Lipase-mediated degradation of poly-ε-caprolactone in toluene: Behavior and its action mechanism
Lipase-catalyzed hydrolysis of poly(ɛ-caprolactone) (PCL) in toulene was investigated. PCL with number-average molecular weight (Mn) 10,000 g mol−1 was hydrolyzed using immobilized Candida antarctica lipase B (CALB). The increase in PCL concentration led to a decrease in degradation rate. Enhanced r...
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Elsevier
2016
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author | Aris, M.H. Annuar, M.S.M. Ling, T.C. |
author_facet | Aris, M.H. Annuar, M.S.M. Ling, T.C. |
author_sort | Aris, M.H. |
collection | UM |
description | Lipase-catalyzed hydrolysis of poly(ɛ-caprolactone) (PCL) in toulene was investigated. PCL with number-average molecular weight (Mn) 10,000 g mol−1 was hydrolyzed using immobilized Candida antarctica lipase B (CALB). The increase in PCL concentration led to a decrease in degradation rate. Enhanced rate was observed when reaction temperature was increased from 30 to 50 °C. Enzymatic chain scission of PCL yielded cyclic dicaprolactone, tricaprolactone, tetracaprolactone and oligomers with Mn less than ∼1000 g mol−1. Catalytic formation of cyclic lactones via back-biting mechanism in low water content environment was attributed to CALB. Its hydrolysis of PCL displayed consecutive random- and chain-end scission with time from detailed thermal, molecular weight and structural analyses. Apparent activation energy, Ea for hydrolysis was 45 kJ mol−1 i.e. half of that reverse reaction. Dicaprolactone and oligomers from hydrolysis readily re-polymerized to produce mid-range polymer with Mn 1400 g mol−1 after 36 h in the same reaction medium. |
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format | Article |
id | um.eprints-17776 |
institution | Universiti Malaya |
last_indexed | 2024-03-06T05:43:30Z |
publishDate | 2016 |
publisher | Elsevier |
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spelling | um.eprints-177762017-09-08T10:08:42Z http://eprints.um.edu.my/17776/ Lipase-mediated degradation of poly-ε-caprolactone in toluene: Behavior and its action mechanism Aris, M.H. Annuar, M.S.M. Ling, T.C. QH301 Biology Lipase-catalyzed hydrolysis of poly(ɛ-caprolactone) (PCL) in toulene was investigated. PCL with number-average molecular weight (Mn) 10,000 g mol−1 was hydrolyzed using immobilized Candida antarctica lipase B (CALB). The increase in PCL concentration led to a decrease in degradation rate. Enhanced rate was observed when reaction temperature was increased from 30 to 50 °C. Enzymatic chain scission of PCL yielded cyclic dicaprolactone, tricaprolactone, tetracaprolactone and oligomers with Mn less than ∼1000 g mol−1. Catalytic formation of cyclic lactones via back-biting mechanism in low water content environment was attributed to CALB. Its hydrolysis of PCL displayed consecutive random- and chain-end scission with time from detailed thermal, molecular weight and structural analyses. Apparent activation energy, Ea for hydrolysis was 45 kJ mol−1 i.e. half of that reverse reaction. Dicaprolactone and oligomers from hydrolysis readily re-polymerized to produce mid-range polymer with Mn 1400 g mol−1 after 36 h in the same reaction medium. Elsevier 2016 Article PeerReviewed Aris, M.H. and Annuar, M.S.M. and Ling, T.C. (2016) Lipase-mediated degradation of poly-ε-caprolactone in toluene: Behavior and its action mechanism. Polymer Degradation and Stability, 133. pp. 182-191. ISSN 0141-3910, DOI https://doi.org/10.1016/j.polymdegradstab.2016.08.015 <https://doi.org/10.1016/j.polymdegradstab.2016.08.015>. http://dx.doi.org/10.1016/j.polymdegradstab.2016.08.015 doi:10.1016/j.polymdegradstab.2016.08.015 |
spellingShingle | QH301 Biology Aris, M.H. Annuar, M.S.M. Ling, T.C. Lipase-mediated degradation of poly-ε-caprolactone in toluene: Behavior and its action mechanism |
title | Lipase-mediated degradation of poly-ε-caprolactone in toluene: Behavior and its action mechanism |
title_full | Lipase-mediated degradation of poly-ε-caprolactone in toluene: Behavior and its action mechanism |
title_fullStr | Lipase-mediated degradation of poly-ε-caprolactone in toluene: Behavior and its action mechanism |
title_full_unstemmed | Lipase-mediated degradation of poly-ε-caprolactone in toluene: Behavior and its action mechanism |
title_short | Lipase-mediated degradation of poly-ε-caprolactone in toluene: Behavior and its action mechanism |
title_sort | lipase mediated degradation of poly ε caprolactone in toluene behavior and its action mechanism |
topic | QH301 Biology |
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