The wettability and crystallization behaviors of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)graft-polyacrylamide (PAM) films were studied. X-ray photoelectron spectroscopy analyses illustrated that about 62 atom % of the total polar functionalities on the grafted film with 17%. grafting percentage (GP) was amide groups. Wide-angle X-ray diffraction results suggest that grafted PAM induced defects in PHBV crystals and influenced their crystal structure. Differential scanning calorimetry (DSC) spectra showed the two melting regions, 60-90 and 145-170 degrees C, of the imperfect PHBV crystals of the grafted films. Grafted PAM could suppress the recrystallization of PHBV, which was consistent with the polarizing optical microscopy results, in which the maximum PHBV spherulite diameter decreased from 350 pm for the PHBV film to 50 mu m for the film with 53% GP. In addition, DSC studies revealed that the crystallinity of the grafted films decreased with increasing GP, which facilitated the diffusion of water into the films. The water contact angle of grafted films decreased and the water-swelling percentage increased as GP went up. These results demonstrate the potential of PHBV-g-PAM for wettable surface constructs in tissue engineering applications. (C) 2007 Wiley Periodicals, Inc.