Study on spinnability of polyacrylonitrile solution based on dynamics simulation of dry‐jet wet spinning

Spinnability of polyacrylonitrile (PAN) solution was studied based on the spinning dynamics simulation and dry‐jet wet spinning experiments. The spinnability phenomenon was observed from the extruding and extending spinning experiments. The suitable conditions of normal extruding and extending of the PAN solution were obtained and the critical spinnability conditions were simulated. The experimental and simulation results showed that pressure drop through the spinneret was similar, while the temperature, velocity, and velocity gradient through the spinneret of PAN solution changed dramatically. It suggests that pressure drop can be chosen as one of the spinnability criterion for solution extruding and filaments forming during dry‐jet wet spinning. Furthermore, the effect of spinneret parameters and spinning conditions on spinnability was simulated. It shows that spinneret entrance angle, outlet channel length and width have impacts on the pressure drop and the die swell ratio, which suggests the spinneret design can be optimized to regulate the spinnability according to the simulation results. It is also found that some bad situations of spinnability such as sticking phenomenon can be avoided by decreasing spinning temperature or increasing mass flow rate to increase the pressure drop at a certain level under the premise of extruding smoothly. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46377.