| Summary: | 碩士 === 國立臺灣科技大學 === 纖維工程技術系 === 82 === Two new types of boidegradable polymer materials, copoly(L-
lactic acid/succinic anhydride/ethylene gl- ycol) and copoly(L-
lactic acid/succinic anhydride/po- lyethylene glycol),was
synthesized by means of direct copolycondensation of EG or PEG(
molar mass=200) with diacid, synthesized from L-lactic acid
and succinic anhydride,in the presence of a Ti(OBu) or SnOc
cata- lyst. The copolymers were characterized by GPC , IR , H-
NMR and contact angle.The first-order kinetics is used to
caculate the rate constants of hydrolysis reaction.The results
indicate that the lower reaction pressure,the higher molecular
weight of copolymers.T- here is no discernible difference
between the Ti(OBu) and SnOc catalysts in polymerization,as
far as mole- cular weight of products and yield of reaction
is concerned. The rate constant for more hydrophilic copoly(
LA/SA/PEG) is higher than copoly(LA/SA/EG).Ta- king into
account the rate constants of PLLA,PEG/PLLA triblock copolymers
in the previous study and copoly- mers in this study that the
rate constants of hydrol- ysis for lactic acid biodegradble
polymers is correl- ated with the ratio of no. of ester to no.
of carbon on main chain.
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