• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Polymers and the Environment >Influence of Short Central PEO Segment on Hydrolytic and Enzymatic Degradation of Triblock PCL Copolymers
【24h】

Influence of Short Central PEO Segment on Hydrolytic and Enzymatic Degradation of Triblock PCL Copolymers

机译：PEO中心短链段对三嵌段PCL共聚物水解和酶促降解的影响

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Hydrolytic, enzymatic degradation and composting under controlled conditions of series of triblock PCL/PEO copolymers, PCEC, with central short PEO block ( M ~(n)400 g/mol) are presented and compared with homopolymer (PCL). The PCEC copolymers, synthesized via ring-opening polymerization of ε -caprolactone, were characterized by_(1)H NMR, quantitative_(13)C NMR, GPC, DSC and WAXS. The introduction of the PEO central segment (< 2 wt%) in PCL chains significantly affected thermal degradation and crystallization behavior, while the hydrophobicity was slightly reduced as confirmed by water absorption and moisture uptake experiments. Hydrolytic degradation studies in phosphate buffer after 8 weeks indicated a small weight loss, while FTIR analysis detected changes in crystallinity indexes and GPC measurements revealed bulk degradation. Enzymatic degradation tested by cell-free extracts containing Pseudomonas aeruginosa PAO1 confirmed high enzyme activity throughout the surface causing morphological changes detected by optical microscopy and AFM analysis. The changes in roughness of polymer films revealed surface erosion mechanism of enzymatic degradation. Copolymer with the highest content of PEO segment and the lowest molecular weight showed better degradation ability compared to PCL and other copolymers. Furthermore, composting of polymer films in a model compost system at 37 °C resulted in significant degradation of the all synthesized block copolymers.
机译：介绍了在受控条件下一系列具有中心短PEO嵌段（M〜（n）400 g / mol）的三嵌段PCL / PEO共聚物PCEC的水解，酶促降解和堆肥，并将其与均聚物（PCL）进行了比较。通过ε-己内酯的开环聚合反应合成的PCEC共聚物通过（1）H NMR，定量（13）C NMR，GPC，DSC和WAXS表征。在PCL链中引入PEO中心链段（<2 wt％）显着影响了热降解和结晶行为，而疏水性则被吸水和吸水实验所证实，略有降低。 8周后在磷酸盐缓冲液中进行的水解降解研究表明重量损失很小，而FTIR分析检测到结晶度指数发生变化，而GPC测量显示出整体降解。用不含铜绿假单胞菌PAO1的无细胞提取物进行的酶降解测试证明，整个表面均具有较高的酶活性，导致通过光学显微镜和AFM分析检测到形态变化。聚合物膜粗糙度的变化揭示了酶降解的表面侵蚀机理。与PCL和其他共聚物相比，具有最高PEO链段含量和最低分子量的共聚物表现出更好的降解能力。此外，在37°C的模型堆肥系统中对聚合物薄膜进行堆肥会导致所有合成的嵌段共聚物明显降解。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号