Preparation of high viscosity average molecular mass poly-L-lactide
来源期刊:中南大学学报(英文版)2006年第6期
论文作者:周智华 阮建明 邹俭鹏 周忠诚 申雄军
文章页码:608 - 612
Key words:poly-L-lactidecccccc;polymerization;purification;high viscosity average molecular mass
Abstract: 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 witha viscosity average molecular mass of about 50.5×104was obtained when polymerization was conducted for 24 h at 140℃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 atypical amorphous polymeric material.The crystallinity of PLLA decreases with the increase of viscosity average molecular mass.
基金信息:the National Natural Science Foundation of China