St. And Mma Atom Transfer Radical Polymerization Series Initiator Lead To Efficiency And A New Complexing Agent

Transition metal catalyzed atom transfer radical polymerization(ATRP) developed by Matyjaszewski et al. and Sawamoto et al. independently in 1995 provids a new and efficient way to conduct "living"/controlled radical polymerization. By using a simple alkyl halide, RX(X=C1 and Br), as an initiator and a transition metal species complexed by suitable ligands, e.g., CuX/2,2'-bipyridine(bipy), as a catalyst, ATRP of vinyl monomers such as styrenes, (meth)acrylates and acrylonitrile proceed in a living fashion, yielding polymers with predetermined molecular weights and narrow molecular weight distributions.This dissertation includes following six parts:In the first parts, the mechanism of ATRP and the new advances in its initiating system and application in macromolecule engineering were reviewed with 102 references.In the second part, the effect of initiator structure on the polymerization rate of styrene, initiation efficiency of the initiator and molecular weight distribution of polystyrene was investigated systemically with CuX/bipy as the catalyst. It was shown that the bond dissociation energy of carbon-halide in initiator plays an important role in determining its initiation efficiency and molecular weight distribution of polystyrene. For initiators with a low bond dissociation energy, such as in the case of ethyl 2-bromoisobutate and methyl trichloroacetate, their initiation efficiencies were high and molecular weight distributions of polystyrene were narrow. While for initiators with a high bond dissociation energy, such as methyl chloroacetate, the initiation efficiency were low and the molecular weight distributions were broad. It was also found that the leaving group, X, also strongly affects the ATRP. Alkyl bromides such as benzyl bromide and ethyl 2-bromomalonate gave higher initiation efficiencies and narrower molecular weight distributions than their alkyl chloride analogues.In the third part, the effect of initiator structure on ATRP of methyl methacrylate was investigated. It was found that in the case of benzyl chloride, the initiation efficiency was very low, and that benzyl dichloride gave good control of the polymerization methyl methacrylate. However, when benzyl trichloride was used as the initiator, the polymerization rate was very...