Hydroxyl-terminated polybutadiene-based (HTPB) polyurethane (PU) with different molar ratios of dimethyol propionic acid and 1,4-butane diol as the chain extender was synthesized by solution polymerization. The present PU was then cast into a membrane and subsequently characterized by the Fourier transform infrared spectroscopy. It was found that the participation of carbonyl group in hydrogen bonding increased with the content of dimethyol propionic acid in PU. The properties of the PU films including tensile strength and dynamic mechanical analysis (DMA) were studied. The tensile strength of PU films increased whereas the storage modulus decreased with increasing dimethyol propionic acid content. The glass transition temperature (T-g) Of the PU film with only 1,4-butane diol as the chain extender was 4 degreesC, while that of the films with dimethyol propionic acid as the chain extender was at about -15 degreesC. Wettability and protein adsorption on the films were evaluated from the water content, contact angle, and protein adsorptions of fibrinogen and albumin on the PU films. The diffusion coefficient of water in the membrane was determined in accordance with the Fickian diffusion mechanism. No significant difference in the diffusion coefficient was observed for all the specimens. By using the Kaelble's equation and the contact angle data, the surface tensions of the PU films with different amounts of dimethyol propionic acid were determined. The surface tension of PU film was found to increase with increasing dimethyol propionic acid content, while the opposite trend was observed for the contact angle and the amount of protein adsorption.