Zwitterionic ring-opening polymerization of macrocyclic ethyleneoxy-substituted carbonate:Access to cyclic PEG-like polycarbonate  

作　　者：Jin Huang Jinwen Li Rui Yan Yuanyuan Qu Fengzhen Guo Lei Shen Can-liang Ma Jie Sun Zhenjiang Li Kai Guo 

机构地区：[1]State Key Laboratory of Materials-Oriented Chemical Engineering,College of Biotechnology and Pharmaceutical Engineering,Nanjing Tech University,Nanjing 211816,China [2]Institute of Nanjing Advanced Biomaterials&Processing Equipment,Lishui Economic Development Zone,Nanjing 211299,China

出　　处：《Chinese Chemical Letters》2024年第3期282-286,共5页中国化学快报（英文版）

基　　金：the China Postdoc Council(OCPC)for the financial support of Postdoctoral International Exchange Program(No.YJ20210095);the financial support from the National Natural Science Foundation of China(No.22078150);National Key R&D Program of China(No.2021YFC2101904);the Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM);the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),the Jiangsu Synergetic Innovation Center for Advanced Bio-Manufacture(No.XTB2201);the Top-Notch Academic Programs Project of Jiangsu Higher Education Institutions(TAPP)。

摘　　要：The innovation in polymer design to rival conventional polyethylene glycol(PEG)is an important approach to achieving a more sustainable society.Here,cyclic PEG-like polycarbonates having high molecular weight(4.4–49.5 kg/mol)were enabled through zwitterionic ring-opening polymerization(ZROP)of macrocyclic carbonates(MCs)mediated by N-heterocyclic carbene(NHC).The thermodynamic behavior of polymerization depends on the ring size of monomers.During this process,the ZROP of 11-membered MC was driven by the change of enthalpy(ΔH_(p))which differed from the ZROP of 14-membered MC driven by the entropic change(ΔS_(p)).Cyclic polycarbonates depicted improved thermostability(T_(d5%)≥204℃)and higher glass transition temperatures(T_(g)>–40℃)in comparison to their linear analogues(T_(d5%)≤185℃,T_(g)~–50℃).In addition,the mechanism of ZROP of MC was addressed through computational study.A distinct mechanism of polymerization distinguishable from the well-known NHC-mediated ZROP of cyclic esters was revealed,where the zwitterion from nucleophilic addition to MC,i.e.tetrahedral intermediate,cannot be ring-opened probably due to the delocalization of negative charge on the carbonate group,but serves as an active center for the polymerization.In comparison to PEG,the attained polymer demonstrated comparable hydrophilic and biocompatible properties,as revealed by the results of contact angle and in vitro cytotoxicity studies,suggesting that cyclic polycarbonate hold the promise as the alternative of PEG.

关 键 词：Zwitterionic ring-opening polymerization Cyclic polycarbonate Macrocycles Tetrahedral intermediate NHC carbene 

分 类 号：TQ323.41[化学工程—合成树脂塑料工业]