海洋工程材料团队
[研究进展]宋其垒同学利用N-杂环卡宾与烷基硼组成的酸碱对催化剂实现了室温下双羟基聚环氧丙烷的可控合成(相关成果发表在European Polymer Journal)
发布时间: 2021-06-25 浏览次数: 58

TitleN-Heterocyclic carbene/Lewis acid-mediated ring-opening polymerization of propylene oxide. Part 2: toward dihydroxytelechelic polyethers using triethylborane


 Abstract: Propylene oxide (PO) is polymerized by metal-free ring-opening polymerization (ROP) at 25 °C using N-heterocyclic carbenes (NHCs) and triethylborane (Et3B) as a bicomponent catalytic system. Poly(propylene oxide)s with predictable molar mass up to 60 000 g.mol-1 and low dispersity (Р< 1.10) were obtained without the occurrence of undesirable transfer reaction to the monomer. In presence of an alcohol as the initiator, the ROP of PO follows an anionic mechanism assisted by monomer activation improving the efficiency of NHCs for the polymerization of substituted epoxides. Et3B is involved both in the formation of a complexed active center and in the activation of PO. Interestingly, dihydroxytelechelic PPOs can be readily synthesized not only using 1,4-benzenedimethanol but also water, both serving as difunctional initiators. Block copolyethers are also prepared by PPO chain extension experiments. All (co)polyethers have been thoroughly characterized by 1H NMR spectroscopy, SEC and MALDI-TOF mass spectrometry as means to elucidate the reaction mechanisms involved in this chemistry.

链接:https://doi.org/10.1016/j.eurpolymj.2020.109819