Research On Pet/Pa Interwoven Melt Velcro And Its Mechanical Model

In this paper,PET/PA interwoven melt Velcro which can be used in water for a long time is researched and developed,including the optimization of the processing technology,the design of the structure parameters and the performance evaluation.At the same time,the mechanical model of Velcro is established,which can be used to calculate and predict the strength of Velcro.The processing technology is studied.The results show that the optimum parameters of the weaving process are as follows: the power of the far-infrared heater is kept at 200 W,the height of the heater is 5cm and the speed of the loom is 638r/min;the optimum parameters of the hot-melt process are as follows: the hot melt temperature is 140-150?,the hot-melt time is 50 min.The optimal parameters of the hook-cutting process are as follows: preheating temperature is 120 ? and preheating time is 10 s.Through the analysis of the structure of Velcro,six kinds of PET/PA interwoven melt Velcro with different structural parameters are designed.The results show that the optimal case whose mechanical property is the best is the hook arranged density in weft being 1 hook?4 warps and the hook arranged density in warp being 1 hook?3 wefts.The larger the hook density and hooking rate is,the better the mechanical properties becomes and the firmer the product is..The changes of performance are researched on PET/PA interwoven melt Velcro,nylon Velcro products with thermal fuse and PET/PA interwoven Velcro impregnated in water,acid and alkali.The results show that the performance of PET/PA interwoven melt Velcro is the best.The flexural length,permeability and wicking height of PET/PA interwoven melt Velcro and PET/PA interwoven Velcro are tested.The results show that PET/PA interwoven melt Velcro with contact comfort and wet comfort are better than PET/PA interwoven Velcro.The flexural length is smaller and it feels softer.The permeability and the wicking height are higher,the permeability and the wetting performance are better.It can be seen,the comfort of the former is better than the latter.The single-hook mechanical models of PET/PA interwoven melt Velcro are established,and mechanical models of peel and shear strength of Velcro are deduced.By modifying and simplifying parameters of the mechanical models,the formula between peel strength and the arrangement density of hooking is obtained,so is the formula of shear strength.That is to say,the formulas of peel and shear strength of Velcro are obtained.Through the coefficient of correction,the error percentage of theory strength to practical strength is less than 5%,so the formulas can be used to calculate the strength of such Velcro within the valid range.