Investigation of the microscopic origins of the torque and normal force responses of glassy polymers

Anny Flory, Gregory B. McKenna

Research output: Contribution to conferencePaperpeer-review

Abstract

Under the assumption that glassy polymers are incompressible, the mechanical response of a cylinder of viscoelastic material below the glass transition temperature to a torsional deformation consists of a torque response and a normal force response along the axis of the cylinder. In performing stress relaxation experiments on poly(n-alkyl methacrylate)s, the normal force required to keep the constant deformation is compressive and large. Here we examine the microscopic origins of the nonlinear response functions. We consider the influence of the secondary, sub-vitreous β relaxation on the normal force response. This is done by performing experiments on poly(methyl methacrylate) (PMMA) and poly(ethyl methacrylate) (PEMA) which both exhibit a β peak in the loss modulus as a function of temperature located at the same temperature of 10°C and having about the same intensity. A surprising result is that although the torque response for the PMMA is 50% higher than for the PEMA, the normal force response for the PMMA is 20% lower than the normal force response of the PEMA at the experimental temperatures of 45°C and 30°C.

Original languageEnglish
Pages1979-1983
Number of pages5
StatePublished - 2004
EventANTEC 2004 - Annual Technical Conference Proceedings - Chicago, IL., United States
Duration: May 16 2004May 20 2004

Conference

ConferenceANTEC 2004 - Annual Technical Conference Proceedings
CountryUnited States
CityChicago, IL.
Period05/16/0405/20/04

Fingerprint Dive into the research topics of 'Investigation of the microscopic origins of the torque and normal force responses of glassy polymers'. Together they form a unique fingerprint.

Cite this