Journal of Polymer Science · 1959 · 45 citations · 4 references
Natural SciencesChemistryMaterials SciencePhysical ChemistryPolymer ChemistryPolymer MaterialsIonic PolymersPolymer Physical ChemistryPolymer StructurePolymer SynthesisPolymerization ChemistryPolymerization ProcessesAnionic PolymerizationBlock CopolymerizationCopolymer Composition AnalysisCopolymerizationCopolymerization StrategiesPolymer Copolymer Composition AnalysisRadical Propagation MechanismsSodium Dispersion
Abstract Data are presented for copolymer composition as a function of monomer composition in the system styrene‐methyl methacrylate initiated by lithium in tetrahydrofuran and hydrocarbons. The data are interpreted in the light of the electron exchange initiation and ion‐radical propagation mechanisms previously proposed. Revised r 1 and r 2 values for strictly anionic copolymerization of styrene and methyl methacrylate are presented on the basis of data obtained with the use of n ‐butyllithium and phenylsodium as typical anionic initiators in hydrocarbons. Sodium dissolved in liquid ammonia and sodium dispersion in hydrocarbons gave results identical with those obtained with true anionic catalysts. This is in sharp distinction to the results obtained with lithium.
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