Development Of High-strength And High-modulus Polyethylene Fiber Sewing Threa

Ultra-high Molecular Weight Polyethylene Staple Fiber(UHMWPE)is a kind of high performance fiber with strategic significance.It has excellent comprehensive performance and is widely used in military,biomedical and marine engineering fields.At present,the application of UHMWPE fiber in textile field is mostly filament products,and the research and application of UHMWPE fiber in short fiber spinning are in the initial stage.In this paper,UHMWPE staple fiber was taken as the research object,and its pure spinning and blending processes were studied from the perspective of spinnability,and UHMWPE staple fiber sewing thread was developed.The issue starts with the basic properties of UHMWPE staple fibers,and tests and analyzes various properties of UHMWPE staple fibers.The study found that the UHMWPE short fiber has a slightly grooved longitudinal surface and an oval crosssection,which is a high-strength and low-stretch fiber.However,its small friction factor,poor cohesion,large mass specific resistance,and poor heat resistance have a negative impact on spinning,resulting in severe static electricity during spinning,poor sliver uniformity,and inability to spin at high speed.On the basis of the research on fiber properties,the preparation process of UHMWPE short fiber blended yarn and the influence of blended yarn type and blending ratio on the properties of UHMWPE blended yarn were discussed.After pretreatment of raw materials,ring spinning was adopted and reasonable process parameters were selected to prepare UHMWPE short fiber pure spinning and five proportions of UHMWPE / PET and UHMWPE / PA6 blended yarns.The blended ratios were 50/50,60/40,70/30,80/20 and 90/10,respectively.The yarn density was designed to be 14.8tex.The basic properties of the prepared yarn were tested and studied.It is concluded that the pure spinning of UHMWPE short fiber is difficult,and the comprehensive properties of UHMWPE / PET and UHMWPE / PA6 80 / 20 blended single yarn are the best.Under the same blending ratio,the breaking strength of UHMWPE / PA6 blended yarn is lower than that of UHMWPE / PET blended yarn,because the breaking strength of PET staple fiber is higher than that of PA6 staple fiber,and the basic properties of PA6 staple fiber and UHMWPE staple fiber are more similar.Therefore,in addition to breaking strength,other properties of UHMWPE / PA6 blended yarn are better than those of UHMWPE / PET blended yarn.In order to develop UHMWPE staple fiber sewing thread,36 kinds of strands with three twists and two stranding methods were spun from the single yarn with two raw materials and three blending ratios obtained from the experiment.From the perspective of application,the basic properties of the sewing thread were tested and analyzed.According to the single yarn performance and stranding process,the basic properties of2-strand sewing thread and 3-strand sewing thread were comprehensively evaluated by grey cluster analysis method,and 36 kinds of strands were successfully divided into good,medium and poor grades.It was concluded that the basic properties of UHMWPE/ PA6(70/30)yarn with 70 twists / 10 cm were the best among the 2-strand sewing thread.Among the three stranding sewing threads,UHMWPE / PET(90/10)with 80 twists / 10 cm has the best comprehensive performance.The reason is that the fracture strength of UHMWPE / PET single yarn is relatively high,and the stranding process improves the basic properties of the yarn.Based on the above conclusions,it is recommended that the two-legged sewing thread of UHMWPE / PA6(70/30)with 70 twists / 10 cm is used for shoes,and the three-legged sewing thread of UHMWPE / PET(90/10)with 80 twists / 10 cm is used for bags.