(NIPAAm)] blend systems, and their corresponding graft copolymers such as PVC-g-NIPAAm, were investigated in this work. The compatible range for PVC-poly(NIPAAm) blend systems is less than 15 wt % poly(NIPAAm). The water absorbencies for the grafted films increase with increase in graft percentage. The water absorbencies for the blend systems increase with increase in poly(NIPAAm) content within the compatible range for the blends, but the absorbencies decrease when the amount of poly(NIPAAm) is more than the compatible range in the blend system. The tensile strengths for the graft copolymers are larger than the corresponding blends. (C) 2000 John Wiley & Sons, Inc.