D,L-乳酸-肌醇星形聚合物的合成与表征

以廉价易得的D,L-乳酸和无毒的肌醇(Ins)为原料,采用工艺简单、成本低廉的直接熔融聚合法合成了肌醇聚乳酸酯——以肌醇为核的星形聚D,L-乳酸(SPDLLA)。当n(Ins)∶n(LA)=1∶120时,SPDLLA较合适的合成工艺为:140℃预聚8 h后,在w(SnCl2)=0.3%催化下,170℃熔融聚合8 h,可获得最大特性黏数[η]为1.208 dL/g的共聚物。改变投料摩尔比,合成了系列SPDLLA,并用[η]、FTIR、1HNMR、GPC、XRD等手段进行了结构与性能表征,发现不同投料比所得的SPDLLA均为无定形态,它们的Tg(35~42℃)均低于线形聚D,L-乳酸(LPDLLA),最高Mw可达8 600,可望应用于药物缓释等领域。

Synthesis and Characterization of Star-Shaped Polymer of D,L-Lactic Acid and Inositol

Using the cheap D,L-lactic acid(LA) and inositol(Ins) as starting materials,a novel polymeric ester of inositol,star-shaped poly(D,L-lactic acid)(SPDLLA),was directly synthesized via melt polycondensation.When n(Ins)∶n(LA)=1∶120,after 8 h′s prepolymerization at 140 ℃ and catalyzed by w(SnCl2)=0.3%,the product with the biggest intrinsic viscosity [η] 1.208 dL/g was obtained by melt polymerization at 170 ℃ for 8 h.The star-shaped polymer SPDLLA with different feed molar ratio were synthesized and characterized with [η],FTIR,1HNMR,GPC and XRD.All SPDLLA are amorphous,and their Tg(35～42 ℃) are lower than that of linear poly(D,L-lactic acid)(LPDLLA).The biggest Mw is 8 600,which makes SPDLLA suitable for drug delivery.