Synthesis and Biodegradation of Random and Block Copolymers of Lactide with ε-Caprolactone

• SHIRAHAMA Hiroyuki

  Department of Applied Chemistry, Faculty of Engineering, Hiroshima University

• KOJIMA Keisuke

  Department of Applied Chemistry, Faculty of Engineering, Hiroshima University

• YASUDA Hajime

  Department of Applied Chemistry, Faculty of Engineering, Hiroshima University

Bibliographic Information

Other Title

• ラクチドとε-カプロラクトンとのランダムおよびブロック共重合体の合成と生分解性
• ラクチド ト イプシロン カプロラクトン ト ノ ランダム オヨビ ブロック

Abstract

Random and block copolymers of lactide (LA; L-, DL-isomers) with ε-caprolactone (CL) and the homopolymers of these monomers were obtained in relatively high yields by making the proper changes in the polymerization conditions, using only one catalyst [AlEt₃/H₂O (1 : 0.75)].<BR>Then, the biodegradation of obtained (co) polymers by enzymes [cholesterol esterase (from Pseudomonas sp.), proteinase K (from Tritirachium album)] and activated sludge was examined. Cholesterol esterase had substrate specificity (degradability) for CL, whereas proteinase K, for LA. The former thus considerably degraded copolymers containing more CL, while proteinase K, those containing more LA. The degradability of random copolymers was generally greater than that of block copolymers.<BR>Polymer degradability was found to strongly depend not only on substrate specificity of the enzymes and primary structures of the polymers but also thermal properties such as melting point and crystallinity (heat of fusion). The L-LA/CL (=86/14) random copolymer more readily underwent degradation by proteinase K without significant change in the thermal properties of L-LA homopolymer. It was possible for the amorphous poly (DL-LA) to take on a crystalline state, though moderate enzymatic degradation continued to occur. The LA/CL copolymers could also be degraded by activated sludge.

Journal

• Journal of Japan Oil Chemists' Society

  Journal of Japan Oil Chemists' Society 47 (1), 73-81,88, 1998

  Japan Oil Chemists' Society

Keywords

• lactide
• ε-caprolactone
• random and block copolymers
• biodegradation

Details

• CRID: 1390001204091500416
• NII Article ID: 10002275042
• NII Book ID: AN10512582
• DOI: 10.5650/jos1996.47.73
• ISSN: 18841996
• ISSN: 13418327
• NDL BIB ID: 4380650
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I4380650
• Web Site: https://www.jstage.jst.go.jp/article/jos1996/47/1/47_1_73/_pdf
• Data Source:
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  • NDL
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed