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Temperature dependence of polymer viscosity. The influence of polymer composition

1967; Wiley; Volume: 15; Issue: 1 Linguagem: Inglês

10.1002/polc.5070150133

1935-3065

Roger S. Porter, Julian F. Johnson,

Polymer Nanocomposites and Properties

Abstract The change of viscosity with temperature has been reported in the literature for a variety of linear, amorphous polymers. These data in terms of the flow activation energy, E * , indicate a wide variation among polymers with each exhibiting an essentially constant and characteristic E * at high temperature and high polymer molecular weight. These characteristic values of E * have been evaluated in terms of chemical composition and structure of individual polymer coils. The value of E * increases as a regular function of the molar volume of pendant groups along the polymer chain. More generally, a relation is shown between E * and the steric or conformational factor σ. For polyolefins, E * also increases regularly with the molar volume per monomer unit and with the mean‐square displacement length per chain unit.