Dry‐jet wet spinnability of poly(1,4‐phenylene‐1,3,4‐oxadiazole) fiber: The influence of polymer intrinsic viscosity and spinning dope temperature

Abstract

AbstractThe spinnability of poly (p‐phenyl‐oxadiazole) (POD) spinning dope was regulated by tuning intrinsic viscosity and temperature to make it feasible for dry‐jet wet spinning. An increase in intrinsic viscosity ([η]) and a decrease in temperature will give rise to a more significant entanglement density of the POD solution and increase viscosity. Results show that POD spinning dopes' stable extrusion can be formed at the conditions when the spinning dope's viscoelastic transition frequency (VETF) is around 10 Hz. The solution was selected to prepare POD fiber when [η] = 2.23 at 40 °C, and the tensile strength of the POD fiber was enhanced significantly (from 1.3 to 3.19 cN/dtex). The best mechanical properties were achieved when the draw ratio at the spinneret was 1.6. Our work provides an alternative for the rapid preparation of high‐performance POD fiber, which is of great significance for broadening the application field of POD fibers.