Fibers and films of improved flame resistance
AssigneeE. I. Du Pont de Nemours and Company
InventorsRobert V. Kasowski, Kiu-Seung Lee
Life of this patent
Estimating the term…
Abstract
Aramid and polybenzimidazole fibers and films of improved flame resistance are obtained by impregnation with tungsten hexachloride.
Claims6
A method for preparing a fiber or film of improved thermal stability comprising impregnating the fiber or film with a solution of tungsten hexachloride in an organic solvent in sufficient amount to provide at least 0.1% by weight of tungsten, treating the impregnated fiber with an aqueous solution to extract solvent and to convert the hexachloride into mixed tungsten oxides wherein the polymer forming the fiber or film is selected from the group consisting of an aramid and polybenzimidazole.
A method for preparing aramid fiber or film of improved thermal stability comprising dissolving the tungsten hexachloride in a solution of polymer in an organic solvent, forming the solution into a fiber or a film, treating the fiber or film with aqueous solution to extract the organic solvent and to convert the tungsten hexachloride into mixed oxides of tungsten.
Dependencies are inferred from the claim text.