Study On Flame Retardant Property Of Waste Felt With Optimized Moulding Process

With the improvement of people's economic conditions and the change of consumption patterns,the speed of textile renewal is getting faster and faster.At the same time of the sharp increase in demand,the life cycle of products is also shortening.It is expected that by 2020,the accumulation of waste textiles in China will be as high as 2 billion tons.Lack of resources and environmental pollution are two major problems faced by mankind today,and they are also urgent problems to be solved.Actively dealing with waste textiles is of great significance in alleviating resource constraints,energy conservation,emission reduction,and environmental improvement.In order to realize the reuse of waste fabrics,this study uses the joint opening line to pre-treat the waste textiles,and recycles the waste polyester-cotton fabric into waste polyester and waste cotton fiber,which can be used in the non-woven process.These waste fiber are mixed with the low-melting polyester staple fiber and recycled polyester fiber by different proportions.The waste textile materials are prepared by mechanical carding and hot air bonding.The relevant process parameters include raw material ratio,hot baking temperature,hot melting time and molding pressure.The single-factor and orthogonal test group schemes were designed to prepare the felt which are made of waste textiles,and the production process was optimized by analyzing the basic performance test results.This material can be flame retardant after adding the flame retardant powder and the flame retardant liquid.Choosing an effective and economical plan to produce flame retardant waste textile felt.Finally,the material is subjected to the CONE test.Through this series of experiments,analysis and exploration:1.Waste textiles can be recycled into waste fibers after being sorted,disinfccted,opened,cut,combed,and can be used as raw materials for the production of waste felt.The tensile breaking strength and bursting strength of the waste felt increase with the increase of the content of low melting point polyester staple fiber in the raw material With the increase of hot baking time,hot melting temperature and molding pressure,the tensile breaking strength and bursting strength are increased first and then decreased.2.The thermal resistance of the waste textile felt of single factor and orthogonal test group is greater than 0.29m2·K/W,the thermal conductivity is less than 0.04W/(m·K),and the thermal insulation rate is higher than 84%.This felt is a high-efficiency thermal insulation material The more the waste polyester and cotton fiber are used,the better the insulation effect.3.The test results of tensile breaking strength and bursting strength of waste felt in orthogonal test group show that the order of influence of factors on the tensile breaking strength and bursting strength of waste felt is raw material ratio>hot baking temperature>molding pressure>hot melting time,the ratio of recycled polyester fiber:waste fiber:low melting polyester fiber is 20:50:30,hot baking temperature is 185?,hot melting time is 11min,forming pressure is 0.3MPa,which is the best moulding process.The tensile breaking strength of the waste textile felt is about 480N,and the bursting strength is about 1082N,the heat retention rate was 87%,and the compression modulus was 88MPa.4.The limiting oxygen index of waste textile felt after finishing by powder flame retardant is up to 21.8%,which does not reach the flame retardant standard and will cause strength loss.Different concentrations of ammonium polyphosphate flame retardant solution were selected to treat the waste textile felt by one dipping and one rolling process.As the concentration of the flame retardant liquid increased,the weight gain rate of the material became larger,and the flame retardant effect was better.When the concentration was higher than 400g/L,the limiting oxygen index can be higher than 25%and reach the flame retardant three-level standard.5.After immersing the waste textile felt in a phosphorus-nitrogen composite flame retardant with a concentration of 450g/L for 2h by a dip-and-roll method,the material has the best comprehensive performance and tensile breaking strength is about 400N,the bursting strength is about 897N,the flame retardant mechanism of the material is condensed phase and gas phase flame retardant,its limiting oxygen index can reach 32.6%,the average burning length in the vertical burning test is about 97mm,no afterburning and smoldering occur.It's a flame retardant B1 grade material.The test and analysis of this study provide a theoretical reference for the use of waste textiles to prepare waste felt materials,which has important practical significance for improving the recycling rate of waste textiles.