Characterization, Antistatic Treatment and Spinnability of Bio-based Polyamide 5,6 Staple Fibers

A new kind of bio-based polyamide 5,6 (PA56) fiber has been synthesized from adipic acid and 1,5-pentanediamine. In this report, the characterization, antistatic treatment, mechanical properties, moisture absorption, mass-specific electrical resistance, and static electricity of the PA56 staple fibers were investigated. The spinnability of the PA56 yarns was studied. The results showed that the breaking strength of the PA56 fibers was 3.55 cN·dtex−1, the breaking elongation was 61.60% and the initial modulus was 49.32 cN·dtex−1. The PA56 staple fibers had an excellent moisture absorption of 4.68% and the easy release of water from the fibers. The release of water absorbed on the staple fibers made the carding processing of the PA56 fibers difficult due to electrostatic aggregation. Thus, an antistatic treatment of the PA56 staple fibers was carried out. Compared with the untreated fibers, the treated fibers exhibited a spectacular improvement in conductivity which led to their high efficiency of carding and good spinnability. The potential of the PA56 staple fibers carding web decreased from +21.2 to +0.04 kv when treated. The mass-specific electrical resistance of the treated PA56 staple fibers decreased from more than 104 MΩ·g·cm−2 to 290 MΩ·g·cm−2 both at a relative humidity (RH) of 35%, and from 1500 to 9.5 MΩ·g·cm−2 both at a 65% RH. The Ring yarn and Siro-spun yarn were successful produced by their spinning systems. The measurement results of the yarns demonstrated that the Siro-spun yarn had better properties than the Ring yarn, such as tensile strength, unevenness (CV%), hairiness index (H) and abrasion resistance.