Dimensional Changes in Ultradrawn Polyethylene.

Abstract

Samples of ultradrawn high density polyethylene were studied by thermo-mechanical analysis. The purpose was to study the dimensional changes in polyethylene morphologies of extreme orientation. Dimensional changes were measured from -140 C to +70 C with a precision of better than 1%. A negative thermal expansion coefficient was observed along the length (c axis) of the fibers containing the polyethylene morphologies of extreme orientation. A change in negative coefficient is observed between -35 and -45 C. The sign and magnitude of the expansion coefficient confirm, along with other evidence, the existence of extended chain structures in these morphologies. A series parallel model has been developed for the ultradrawn polyethylenes to describe the dimensional changes with temperature. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1977
Accession Number
ADA040442

Entities

People

  • Numa J. Capiati
  • Roger S. Porter

Organizations

  • University of Massachusetts Amherst

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  • Modulus Of Elasticity
  • Polymers
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  • Thermal Expansion
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