Preparation of high viscosity average molecular mass poly-L-lactide
Preparation of high viscosity average molecular mass poly-L-lactide
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DOI：
10.1007/s11771-006-0001-0
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发表时间：
2006-12
影响因子：
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通讯作者：
Zhou Zhi-hua;Ruan Jian-ming;Zou Jian-peng;Z. Zhong-cheng;Shen Xiong-jun
中科院分区：
文献类型：
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作者：
Zhou Zhi-hua;Ruan Jian-ming;Zou Jian-peng;Z. Zhong-cheng;Shen Xiong-jun
以高纯L-丙交酯为原料，锡酸盐为引发剂，采用开环聚合法合成了聚L-丙交酯（PLLA），并用红外光谱、核磁共振氢谱等手段对其进行了表征。考察了引发剂浓度、聚合温度和聚合时间对聚乳酸粘均分子量的影响。研究了不同提纯方法对引发剂浓度和粘均分子量的影响。当单体与纯化引发剂的摩尔比为12 000，聚合温度为140 °C，聚合时间为24 h时，可得到粘均分子量约为50.5× 104的聚乳酸。纯化后，锡酸盐浓度降低，但不同纯化方法对PLLA粘均分子质量的影响不同，所得PLLA为典型的无定形高分子材料。PLLA的结晶度随粘均分子量的增加而降低。
Poly-L-lactide(PLLA) was synthesized by ring-opening polymerization from high purity L-lactide with tin octoate as initiator, and characterized by means of infrared, and1H-nuclear magnetic resonance. The influences of initiator concentration, polymerization temperature and polymerization time on the viscosity average molecular mass of PLLA were investigated. The effects of different purification methods on the concentration of initiator and viscosity average molecular mass were also studied. PLLA with a viscosity average molecular mass of about 50.5×104was obtained when polymerization was conducted for 24 h at 140 °C with the molar ratio of monomer to purification initator being 12 000. After purification, the concentration of tin octoate decreases; however, the effect of different purification methods on the viscosity average molecular mass of PLLA is different, and the obtained PLLA is a typical amorphous polymeric material. The crystallinity of PLLA decreases with the increase of viscosity average molecular mass.