• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>RSC Advances >Bismuth subsalicylate, a low-toxicity catalyst for the ring-opening polymerization (ROP) ofl-lactide (l-LA) with aliphatic diol initiators: synthesis, characterization, and mechanism of initiation
【24h】

Bismuth subsalicylate, a low-toxicity catalyst for the ring-opening polymerization (ROP) ofl-lactide (l-LA) with aliphatic diol initiators: synthesis, characterization, and mechanism of initiation

机译：具有脂族二醇引发剂的开环聚合（ROP）的开环聚合（ROP）的低毒性催化剂，具有脂族二醇引发剂：合成，表征和起始机理

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

The ring-opening polymerization (ROP) ofl-lactide (l-LA) was induced by the catalytic action of bismuth subsalicylate (BiSS) using linear aliphatic diols [HO(CH2)(n)OH, wheren= 2, 3, 4, 5, 6, and 8] as initiators and chain transfer agents. The theoretical and experimental degree of polymerization (DP) in all samples of alpha,omega-hydroxy telechelic poly(l-lactide) (HOPLLAOH) had a good agreement in all samples, an effect attributed to the interaction of BiSS with HO(CH2)(n)OH inducing a transfer reaction. HOPLLAOH was synthesized and characterized by a range of analytical techniques, confirming the insertion of methylene groups from the initiator into the main chain of the polyester. The glass-transition temperature (T-g) of HOPLLAOH was found to be proportional to the number of methylene groups present in the diol. Various parameters regarding the ROP ofl-LA were studied, such as temperature, time of reaction, amount of catalyst, and the nature of the diols. A kinetic study of the reaction allowed the determination of the rate constants (k) and activation energy (E-a). A mechanism of initiation is proposed based on a computational study using density functional theory (DFT), evidencing the role of the alkyl diol as an initiator, producing an alkoxide (Bi-OROH). This species then acts as a nucleophile, attacking the carbonyl group, inducing its insertion, and ultimately completing the ring-opening ofl-LA.
机译：通过使用线性脂族二醇（BISS）的催化作用，使用线性脂族二醇[HO（CH2）（n）哦，Whergen = 2,3,4， 5,6和8]作为引发剂和链转移剂。所有样品中的所有样品中的聚合（DP）的理论和实验程度（DP）在所有样品中都有良好的一致性，这一效果归因于BISS与HO（CH2）的相互作用（n）OH诱导转移反应。 HopllaoH被合成并表征了一系列分析技术，证实将亚甲基从引发剂插入聚酯的主链中。发现玻璃化转变温度（T-G）的啤酒花 - 转变温度（T-G）与二醇中存在的亚甲基数量成比例。研究了关于ROP ROP的各种参数，例如温度，反应时间，催化剂的量和二醇的性质。反应的动力学研究允许测定速率常数（K）和活化能量（E-A）。基于使用密度泛函理论（DFT）的计算研究提出了启动机制，证明烷基二醇作为引发剂的作用，产生醇盐（Bi-OOH）。然后，该物种用作亲核试剂，攻击羰基，诱导其插入，并最终完成OFL-LA的开环。

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