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Journal of Materials Science

, Volume 35, Issue 2, pp 427–435 | Cite as

Rubber toughening of plastics Part XIII Dilatational yielding in PA6.6/EPR blends

  • C. B. Bucknall
  • A. Lazzeri
Article

Abstract

Tensile tests were carried out at both constant stress and constant extension rate on polyamide 6.6 blends containing 0–20 wt% of maleinated ethylene-propylene rubber (EPR-g-ma), using specimens conditioned at 50% RH. Longitudinal and lateral strain measurements on creep specimens showed that blends containing EPR-g-ma exhibited dilatation at tensile stresses above 27 MPa. This observation is consistent with the predictions of the particle cavitation model proposed in an earlier paper (A. Lazzeri and C. B. Bucknall, J. Mater. Sci. 28 (1993) 6799). In standard tensile tests on PA6.6/EPR-g-ma blends, cavitation preceded yielding (defined by the 1% offset strain). Creep and yield data obtained over a range of temperatures and strain rates were correlated using the Eyring equation. The onset of dilatation in these PA6.6/EPR blends was marked by a change in deformation kinetics, which is analysed using a modified version of Gurson's equation.

Keywords

Rubber Tensile Test Cavitation Tensile Stress Lateral Strain 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • C. B. Bucknall
    • 1
  • A. Lazzeri
    • 2
  1. 1.Advanced Materials DepartmentCranfield UniversityBedfordUK
  2. 2.Centre for Materials EngineeringUniversity of PisaPisaItaly

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