Journal of Polymer Science · 1952 · 14 citations · 5 references
EngineeringMaterials EngineeringMaterials ScienceMechanical Behavior Of MaterialsPolymer ChemistryRheologyMelt RheologyOscillatory RheologyPolymer CharacterizationPolymer PhysicsPolymer RheologyStress RelaxationElastic ModuliMolecular Weight DependencePolymer Chain DynamicsPolymer Conformation In MeltsPolymer Melt DynamicsPolymer Melt RheologyPolymer MeltsShear Properties Of Polymers
Abstract The elasticity of polythene melts was measured with a resonance method by inducing shear oscillations in the region about 30 cycles/second at small shear amplitudes. The experiments covered a temperature region of 130° to 230°C. and a range of (osmotic) molecular weights from 12,000–64,000. Shear moduli of the order 10 5 to 10 5 dyne cm. −2 were observed and a single relaxation time appeared sufficient to characterize the mechanical behavior of the polythene melts at a given temperature. The variation of mechanical parameters with temperature and molecular weight is brought into relation with known data on the amount of chain branching.
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