摘要
Porcine pancreas lipase(PPL) immobilized on narrow distributed micron glass beads was employed successfully for ring-opening polymerization of ε-caprolactone(CL).Different polymerization conditions such as enzyme concentration,reaction temperature and reaction time were studied.The results showed that M_n of the resulting PCL was significantly increased compared with that catalyzed by PPL.Higher temperature and longer reaction time both contributed to gaining PCL with a higher molecular weight,while the yield had almost no change.In addition,for evaluating the recyclibilty of immobilized PPL on narrow distributed micron glass beads for the ring-opening polymerization of CL,we adopted the most severe reaction conditions(180 ℃,(240 h)) in the recycling experiments.It was found that the recovered immobilized PPL could be used again with a compatible high catalytic activity.The highest M_n of 21 300 of PCL could be obtained at a mass fraction of 5.18% of the reused immobilized PPL at 180 ℃ for 240 h,which is the highest M_n of PCL catalyzed by PPL.The excellent recyclability of immobilized PPL on narrow distributed micron glass beads is very helpful to its further industry applications.
Porcine pancreas lipase (PPL) immobilized on narrow distributed micron glass beads was employed successfully for ring-opening polymerization of ε-caprolactone (CL). Different polymerization conditions such as enzyme concentration, reaction temperature and reaction time were studied. The results showed that Mn of the resulting PCL was significantly increased compared with that catalyzed by PPL. Higher temperature and longer reaction time both contributed to gaining PCL with a higher molecular weight, while the yield had almost no change. In addition, for evaluating the recyclibihy of immobilized PPL on narrow distributed micron glass beads for the ring-opening polymerization of CL, we adopted the most severe reaction conditions ( 180 ℃, 240 h) in the recycling experiments. It was found that the recovered immobilized PPL could be used again a compatible high catalytic activity. The highest Mn of 21 300 of PCL could be obtained at a mass fraction of 5.18% of the reused immobilized PPL at 180℃ for 240 h, which is the highest Mn of PCL catalyzed by PPL. The excellent recyclability of immobilized PPL on narrow distributed micron glass beads is very helpful to its further industry applications.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2006年第5期982-984,共3页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:20104005)资助
关键词
猪胰脂肪酶
固定化
微米硅球
酶促开环聚合
聚Ε-己内酯
Porcine pancreas lipase
Immobilization
Micron glass beads
Enzymatic ring-opening polymerization
Poly (ε-caprolactone)