Preparation and properties of multifunctional bio-based polyamide 56 composite fibers
Multi-functional bio-based ZnO/bio-based polyamide 56(PA56)composite fibers were prepared from introduction of nylon 6 with excellent spinnability into matrix PA56 with nano ZnO(nano-ZnO)as modified particle by a two-step melt spinning technology,and characterized by SEM,FTIR,XRD,DSC and TGA.The effect of nano-ZnO mass fraction on the properties of ZnO/PA56 composite fibers were then analyzed.The results showed that the nano-ZnO was uniformly dispersed in PA56 matrix by physical blending,with the heterogeneous nucleation of nano-ZnO reducing its mechanical properties and thermal stability while increasing its crystallization temperature.The ZnO/PA56 composite fibers with mass fractions of 0.5%,1.0%and 2.0%(noted as PA56-0.5,PA56-1.0 and PA56-2.0)exhibited an increment in crystallization temperature by 1.1~5.2 ℃,reduction in the largest weight loss temperature by 88.94~98.52 ℃,and decrease in breaking strength to 3.32,3.22 and 3.06 cN/dtex.The addition of ZnO significantly improved the antibacterial,thermal conductivity and UV resistance of the composite fibers.Both inhibition rates of PA56-0.5 on Escherichia coli and Staphylococcus aureus were 100%,which was obviously better than those of PA56(25%and 41%).The temperature of PA56-0.5,PA56-1.0 and PA56-2.0 could reach 137.0,136.0 and 128.0 ℃ when heated for 50 s,which was better than 121.0 ℃ of PA56.After 140 h ultraviolet irradiation,the fracture strength reduction rates of PA56-0.5,PA56-1.0 and PA56-2.0 were 73.2%,73.3%and 69.9%,respectively,lower than that of PA56(79.8%).