Applied Organometallic Chemistry · 2006 · 22 citations · 29 references
Natural SciencesChemical EngineeringChemistryCatalysisOrganic ChemistryPolymer ChemistryPolymer CharacterizationPolymer Physical ChemistryPolymer StructurePolymer SynthesisPolymerization ChemistryPolymerization ProcessesCoordination PolymerizationCopolymerizationCopolymerization BehaviorCopper ChemistryMolecular Structure DeterminationPolymerization Mechanism AnalysisPolymerization ReactionsRandom Copolymers
Abstract Vinyl‐type polymerization of norbornene as well as random copolymerization of norbornene with styrene was studied using a series of copper complexes‐MAO. The precatalysts used here are copper complexes with β‐ketoamine ligands based on pyrazolone derivatives and the molecular structure of complex 4 was determined using X‐ray analysis. All of these catalyst systems are moderately active for the vinyl‐type polymerization of norbornene and random copolymerization of norbornene with styrene. The random copolymers obtained suggest that only one type of active species is present. Gel permeation chromatography (GPC) and NMR indicate that the copolymers are ‘true’ copolymers. The copolymerization reactivity ratios ( r NBE = 20.11 and r Sty = 0.035) indicate a much higher reactivity of norbornene, which suggests a coordination polymerization mechanism. The solubility and processability of the copolymers are improved relative to polynorbornene and the thermostability of the copolymers is improved relative to polystyrene. Copyright © 2006 John Wiley & Sons, Ltd.
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