Trifluoronitrosomethane/tetrafluoroethlylene elastomers dilute solution properties and molecular weight

Abstract

The copolymer prepared from tetrafluoroethylene and trifluoronitrosomethane was studied by light scattering in 1,1,2‐trichloro‐2,2,1‐trifluoroethane (Freon 113) and by solution viscosity in Freon 113 and perfluorotributylamine (FTBA). Molecular weights ranging from 2 × 105 to 2.4 × 106 were measured. Viscosity–molecular weight relationships were obtained for both solvents. They are: The extreme resistance of the polymer to nonfluorinated solvents is explained on the basis of its low solubility parameter, δ, which was established to be 5.2. From a consideration of the root‐mean‐square end‐to‐end chain length, the freely jointed segment is 24 chain atoms. Fractionation of the polymers shows a wide range of molecular weights with an abnormally large, low molecular weight portion.