STRESS RELAXATION AND STRUCTURE OF HIGH TEMPERATURE ELASTOMERS

Abstract

Sol-gel relations in natural rubber vulcanizates have been studied both during network formation and degradation. The experimental values obtained during network formation, deviated markedly from theory, both as to magnitude and by showing an unexpected dependence on the primary chain length. It was shown that this deviation could be attributed to physical crosslinks, resulting from chain entanglements trapped during network formation. The total number of elastically effective chain entanglements per unit volume was found to be a function of the concentration of chemical crosslinks. The effectiveness of a chain entanglement was also found to be a function of the concentration of chemical crosslinks. The theoretical expressions of Horikx (J. Polymer Sci. 19:445, 1956) for network degradation were modified to include the effect of chain entanglements. (Author)

Document Details

Document Type
Technical Report
Publication Date
May 31, 1960
Accession Number
AD0250735

Entities

People

  • K.w. Scott
  • V.r. Allen

Organizations

  • University of Akron

Tags

DTIC Thesaurus Topics

  • Amorphous Materials
  • Degradation
  • Elastomers
  • High Temperature
  • Macromolecules
  • Materials
  • Molecules
  • Natural Rubber
  • Polymers
  • Rubber
  • Vulcanizates

Readers

  • Aerial Delivery - Logistics and Supply Chain Management.
  • Mathematical Modeling and Probability Theory.
  • Polymer Science and Engineering.