PHYSICAL AND RHEOLOGICAL PROPERTIES OF NITROSO RUBBERS
Technical Report,25 Jun 1965,24 Sep 1965
MONSANTO RESEARCH CORP DAYTON OH DAYTON
Pagination or Media Count:
Characterization of a trifluoronitrosomethanetetrafluoroethylene copolymer was continued. The molecular weight light scattering of a gum rubber fraction was determined to be 484,000 when examined in the perfluorocyclic ether solvent. Previous determinations on gums in perfluorotributylamine and Freon 113 indicated a molecular weight of 400,000 and 200,000, respectively. Respective intrinsic viscosities were 0.44, 0.41 and 0.18. Mold cure plus a stepped post-cure was found necessary in order to obtain adequately vulcanized samples. One part of carbon black in an amine-cured, SiO2-filled nitroso rubber increased strength and hardness to produce a rubber of 267 psi strength, 420 elongation and 47 Shore A hardness units. Dynamic modulus measurements indicate a utility for the rubber well below -75C. A white precipitate found in earlier gums was not conclusively identified except that it was shown to be chemically different from the typical nitroso gum.
- Polymer Chemistry