Preparation and characterization of polylactic acid modified waxy corn starch
Polylactic acid modified waxy corn starch was prepared in the melting system of lactide using waxy corn starch as raw material and stannous iso-octoate as catalyst.A 1HNMR method for determining the substitution degree of polylactic acid modified waxy corn starch was established.The optimum process was obtained as follows:reaction time 12.46 h,reaction temperature 111.75℃,and the addition amount of lactide was 258%of starch mass.The maximum degree of substitution was predicted to be 0.0253 and adjusted by actual operation to be 0.0238.A series of characterization for polylactic acid modified starch obtained under optimal conditions proved that the particle structure was not completely destroyed,with the crystal shape and relative molecular mass better than those prepared by traditional solvent method.
NETL
NSTL
万方数据
