Poloxamer hydrogels were prepared by photopolymerization from poloxamer macromer, which was synthesized by reaction of poloxamer 407 with acryloyl chloride. The synthesis of poloxamer macromer was confirmed using NMR and FTIR spectrometry. The gelation behavior and crystalline structure of poloxamer macromer was similar to those of poloxamer 407 itself; however, the amorphous scattering of poloxamer macromer was higher than that of poloxamer itself. Differential scanning calorimetric analysis showed that the melting temperature and enthalpy of poloxamer hydrogel were also lower than those of poloxamer itself. The compressive modulus of poloxamer hydrogels were similar (92.6-101.7 kPa), regardless of the concentration of poloxamer macromer. Equilibrium water uptake of poloxamer hydrogels decreased with an increase of concentration of poloxamer macromer. (C) 2003 Wiley Periodicals, Inc.