A novel grafting copolymer was synthesized by reacting DL-lactide with corn starch in N

N-dimethylacetamide(Me2NAC) in the presence of triethylamine(NEt3) and anhydrous lithium chloride．The effect of reaction time and the molar ratio of DL-lactide to structural unit of starch on monomer conversion (C％)

grafting(G％)and grafting efficiency(GE％)has been studied The C％

G％and GE％couldapproach 37.3％．179.7％and 68.0％。respectively when the molar ratio of DL-lactide to structural unit of starch is 10：1．the grafting copolymerization was carried out at 80～85℃ for 4h in a nitrogen atmosphere．Several techniques such as Fourier transform infrared(FTIR) spectroscopy

differential scanning calorimetry(DSC) and X-ray diffraction (XRD) were used to characterize the grafting copolymer．FTIR spectrumshows an absorption band at 1740cm-1 confirming the formation of ester bond

indicating the starch／DL-lactide grafting copolymer was produced．The DSC characteristic result showed the melting temperature of the grafting copolymer elevated slightly as the molar ratio of DL-lactide to glucose structural units of starchincreased and the X-ray diffraction pattern showed the synthesized grafting copolymer was an amorphouscopolymer．The degradability of grafting copolymer was tested with the aid of acid

alkali and microbe The weight loss of the grafting copolymer was 100％ after 70h in0.5mol／L hydrochloric acid solution at 30℃． but the weight loss of the grafting copolymer approaching to 100％after 35h in 0．2mol／L sodium hydroxide solution at 30℃．the weight loss of the glucose structural unit of starch and DL-polylactide chain in the grafting copolymer was 41.8％ and 24.0％ after 20 days and 30 days of incubation with bacillus subtilis and staphylococcus aureus at 37℃ respectively The grafting copolymer produced can be used as a component in hot-melt adhesives and as an impermeable coating for paper and cardboard．