A multifunctional macromolecule poly(N-isopropylacrylamide-co-methylacrylate-co-hydrazide)(PNMH) was prepared and used to cross-link oxidized sodium alginate (OSA) to form biodegradable and thermosensitive gels.Thermo-sensitivity and degradable properties of the gels were evaluated by measuring the transmittance at different temperatures and the time dependence of the swelling ratio in phosphate buffered saline

respectively.FTIR and LCRS were applied to characterize the samples.It is showed that gels are cross-linked by the forming of CN bonds.The macromolecule PNMH shows thermo-sensitivity.With increasing PNMH content

the thermo-sensitivity of gels is improved

and degradation time of gels becomes longer.In addition

the PNMH content has great effect on the temperation dependence of swelling and degradation of hydroels.