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首页> 外文期刊>RSC Advances >Ring opening polymerization of epsilon-caprolactone in the presence of wet beta-cyclodextrin: effect of the operative pressure and of water molecules in the beta-cyclodextrin cavity
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Ring opening polymerization of epsilon-caprolactone in the presence of wet beta-cyclodextrin: effect of the operative pressure and of water molecules in the beta-cyclodextrin cavity

机译：湿β-环糊精存在下ε-己内酮的环开口聚合：β-环糊精腔中的操作压力和水分子的效果

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摘要

The ring opening polymerization (ROP) of epsilon-caprolactone (CL) in the presence of beta-cyclodextrin (beta-CD) was performed in batch reactors both at room pressure and with the reaction system pressurized with CO2, N-2 or Ar. Significant enhancements of the polymerization rate was observed when the ROP was carried out with wet beta-CD under pressure. For example, after 24 hours at 120 degrees C with a beta-CD/CL molar ratio of about 1/100, the monomer conversion increased from 4 to 98-99% when the pressure was changed from 0.1 to 12.5-13.0 MPa independent of the nature of the compressing gas. MALDI-TOF analyses indicated that a major fraction of polymer chains obtained in pressurized systems was initiated by water molecules. The collected results suggest that at 12-13 MPa wet beta-CD can catalyse both the ring opening of epsilon-caprolactone and the polymerization of the obtained linear species and that high energy water molecules located inside the cavity of the cyclic oligosaccharide must play a role in initiating the polymerization. The trend of number average molecular weight and the results of MALDI-TOF analyses obtained in polymerizations performed for long reaction times and in a hydrolysis test of commercial poly(epsilon-caprolactone) indicate that wet beta-CD can work as an artificial lipase enzyme under the adopted conditions.
机译：在室温下，在β-环糊精（Beta-CD）存在下，在β-环糊精（Beta-CD）存在下，在空间反应器和用CO 2，N-2或Ar加压的反应体系中，在β-环糊精（Beta-CD）中进行ε-环糊精（β-CD）的开环聚合（ROP）。当在压力下用湿β-Cd进行ROP时，观察到聚合速率的显着增强。例如，在120摄氏度下24小时后，β-CD / Cl摩尔比为约1/100，当压力从0.1〜12.5-13.0MPa改变时，单体转化从4〜98-99％增加到0.5至12.5-13.0MPa压缩气体的性质。 MALDI-TOF分析表明，通过水分子引发加压系统中获得的聚合物链的主要部分。收集的结果表明，在12-13MPa湿β-CD中可以催化ε-己内酯的环开口和所获得的线性物质的聚合，并且位于环状寡糖的腔内的高能量水分子必须发挥作用在开始聚合时。数均分子量的趋势和在商业聚（ε-己内酯）的长反应时间和水解试验中进行的聚合中获得的MALDI-TOF分析结果表明湿β-CD可以作为人工脂肪酶通过的条件。

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  • 来源
    《RSC Advances》 |2016年第93期|共10页
  • 作者

    Galia Alessandro; Scialdone Onofrio; Spano Tiziana; Valenti Maria Grazia; Grignard Bruno; Lecomte Philippe; Monflier Eric; Tilloy Sebastien; Rousseau Cyril;

  • 作者单位

    Univ Palermo Dipartimento Ingn Chim Gest Informat Meccan Viale Sci Ed 6 I-90128 Palermo Italy;

    Univ Palermo Dipartimento Ingn Chim Gest Informat Meccan Viale Sci Ed 6 I-90128 Palermo Italy;

    Univ Palermo Dipartimento Ingn Chim Gest Informat Meccan Viale Sci Ed 6 I-90128 Palermo Italy;

    Univ Palermo Dipartimento Ingn Chim Gest Informat Meccan Viale Sci Ed 6 I-90128 Palermo Italy;

    Univ Palermo Dipartimento Ingn Chim Gest Informat Meccan Viale Sci Ed 6 I-90128 Palermo Italy;

    Univ Liege Ctr Educ &

    Res Macromol B6a Sart Tilman B-4000 Liege Belgium;

    Univ Lille Univ Artois CNRS Cent Lille ENSCL Unite Catalyse &

    Chim Solide UMR F-62300 Lens France;

    Univ Lille Univ Artois CNRS Cent Lille ENSCL Unite Catalyse &

    Chim Solide UMR F-62300 Lens France;

    Univ Lille Univ Artois CNRS Cent Lille ENSCL Unite Catalyse &

    Chim Solide UMR F-62300 Lens France;

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  • 正文语种 eng
  • 中图分类 化学;
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