Multilayer Composite Spunlace Nonwoven Technology And Product Performance Research

With the rapid development of spunlaced nonwovens,the market scale of spunlaced nonwoven products has grown rapidly.Many spunlaced nonwovens have focused their attention on highspeed and highyield spunlaced nonwoven production lines,among which the multilayer composite spunlace technology has become the research focus and development trend in recent years by virtue of its high speed,high production,simple process and high profit margin.This topic takes the multilayer composite spunlace technology as the basic starting point.Combining the development background,current situation of spunlaced nonwoven technology and the application field of spunlaced nonwoven materials,this paper focuses on the basic principle and technical characteristics of the parallel composite spunlaced nonwoven technology of multilayer web,and analyzes the effect of the mechanical characteristics of the spunlace equipment,the structural properties of the nonwoven fiber material and the different spunlace composite processes on the the structure and properties of the spunlaced nonwoven products.Through the above research and analysis,the main conclusions formed include:(1)In the multilayer parallel composite spunlace technology,the carding machine is linearly arranged,and the direction of the"fiber flow"in the web and the angle between the direction of the longitudinal fibers in the composite web and the x-axis of the reference coordinate system are both0°.In the carding system,considering the fiber distribution coefficient and the combing degree is an effective method to characterize the actual carding effect of the main cylinder combing unit and the carding machine.In the spunlace reinforcement system,according to the force condition of the fiber micro-element,the web relies on the centripetal force provided by the internal vacuum suction device of the hydroentangled drum to realize the active transfer of the web on the surface of the drum.(2)In the analysis and calculation of energy consumption cost,the electricity cost per ton of spunlace nonwoven fabric is about 0.2 tons of standard coal,and the cost ratio is more than 65%.In the line speed range of 100-200m/min,the linear line speed increases by 20m/min,and the total energy consumption of the dryer per unit time increases from 6.5%to 15.7%,and the growth rate gradually decreases;The amount of gas required per ton of spunlaced nonwoven fabric is reduced from 3.7%to 4.5%,and the rate of decrease is gradually reduced.The recycling rate of the backwash water recovery unit in the water circulation and filtration system can reach 70%,and the overall water consumption is reduced by 30%.The total power range of the suction fan and the high pressure pump is 1250-1400Kw,which accounts for 70%-80%of the total power consumption.(3)According to the structural specifications of the portal frame structure and the load specification of the building structure,before the installation of the spunlace machine,the bearing capacity of the foundation needs to reach 252.42k Pa.Compared with the traditional rectangular rigid frame structure,in the new trapezoidal rigid frame structure,the mid-span bending moment of the inclined beam is 36.09k N/m,and the shearing force is 49.21k N and 47.14k N respectively.The overall stability of the rigid frame structure is excellent.However,the compression deformation of the front corner column is obvious.The structural design can be strengthened by adding structural beams or concrete pouring to ensure the stability of the front corner column.(4)According to the test results of 13 kinds of different raw material ratios and spunlace nonwoven fabrics with different areal densities,it is analyzed that when the gram weight is the same,the amount of polyester fiber in the spunlace nonwoven fabric increases by 10%,and the growth of longitudinal strength is about 15.15N,the lateral strength increase is about 4.08N,the entanglement coefficient is increased by about 0.50 N/g/m~2;when the raw material ratio is the same,the gram weight of the spunlaced nonwoven fabric is increased by 5g/m~2,vertical The strong growth is about17.28N,and the lateral strength is about 5.79N.When the surface density of the spunlaced nonwoven fabric is 45g/m~2 and the viscose fiber and the polyester fiber are mixed as a fiber raw material in a ratio of 2:8,the longitudinal and transverse strength ratio of the spunlaced nonwoven fabric is 3.47,and the areal density is 3.The CV value is 1.2%,the entanglement coefficient is 3.51,and the overall performance of the product is excellent.According to the test results of spunlaced nonwoven fabrics of 6 different web composite methods,in terms of physical properties,the multilayer cross-composite spunlaced nonwoven fabric has good uniformity,the minimum areal density CV value is 1.0%,and the minimum thickness is CV.The value is 0.5%;In terms of mechanical properties,the longitudinal and transverse strength ratio of the multilayer cross-composite spunlaced nonwoven fabric is relatively small,the minimum value is 1.72,and the elongation at break in the longitudinal and transverse directions is substantially the same;In terms of capillary effect,the gap between the longitudinal and transverse wicking heights of the multilayered parallel composite spunlace nonwoven fabric gradually increases with time,with a maximum difference of 60 mm,and the vertical and horizontal gaps of the multilayer cross-composite spunlace nonwoven fabric will gradually shrink.The minimum difference is 3mm,and under the same areal density conditions,the capillary effect of pure viscose spunlace nonwoven fabric is obviously better than that of spunlaced nonwoven fabric with other fiber raw material ratio,and the wicking height can reach 140mm in 10min;In terms of pore size distribution,the average cross-sectional diameter of the multilayer cross-composite spunlaced nonwoven fabric is about40μm,and the average cross-sectional diameter of the multilayer web parallel composite spunlace nonwoven fabric is about 50μm;Influenced by the pore size distribution,the gas permeability and moisture permeability of the multilayer web parallel composite spunlace nonwoven fabric are obviously superior to the multilayer cross-composite spunlace nonwoven fabric in terms of gas permeability and moisture permeability.The maximum gas permeability is 1035mm/s,and the maximum moisture permeability is 23g/(m~2·24h).