화학공학소재연구정보센터
홈 로그인 로그아웃 연락처 사이트맵
Macromolecular Research, Vol.10, No.2, 85-90, April, 2002
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Synthesis and Degradation Behaviors of PEO/PL/PEO tri-block Copolymers
Soo-Hong Lee1, 2, Soo Hyun Kim1, Young Ha Kim1, †, and Yang-Kyoo Han3
  • 1Biomaterials Research Center, Korea Institute of Science and Technology, P.O.Box 131, Cheongryang, Seoul 130-650, Korea
  • 2Department of Chemistry, Hanyang University, 17 Haengdang-dong Seongdong-gu, Seoul 133-791, Korea
  • 3Korea and Center for Advanced Functional Polymers, KAIST, Daejon 305-701, Korea
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Poly(ethylene oxide)/polylatide/poly(ethylene oxide) (PEO/PL/PEO) tri-block copolymers, which each block is connected by ester bond, were synthesized by coupling reaction of PL with PEO in the presence of pyridine. PL/PEO/PL tri-block copolymer was synthesized by ring opening polymerization of L-lactide initiated by PEO in the presence of stannous octoate. Degradation behavior of the copolymers was investigated in a pH 7.4 phosphate buffer saline (PBS) at 37±1 ℃. Gel permeation chromatography (GPC) and 1H-nuclear magnetic resonance (NMR) were used to monitor the change of mass loss, molecular weight and composition of copolymers. In hydrolytic degradation, the PEO/PL/PEO tri-block copolymer with high PEO contents affected the increase of its mass loss, and resulted in the decrease of its molecular weight as well as PEO composition. However, when PL/PEO/PL and PEO/PL/PEO tri-block copolymers had similar PEO contents, PEO/PL/PEO decreased faster in molecular weight and PEO composition than PL/PEO/PL.
Keywords:polylactide;poly(ethylene oxide);biodegradable polymer;tri-block copolymer;hydrolytic degradation
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