Kumada chain-growth polycondensation (KCGP) is a novel method for the synthesis of well-defined conjugated polymers.Because the Ni-catalyst can transfer in an intramolecular process to the propagating chain end,the po...Kumada chain-growth polycondensation (KCGP) is a novel method for the synthesis of well-defined conjugated polymers.Because the Ni-catalyst can transfer in an intramolecular process to the propagating chain end,the polymerization follows chain-growth mechanism.With this newly developed method,various conjugated polymers,such as polythiophenes,poly(p-phenylene) (PPP),polypyrrole (PPy),and polyfluorene with controlled molecular weights and relatively narrow polydispersities (PDIs),have been prepared.Especially,the polymerizations for poly(3-alkylthiophene)s (P3ATs),PPP,and PPy exhibited quasi-living characteristics,which allows preparing polymer brushes,fully-conjugated block copolymers,and macroinitiators and macro-reactants for the synthesis of rod-coil block copolymers.In the current review,the progress in this new area is summarized.展开更多
A series of model polymerization are carried out via the one-pot externally initiated Kumada catalyst-transfer polycondensation （KCTP） of 2-bromo-5-chloromagne- slum thiophene monomers, and the excess amount of init...A series of model polymerization are carried out via the one-pot externally initiated Kumada catalyst-transfer polycondensation （KCTP） of 2-bromo-5-chloromagne- slum thiophene monomers, and the excess amount of initiators or catalysts are found no need to be isolated during the polycondensation process. Especially, the impacts of the nickel catalyst loading variation on regioregularity （rr）, yield, molecular weight （Mn）, polydispersity （PDI） and initiation efficiency of poly（3-hexylthiophene） （P3HT） are systematically investigated. The IH NMR, size-exclusion chromatography （SEC）, and MALDI-TOF mass spectroscopy results indicated that an excess amount of catalyst does not influence yield, rr, Mn, and PDI of P3HT, nor the initiation efficiency. However, the PDI of the product is broad, and the Mn and rr values decreased in the absence of 1,3-bis （diphenylphosphino）propane （dppp）. It can be concluded that the in-situ KCTP polymerization of P3HT is a practical and effective process. These results are especially valuable for the synthesis of all-conjugated block copolymers where macroinitiators are used.展开更多
基金supported by the National Natural Science Foundation of China (20921061,20923003 & 50833004)the National Basic Research Program of China (2009CB930603)
文摘Kumada chain-growth polycondensation (KCGP) is a novel method for the synthesis of well-defined conjugated polymers.Because the Ni-catalyst can transfer in an intramolecular process to the propagating chain end,the polymerization follows chain-growth mechanism.With this newly developed method,various conjugated polymers,such as polythiophenes,poly(p-phenylene) (PPP),polypyrrole (PPy),and polyfluorene with controlled molecular weights and relatively narrow polydispersities (PDIs),have been prepared.Especially,the polymerizations for poly(3-alkylthiophene)s (P3ATs),PPP,and PPy exhibited quasi-living characteristics,which allows preparing polymer brushes,fully-conjugated block copolymers,and macroinitiators and macro-reactants for the synthesis of rod-coil block copolymers.In the current review,the progress in this new area is summarized.
文摘A series of model polymerization are carried out via the one-pot externally initiated Kumada catalyst-transfer polycondensation （KCTP） of 2-bromo-5-chloromagne- slum thiophene monomers, and the excess amount of initiators or catalysts are found no need to be isolated during the polycondensation process. Especially, the impacts of the nickel catalyst loading variation on regioregularity （rr）, yield, molecular weight （Mn）, polydispersity （PDI） and initiation efficiency of poly（3-hexylthiophene） （P3HT） are systematically investigated. The IH NMR, size-exclusion chromatography （SEC）, and MALDI-TOF mass spectroscopy results indicated that an excess amount of catalyst does not influence yield, rr, Mn, and PDI of P3HT, nor the initiation efficiency. However, the PDI of the product is broad, and the Mn and rr values decreased in the absence of 1,3-bis （diphenylphosphino）propane （dppp）. It can be concluded that the in-situ KCTP polymerization of P3HT is a practical and effective process. These results are especially valuable for the synthesis of all-conjugated block copolymers where macroinitiators are used.
