Abstract:
Polypropylene glycol diglycidyl ether-
co-citric acid copolyester(PPGDECA) and polypropylene glycol-
co-citric acid copolyester(PPGCA) were synthesized by the reaction of citric acid with polypropylene glycol diglycidyl ether and polypropylene glycol,respectively.Their structures were characterized.Their blends with polylactide(PLA) were prepared via melt blending.Experimental results showed that PPGDECA was well dispersed in PLA matrix when the mass fraction of PPGDECA was under 10%,while PPGDECA become badly dispersed with reduced mechanical properties when the mass fraction of PPGDECA was above 10%.Comparison of two copolymers showed that PPGDECA had higher plasticizing efficiency whose blends showed higher tensile strength,higher tensile modulus,lower migration rate,and better comprehensive performance than PPGCA.