The homopolymer brushes of polyacrylamide(PAAM) on spherical silicon gel were synthesized by atom transfer radical polymerization(ATRP). The silicon gel initiator was prepared by self-assemble. Utilizing these modifie...The homopolymer brushes of polyacrylamide(PAAM) on spherical silicon gel were synthesized by atom transfer radical polymerization(ATRP). The silicon gel initiator was prepared by self-assemble. Utilizing these modified silicon gel as the substrate, a kind of novel inorganic-organic hybrid material with the polymer metal complex was synthesized. The result of ESR indicates that the inorganic/organic hybrid material with the polymer metal complex based on silicon gel possesses well paramagnetis.展开更多
The atom transfer radical polymerization of styrene was carried out with an α-haloketone, 2-bromocyclohexanone, as the initiator in the presence of CuBr/Cu/2,2′-bipyridine or CuBr/ N,N,N′,N″,N″-pentamethyldiethyl...The atom transfer radical polymerization of styrene was carried out with an α-haloketone, 2-bromocyclohexanone, as the initiator in the presence of CuBr/Cu/2,2′-bipyridine or CuBr/ N,N,N′,N″,N″-pentamethyldiethylenetriamine catalytic system. The polymerization proceeded in a living fashion with that the number average molecular weight increased linearly with the increase of monomer conversion and the polydispersity was relatively low through the polymerization process, especially with CuBr/N,N,N′,N″,N″-pentamethyldiethylenetriamine as the catalyst. The initiation efficiency of 2-bromocyclohexanone in both catalysis systems was about 80%. 1H NMR and 13C NMR verified the presence of 2-oxocyclohexyl and bromine atom at the both ends of polystyrene chains respectively, which were derived from the 2-bromocyclohexanone.展开更多
A novel hydroxy-capped comb-like block polymer, poly[poly(ethylene glycol)](HCPEG), was prepared via atom transfer radical polymerization(ATRP) of α-methylacryloyl-ω-hydroxyl-poly(ethylene glycol). The polymerizatio...A novel hydroxy-capped comb-like block polymer, poly[poly(ethylene glycol)](HCPEG), was prepared via atom transfer radical polymerization(ATRP) of α-methylacryloyl-ω-hydroxyl-poly(ethylene glycol). The polymerization kinetics of the PHPEGMA was studied by gel permeation chromatography and 1H NMR. The semilogarithmic plot of monomer conversion vs. reaction time increases linearly before the conversion is up to more than 70% and the number-average molecular weights(M_n) by GPC increased linearly with increase of the monomer conversion up to 100%, while the polydispersity index remained fairly narrow with M_w/M_n<1.2.展开更多
文摘The homopolymer brushes of polyacrylamide(PAAM) on spherical silicon gel were synthesized by atom transfer radical polymerization(ATRP). The silicon gel initiator was prepared by self-assemble. Utilizing these modified silicon gel as the substrate, a kind of novel inorganic-organic hybrid material with the polymer metal complex was synthesized. The result of ESR indicates that the inorganic/organic hybrid material with the polymer metal complex based on silicon gel possesses well paramagnetis.
文摘The atom transfer radical polymerization of styrene was carried out with an α-haloketone, 2-bromocyclohexanone, as the initiator in the presence of CuBr/Cu/2,2′-bipyridine or CuBr/ N,N,N′,N″,N″-pentamethyldiethylenetriamine catalytic system. The polymerization proceeded in a living fashion with that the number average molecular weight increased linearly with the increase of monomer conversion and the polydispersity was relatively low through the polymerization process, especially with CuBr/N,N,N′,N″,N″-pentamethyldiethylenetriamine as the catalyst. The initiation efficiency of 2-bromocyclohexanone in both catalysis systems was about 80%. 1H NMR and 13C NMR verified the presence of 2-oxocyclohexyl and bromine atom at the both ends of polystyrene chains respectively, which were derived from the 2-bromocyclohexanone.
文摘A novel hydroxy-capped comb-like block polymer, poly[poly(ethylene glycol)](HCPEG), was prepared via atom transfer radical polymerization(ATRP) of α-methylacryloyl-ω-hydroxyl-poly(ethylene glycol). The polymerization kinetics of the PHPEGMA was studied by gel permeation chromatography and 1H NMR. The semilogarithmic plot of monomer conversion vs. reaction time increases linearly before the conversion is up to more than 70% and the number-average molecular weights(M_n) by GPC increased linearly with increase of the monomer conversion up to 100%, while the polydispersity index remained fairly narrow with M_w/M_n<1.2.