Robert S. Irwin

OPTICALLY ANISOTROPIC MELT FORMING COPOLYESTERS

Polyimide-esters and filaments prepared from 4-(4'-carboxyphthalimido)benzoic acid or 4-(4'-hydroxyphthalimido)phenol

Polyimide-esters and filaments

Aromatic polyester which forms optically anisotropic melts and filaments thereof

Polyesters derived from 3,4'-dihydroxy-benzophenones or 3-hydroxy-4'-(4-hydroxyphenyl-)benzophenone and certain aromatic dicarboxylic acids and filaments thereof

Polyester which exhibits anisotropy in the melt containing p-oxybenzoyl units and 4,4'-dioxybenzophenone units or methyl and chloro derivatives thereof

Filament of polyimide from pyromellitic acid dianhydride and 3,4'-oxydianiline

Polyester which exhibits anisotropy in the melt containing p-oxybenzoyl units and 4-oxy-3'-carbonylbenzophenone units or methyl and chloro derivatives of said units

Preparation of aromatic polyamide having pendant carboxyl groups

Aromatic polyester consisting essentially of p-oxybenzoyl units, terephthaloyl units, 2,6-dioxynaphthalene or 2,6-dioxyanthraquinone units and m-oxybenzoyl or 1,3-dioxyphenylene units