Development Of High Elastic Nonwovens For Non Woven Roller

In the production and processing of strip,the most important production process to improve the appearance quality of strip is plate cleaning,and the main tool in the process of plate cleaning is squeezing roll.The squeezing roll material currently used in China is generally rubber or metal,but the squeezing roll of this material will greatly reduce the squeezing effect due to its lack of pores and non water absorption defects.Therefore,foreign countries invented a kind of special material roller-nonwoven roller,which is characterized by good squeezing effect,long service life,easy removal and replacement.The domestic research on the squeezing roller is more focused on the structure of the roller.This topic mainly studies the nonwovens used for nonwoven roller.The purpose of this project is to develop a kind of high elastic nonwovens for non-woven roller.In the early stage of the project,PTT fiber,PBT fiber,T400 fiber,ELK fiber and low melting point 4080 fiber were selected.Through pre-experiment,PTT fiber and low melting point polyester 4080 fiber were selected as the final raw materials of the project.Then the needling process and hot rolling process were optimized by orthogonal experiment,and the needling hot rolling composite nonwovens were prepared by using the optimized process parameters.In order to make the nonwovens used for non-woven roller have good elasticity,acid and alkali resistance and suitable stiffness,the post-treatment was carried out.The type of adhesive and application method were determined in the early stage,and then the post-treatment process was optimized by response surface method.Finally,the high elastic nonwovens used for non-woven roller were prepared,and their properties were tested.The conclusions are as follows:(1)The final structure of the product is surface middle layer surface layer.The preparation process of the surface layer and the middle layer is as follows:raw material preparation?loosening?cotton box?carding?mesh laying?pre needling.Then the surface layer and the middle layer are combined by needling and hot rolling,and finally the final high elastic nonwoven material for non-woven roller is formed through elastic finishing.(2)The needle punched nonwovens were prepared with PTT fiber and low melting point 4080fiber.The unit area mass of the needle punched nonwovens was 320g/m~2.The orthogonal experimental design was carried out with fiber proportion,needle punched density and needle punched depth as factors,and fracture strength,crease recovery angle and water absorption as evaluation indexes.The optimized needle punched process of the high elastic nonwovens for non-woven roller was that the surface PTT/4080 was 90/10,and the middle layer was pure PTT,the needling density was 150 thorns/cm~2 and the needling depth was 8 mm.(3)The needle punched nonwovens were hot rolled.Taking hot rolling temperature,roll spacing and roll speed as factors,crease recovery angle and water absorption rate as indexes,the orthogonal experimental design was carried out.Finally,the optimal hot rolling process of high elastic nonwovens for non-woven roll was determined as follows:hot rolling temperature was 150?,roll spacing was 1 mm and roll speed was 1.68 m/min.(4)The needle punched hot-rolled nonwovens were finished with waterborne polyurethane/acrylate finishing agent.The elastic finishing process of Nonwovens for nonwovens roller was designed and optimized by response surface method,and the regression equation was established.The regression model has high fitting degree,and can accurately predict the crease recovery angle and water absorption of finished nonwovens.The influencing factors of crease recovery angle are adhesive content,drying temperature and drying time,and the influencing factors of water absorption are adhesive content,drying time and drying temperature.The optimized finishing process parameters are as follows:binder content is 10%,drying temperature is 109?,drying time is 43 min.(5)In this project,the performance indexes of the prepared high elastic nonwovens for non-woven roller were tested:the mass per unit area is 360g/m~2,the thickness is 1.02 mm,the crease recovery angle is 173°,the water absorption is 329.5%,the wicking rate can reach 286.2mm/min in a short time,the breaking strength is 580N,the tear strength is 400N,the pore size distribution is uniform,the air permeability is 862.1mm/s,good wear resistance and compression resilience,good acid and alkali resistance,thermal stability and good stiffness.The high elastic nonwovens developed in this paper can meet the performance requirements of roller nonwovens.There are 38 figures,33 tables and 105 references.