Analysis of time-dependent non-linear stress-growth data for shear and elongational flow of a low-density branched polyethylene melt

  title={Analysis of time-dependent non-linear stress-growth data for shear and elongational flow of a low-density branched polyethylene melt},
  author={Manfred H. Wagner},
  journal={Rheologica Acta},
  • M. Wagner
  • Published 1976
  • Materials Science
  • Rheologica Acta
SummaryA single integral constitutive equation is presented, which gives a reasonable description of the non-linear shear and elongational behavior of a low-density branched polyethylene melt at constant strain rate observed byMeissner. The memory function of this integral equation is a product of the memory function of Lodge's rubber like-liquid theory and a damping functionh = exp [ —n $$h = \exp [ - n\sqrt {I_2 - 3} ]$$ ], whereI2 is the second invariant of the Finger tensor. Stress- and… Expand
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