Pentamethyl Diethylene Triamine Complexing Agent, The St, Mma Atrp Research

In this paper, polystyrene-b-poly(styrene-co-acrylonitrile) diblock copolymer was prepared by atom transfer radical polymerization.,with CuBr/N,N,N,N",N"-pentamethyl diethene triamine as the catalyst system.Firstly,the homopolymerization of styrene and copolymerization of styrene and acrylonitrile was carried out with 1-benzyl ethane bromide(l-PEBr) as the initiator,respectively.It was proved that they are all living polymerization.lt was found that the molecular weights of the obtained polymer are proportional to monomer conversions and that the molecular weight distributions are relatively narrow.However,for the copolymerization system,the molecular weights determined by GPC are somewhat lower than that of the caculated ones,showing that the initiating efficiency of 1-PEBr is not high enough.Secondly, polystyrene-b-poly(styrene-co-acrylonitrile) diblock copolymer was synthesized by the use of polystyrene or poly(styrene-co-acrylonitrile) obtained above as the macroinitiator, respectively.lt was proved that the AB type diblock copolymer was synthesized .When poly(styrene-co-acrylonitrile) was used as macroinitiator,well-defined polystyrene-b-poly(styrene-co-acrylonitrile) diblock copolymer was prepared. However, when polystyrene was used as macroinitiator,only part of the macroinitiator initiated the block copolymer of styrene and acrylonitrile leading to the formation of diblock copolymer,which was consistent with the result of copolymerization of styrene and acrylonitrile with 1-PEBr as the initiator.Finally,the ATRP of methyl methacrylate was studied,GPC results showed the predetermined molecular weight and low polydispersity.