摘要
This contribution reports an efficient approach for preparing polycarbonate block terpolymers by immortal stepwise copolymerization of CO2 with different epoxides in the presence of enol chain transfer,mediated by robust cobalt catalyst systems consisting of the fluorine substituted salen Co(Ⅲ)NO3 or biphenol-linker bimetallic Co(Ⅲ)complex in conjunction with an ionic cocatalyst,PPNX(PPN=bis(triphenylphosphine)iminium,X=NO3–or 2,4-dinitrophenoxide).Various polycarbonate block terpolymers were obtained in perfectly unimodal distribution of their molecular weights with narrow polydispersity.They all possessed only one broad glass transition temperature,which could be adjusted by altering the length of different polycarbonate segments.
This contribution reports an efficient approach for preparing polycarbonate block terpolymers by immortal stepwise copolymerization of CO2 with different epoxides in the presence of enol chain transfer, mediated by robust cobalt catalyst systems consisting of the fluorine substituted salen Co（Ⅲ）NO3 or biphenol-linker bimetallic Co（Ⅲ） complex in conjunction with an ionic cocatalyst, PPNX（PPN = bis（triphenylphosphine）iminium, X = NO3– or 2,4-dinitrophenoxide）. Various polycarbonate block terpolymers were obtained in perfectly unimodal distribution of their molecular weights with narrow polydispersity. They all possessed only one broad glass transition temperature, which could be adjusted by altering the length of different polycarbonate segments.
基金
financially supported by the National Natural Science Foundation of China (No. 21690073)
the Program for Changjiang Scholars and Innovative Research Team in University (No. IRT-17R14)
