Evaluation of a Manufacturing Technique of Polyamide Bamboo Charcoal/Polyurethane Complex Yarns and Knitted Fabrics and Assessment of their Electric Surface Resistivity

[[abstract]]In this research, bamboo charcoal polyamide / polyurethane (BCP/PU) complex yarns and knitted fabrics were produced from bamboo charcoal polyamide textured yarn and polyurethane fibres. The polyurethane fibres were expanded and then wrapped with the bamboo charcoal polyamide textured yarn. Three manufacturing parameters were depicted as follows: the speeds of the rotor twister were 4000-12000 r.p.m., the wrapped counts of the BCP/PU complex yarns - 200 - 400 turns/m; and the expanded multiple of the polyurethane fibres was 3. Afterwards we fabricated BCP/PU complex knitted fabrics using a circular knitting machine. The tenacity of the BCP/PU complex yarns was 37258.4 cN/tex when the speed of the rotor twister was 4000 r.p.m. and the wrapped counts - 200 turns/m. Meanwhile, the elongation of the BCP/P complex yarns was 35.77% when the speed of the rotor twister was 4000 r.p.m. and the wrapped counts - 400 turns/m. The lower electric surface resistivity of the BCP/PU knitted fabrics was 3.33x10E10 (omega/Square) when the wrapped counts were 400 turns/m and the polyurethane fibres - 78 dtex. Moreover, when the wrapped counts were 200 turns/m, the optimum air permeability of the BCP/PU complex knitted fabrics with 44 dtex polyurethane fibres was 47.2 cm3/cm2/s, which was better than that with 78 dtex polyurethane fibres