Fibers from aromatic copolyamides of limited order

Fibers were spun from six different, wholly aromatic copolyamides of limited order. Tensile properties of the fibers were obtained at standard conditions and, for selected fibers, at elevated temperatures and after heat‐aging at 300°C in air. The dry‐heat shrinkage determined up to 400°C on selected fibers was relatively low; zero‐strength temperatures ranged from 375°C to 495°C. Resistance to numerous chemical reagents was determined for one of the fibers and found to be comparable to that of the fibers from other wholly aromatic polyamides. Resistance to ultraviolet light appeared to be of the same order as that of unstabilized nylon 66.