Search results for "Cobalt-mediated radical polymerization"

showing 4 items of 4 documents

Primary radical termination and chain transfer in vinyl polymerization

1974

Living free-radical polymerizationCobalt-mediated radical polymerizationCatalytic chain transferChemistryRadical polymerizationPolymer chemistryGeneral EngineeringLiving polymerizationChain transferReversible addition−fragmentation chain-transfer polymerizationChain terminationJournal of Polymer Science: Polymer Physics Edition
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Half-sandwich molybdenum(III) compounds containing diazadiene ligands and their use in the controlled radical polymerization of styrene

2002

Abstract The reaction of CpMoCl2 with diazadiene ligands RNCHCHNR (R2dad) affords the corresponding paramagnetic complexes CpMoCl2(R2dad) (R=Ph, 1; p-Tol, 2; C6H3Pr2i-2,6, 3; and Pri, 4). All compounds have been characterized by EPR spectroscopy and have been investigated by cyclic voltammetry. They display one-electron oxidation and reduction processes, these being reversible or irreversible depending on the nature of R. The irreversibility of the reduction wave is due to a chemical follow-up process which consists of chloride loss from the reduced product. This phenomenon is suppressed in the presence of excess chloride in solution. An X-ray structure of 3 verifies the mononuclear na…

Nitroxide mediated radical polymerizationRadical polymerization010402 general chemistryPhotochemistry01 natural sciencesBiochemistryChlorideStyreneInorganic ChemistryLiving free-radical polymerizationchemistry.chemical_compoundCyclopentadienyl complexPolymer chemistryMaterials Chemistrymedicine[CHIM.COOR]Chemical Sciences/Coordination chemistryCyclopentadienylPhysical and Theoretical ChemistryControlled radical polymerizationMolybdenumDiazadiene ligands010405 organic chemistryChemistryOrganic Chemistry[CHIM.CATA]Chemical Sciences/Catalysis0104 chemical sciences[CHIM.POLY]Chemical Sciences/PolymersCobalt-mediated radical polymerizationPolymerizationParamagnetic organometallicsmedicine.drugJournal of Organometallic Chemistry
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How the interplay of different control mechanisms affects the initiator efficiency factor in controlled radical polymerization: An investigation usin…

2007

International audience; Compound CpMoI2(iPr2dad) (iPr2dad = iPrNdouble bondCHsingle bondCHdouble bondNiPr), obtained by halide exchange from CpMoCl2(iPr2dad) and NaI, has been isolated and characterized by EPR spectroscopy, cyclic voltammetry, and X-ray crystallography. Its action as a catalyst in atom transfer radical polymerization (ATRP) and as a spin trap in organometallic radical polymerization (OMRP) of styrene and methyl acrylate (MA) monomers has been investigated and compared with that of the dichloro analogue. Compound CpMoCl2(iPr2dad) catalyzes the ATRP of styrene and MA with low efficiency factors f (as low as 0.37 for MA and ethyl 2-chloropropionate as initiator), while it irre…

Nitroxide mediated radical polymerizationRadical polymerizationAtom transfer010402 general chemistryPhotochemistry01 natural sciencesBiochemistryOne-electron oxidative additionStyreneInorganic Chemistrychemistry.chemical_compoundLiving free-radical polymerizationPolymer chemistryMaterials ChemistryReversible addition−fragmentation chain-transfer polymerization[CHIM.COOR]Chemical Sciences/Coordination chemistryPhysical and Theoretical ChemistryMethyl acrylateControlled radical polymerizationMolybdenum010405 organic chemistryChemistryAtom-transfer radical-polymerizationOrganic Chemistry[CHIM.CATA]Chemical Sciences/Catalysis0104 chemical sciences[CHIM.POLY]Chemical Sciences/PolymersCobalt-mediated radical polymerizationInitiator efficiency factor
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Polymerization of 3-alkylthiophenes with FeCl3

1992

We report on the mechanism of direct oxidation of 3-alkylthiophenes using ferric chloride (FeCl3) as the polymerization oxidant/catalyst to produce high molecular weight poly(3-alkylthiophenes) (P3ATs), conjugated polymers that have potential as electrically and optically active polymers. This study shows that the FeCl3 must exist in the solid state in the reaction mixture to be active as an oxidant in the polymerization of P3AT. A feasible polymerization mechanism for 3-alkylthiophene was developed on the basis of the crystal structure of FeCl3 and quantum chemical computations of thiophene derivatives. The polymerization is hypothesized to proceed through a radical mechanism rather than a…

Polymers and PlasticsChemistryOrganic ChemistryRadical polymerizationtechnology industry and agricultureChain transferPhotochemistryLiving free-radical polymerizationChain-growth polymerizationCobalt-mediated radical polymerizationPolymerizationPolymer chemistryMaterials ChemistryReversible addition−fragmentation chain-transfer polymerizationIonic polymerizationPolymer
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