Controlled coagulation of rigid-chain polymer thin films

Abstract

A method for preparing optical quality, thin films of rigid-rod polymers and co-polymers, as well as blends of such polymers or co-polymers with flexible coil-like aromatic heterocyclic polymers and co-polymers which comprises (a) preparing a solution of the rigid-rod polymer or co-polymer or blend in a suitable solvent; (b) forming a film from the solution; (c) exposing the film to a non-solvent vapor for about 1 to 5 minutes per micron thickness in the finished film; and (d) coagulating the film in a non-solvent. This method can be employed to prepare films of high nonlinear optical susceptibility for electro-optical device applications. Because of their thermal stability, mechanical strength and chemical resistance, films prepared according to this method can also be used as filters and separation membranes.

Dependencies are inferred from the claim text.