Accession Number:

AD0669497

Title:

LABILE CROSSLINKS IN LOW UNSATURATION ELASTOMERS, II. EFFECT OF CHAIN AND CROSSLINK STRUCTURE ON THERMAL AND OXIDATIVE STABILITY,

Descriptive Note:

Corporate Author:

PRINCETON UNIV N J FRICK CHEMICAL LAB

Report Date:

1968-04-01

Pagination or Media Count:

35.0

Abstract:

The thermal and oxidative stability of low unsaturation elastomers was studied as a function of chain and crosslink structure by stress relaxation and oxygen absorption techniques. An ethylene-propylene-terpolymer, a propylene oxide copolymer, and an ethylene sulfide-propylene sulfide-terpolymer were used. The thermally labile polysulfide crosslink that results from sulfur cures is a potent antioxidant. The thermal lability is ascribed to an interchange mechanism, with an activation energy of 24 kcalmole between 100 and 150C. The presence of an atom of oxygen in the chain results in an increased susceptibility to oxidative degradation compared with a hydrocarbon chain. The presence of a sulfur atom in the polymer chain confers a sensitivity to a destructive attack by the active ingredients and products of an accelerated sulfur curing recipe. Author

Subject Categories:

  • Polymer Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE