Study On The Spinning Process Of Polysulfonamide Yarn Made By Different Fiber Length

Polysulfonamide (PSA) fiber is a new flame-retardant fiber which has excellent heat resistance, thennal stability and thermal oxidation, it is developed by China independently, but the fiber has high VSR(volume specific resistance) and initial modulus, instability of crimp and low friction coefficient of the fiber, which contribute to many troubles in its process of spinning, weaving and dyeing, and also limits the applications of PSA fiber.In this paper, according to the problems mentioned above and considering the influence of the fiber length on the yarn properties, the spinning processing of polysulfonamide fiber with different length were carried out and compared, which will be helpful for the processing and further application of PSA. Nowadays, the study of spinning process is mostly focus on the PSA staple fiber. The spinning process of medium-length or longer PSA fiber is rarely researched. Therefore, In this study, PSA filament will be stretch breaking into different length and at the same time form the tops with the fiber length of the 60mm,70mm,80mm,90mm,100mm. The process including stretch breaking, blending, drawing, roving and spinning. By testing the strength, evenness and hairiness of the yarn, we try to find out the best coefficient of twist and the best spinning length of polysulfonamide. The main experiments are shown as follows:(1) The resistance and the friction coefficient of polysulfonamide fiber were tested with the fibers added with five different oil solution made of four negative ion antistatic agent and a positive ion.(2) Spinning of five polysulfonamide fibers with different length under the different coefficient of twist(270,300,330 and 360). The strength, evenness and hairiness of each kind of yarn were tested to find the optimal fiber length and coefficient of twist.(3) Polysulfonamide filament was stretched breaking into four different length(55mm,60mm, 65mm,70mm) near the optimal spinning length. The polysulfonamide fiber were spun with the different twist factors with 330 and 360, to find out the optimal length of polysulfonamide fiber for spinning processing.On the base of the experiments, the result can be concluded as follows:(1)The resistance of polysulonamide fiber is decreased significantly when the oil solution added to polysulonamide fiber. Besides, the more the oil solution is, the lower the resistance is. The negative ion is better. (2) The strength of yarns spinned with five different polysulfonamide fiber are increase at the first and then decrease. The optimal twist is 330 and the strength and the comprehensive performance of the polysulfonamide fiber with the length of 60mm are the best When the coefficient of twist is 330.(4) The best coefficient of twist is 330 and the optimal length is 55mm, in according to compare the comprehensive process of yarns spinned by four different length(55mm,60mm, 65mm,70mm).