Thermosensitive, transparent, and flexible semi-interpenetrating polymer networks (semi-IPNs) composed of segmented polyurethane urea/poly(N-isopropylacrylamide) (SPUU/ PNiPAAm) were new class of materials, which holds promise for its potential use as wound dressings. A series of semi-IPNs, obtained via thermal initiated polymerization of NiPAAm, were characterized by infrared spectroscopy (IR), nuclear magnetic resonance (NMR), dynamic viscoelastic measurements, wide-angle X-ray diffraction (WAXD), and mechanical properties. The resulting semi-IPNs were also investigated for their dynamic water contact angles, thermodynamic interaction parameters, in vitro drug release, and cell adhesion and detachment. The semi-IPNs with differing compositions possess good mechanical properties in both dry and hydrated states. In addition, NIH3T3 fibroblasts can attach to and detach from these semi-IPN films with varying temperature. In addition, these film extracts do not show significant cytotoxicity. Therefore, these materials have great potential for the construction of a new generation of dressings and cell transplantation for wound healing.