Research On The Properties Of Yarns Combined With Multiple-differential Polyester Filaments And Fabrics

In order to make marketable products for polyester filaments, it is a general trend to developnew varieties and high added value products, in the premise of lower production cost. It is amostly used method to develop new synthetic fiber products by changing fibers’ appearance andcross section, or using multicomponent and multifunctional fibers, etc. In this situation, researchon the new product development of combined yarns with multiple-differential polyesterfilaments is for the utilization of advanced technology. It can increase the added value ofpolyester filaments and also has some innovation. At the same time it can provide theoreticalbasis for the development of new varieties and production.This topic uses8.33tex PET filaments,8.33tex PTT filaments,7.78tex PA filaments,11.1tex PET filaments with triangle section and11.1tex PET filaments with cross section as rawmaterials, adopting network and coalesced twisting methods to process varieties of differentproportions of composite yarns. It contains PET/PTT and PET/PA bi-component compositeyarns, and profiled section composite yarns. Then make them into fabrics as well as T400fibers,CM800fibers and PET/PA*fibers. Make the fabrics heat-moisture treatment processing. Basedon testing and analyzing mechanical properties of raw materials and various composite yarns andfabrics, discuss the effect of the composite ratio, the composite way, air pressure and twist tomechanical properties of composite yarns and fabrics. Conclusions are as follows:(1) For PET/PTT composite yarns, the tensile curve of network filaments have two stressyield points; it’s the unique characteristics. With the increasing percentage proportions of PTTcomponent in network composite yarns, the fracture strengths decrease first and then increase,and the elongations at break increase first and then decrease. With the increaseing air pressures,the breaking strength and elongation both increase first, and then decrease. The air pressure ofnetwork processing can not be too big. The breaking strength and elongation of twist compositeyarns increase. With the increasing twists, their fracture strengths and elongations increase first,and then decrease. Their critical twists are smaller than the same fineness of short fiber yarns.Twist can not be too big. The elongation at break of PET/PTT composite filaments is bigger than T400fibers and CM800fibers, but strength is in between. The network and coalesced twistingcomposite methods can substitute bi-component composite spinning in a certain extent.Composite blended yarns have advantages of both PET fiber and PTT fiber.(2) For PET/PA composite yarns, their soft elasticities are poorer than PET/PTT compositeyarns. With the increasing percentage proportions of PA component, the fracture strengthgradually increases, the elongation at break increases first, and then decreases.With theincreasing air pressures and twists, the breaking strength and elongation both increase first, andthen decrease, and exist peak point. The breaking strength and elongation of PET/PA compositeyarns are bigger than PET/PA*.The property of PET/PA composite yarns is beyond the meltspinning.The network and coalesced twisting composite methods can substitute bi-componentcomposite spinning in a certain extent.(3) For profiled section polyester composite yarns, with the increasing percentageproportions of cross PET component, the breaking strengths decrease gradually and elongationsat break increase. With the increasing air pressures, the breaking strength and elongation of thenetwork composite yarns increase first, and then decrease. The wicking heights of compositeyarns decrease first, and then increase. The hygroscopicity of network yarns is superior to twistyarns. The air pressures of network yarns can not be too big in order to obtain superior wickingheight. The wicking height test can be set to20minutes.(4) For bi-component composite fabrics, with the increasing percentage proportions of thePTT of composite yarns, the permeability of PET/PTT composite fabrics gets worse; the airpressure has little influence on the permeability of composite fabrics; with the increasing twists,the permeability gets better. With the increasing percentage proportions of PA of compositeyarns, the permeability of PET/PTT composite fabrics decreases first, and then increases; withthe increasing twists, the permeability gets worse. For network and twisting composite fabrics,the permeability is better than corresponding bi-component composite spinning fabrics. Theelongation at break of bi-component composite fabrics has a linear positive correlation with PTT%or PA%. The breaking strength of PET/PTT composite fabrics gradually decreases, and ofPET/PA composite fabrics gradually increases. The air pressure and twist has little impact on thetensile properties of bi-component composite fabrics. The tensile property of PET/PTT composite fabrics is between T400fabrics and CM800fabrics. The PET/PA composite fabrics isobviously superior to the PET/PA*fabrics.(5) For bi-component composite fabrics, with the increasing air pressure and twist, theelastic recovery rate decreases, and the plastic deformation rate increases. With the increasingpercentage proportions of PTT of PET/PTT composite yarns, the plastic deformation rate offabrics increases, the elastic recovery rate of network fabrics decreases first, and then increases;the elastic recovery rate of twist fabrics increases first, and then decreases. With the increasingpercentage proportions of PA of PET/PA composite yarns, the elastic recovery rate and theplastic deformation rate increase. The elastic recovery rate of PET/PTT50/50composite fabric isminimal, but the loss elasticity and the increase plasticity are maximal; the elastic recovery of100%PA composite fabric is big, but its loss elasticity and increase plasticity is maximal; theelastic is not stable, and fabrics are easy to deformate. The elastic recovery of PET/PTTcomposite fabrics is between T400fabrics and CM800fabrics, and PET/PA composite fabricsare superior to PET/PA*fabrics made by bi-component composit spinning.(6) For profiled section composite fabrics, with the increasing percentage proportions ofcross PET, the air rate decreases, and it’s better than the same fabric specifications of cottonfabric and cotton ammonia core-spun yarn fabric; the breaking strength is linear negativecorrelation, and the elongation at break gradually increases.The breaking strength is significantlybigger than the same fabric specifications of cotton fabric and cotton ammonia core-spun yarnfabric, the elongation at break falls in between. The wet permeability gets better, and networkfabrics are superior to twist fabrics, cotton fabrics fall in between; the moisture permeation firstincreases, and then decreases; it’s bigger than clothing comfort moisture transmission minimum;compound ratio for triangle/cross33.3/66.7is optimal; glossiness and specular reflected lightintensity gradually decrease, and the diffuse reflected light intensity increases gradually; networkfabrics have better luster than twist fabrics; the glossiness is better than cotton fabric and cottonammonia core-spun yarn fabric, but the diffuse reflected light intensity is worse.