摘要
The controllable molecular weight and polydispersity of polyacrylonitriles(PANs) were synthesized in ionic liquids(ILs) by atom transfer radical polymerization(ATRP) using ethyl-2 bromopropionate(EPN-Br) as initiator and CuBr/pentamethyldiethylenetria-mine(PMDETA) as catalyst.The polydispersity index(PDI) in the ATRP of acrylonitriel(AN) in ILs is lower than 1.3.From the polymerization kinetics,plots of ln([M]0/[M]) with time show a linear dependence at the early stage of polymerization while the deviation is observed with the conversion rate increasing.The polymerization rate in ILs,especially in 1-butyl-3-methylimidazolium chloride([bmim]Cl),is higher than that in N,N-dimethylformamide(DMF).The polymerization rate increased and the average molecular weight decreased with temperature increasing.The polymerization rate,molecular weight and PDI varied with the variation of [AN]0:[EPN-Br]0:[CuBr]0:[PMDETA]0 ratio in the experimental range,the polymerization of AN in [bmim]Cl displayed living polymerization characteristics.Moreover,the catalyst and ILs are easily isolated from the polymer and reused.
The controllable molecular weight and polydispersity of polyacrylonitriles（PANs） were synthesized in ionic liquids（ILs） by atom transfer radical polymerization（ATRP） using ethyl-2 bromopropionate（EPN-Br） as initiator and CuBr/pentamethyldiethylenetria-mine（PMDETA） as catalyst.The polydispersity index（PDI） in the ATRP of acrylonitriel（AN） in ILs is lower than 1.3.From the polymerization kinetics,plots of ln（[M]0/[M]） with time show a linear dependence at the early stage of polymerization while the deviation is observed with the conversion rate increasing.The polymerization rate in ILs,especially in 1-butyl-3-methylimidazolium chloride（[bmim]Cl）,is higher than that in N,N-dimethylformamide（DMF）.The polymerization rate increased and the average molecular weight decreased with temperature increasing.The polymerization rate,molecular weight and PDI varied with the variation of [AN]0：[EPN-Br]0：[CuBr]0：[PMDETA]0 ratio in the experimental range,the polymerization of AN in [bmim]Cl displayed living polymerization characteristics.Moreover,the catalyst and ILs are easily isolated from the polymer and reused.
基金
Shanghai Education Commission,China (No. 10ZZ44,No. 08GG11)
