Optimization of electroflocculation of yarns

Abstract

The empirical equation obtained can be used for designing a flocculated yarn with a given nap cover density. The optimum values of the process parameters for applying nap established as a result of the studies can be the basis for RFPs for designing and manufacturing the unit and process for electroflocculation of yarns.The essence of yarn electroflocculation technology consists of application of short-cut (0.5-1.5 mm in length) specially processed chemical yarns on adhesive-coated core yarn [1]. The area of application of the flocculated yarns and items made from them is for household and industrial textiles.We developed the optimum process conditions for application of nap to an adhesive-coated core yarn. The experimental setup assembled in the research laboratory for Friction Processes in Spinning in the Department of Wool Technology was used to fabricate the flocculated yarn. The setup contained units for unwinding the core yarn and applying the adhesive, a flocculation chamber, a drying chamber, a device for winding the yarn on a cylindrical bobbin, and a kinematic unit [2].The components of the flocculated yarn were polyamide complex elastic core yarn with a linear density of 15.6 tex; dyed polyamide floc with a linear density of 0.33 tex and average length of 1 mm, diameter of 0.019 mm, and 4% moisture content; adhesive -a three-component composite based on the water-dispersion adhesive system Tubvinyl LC 274 H-N and Tubassist Fix 106 W from CHT (Germany): 48% adhesive made from acrylic resin; 16% fixative (pH regulator); 36% distilled water. The characteristics of the composite are: initial viscosity of 9.3 Pa⋅sec; mass fraction of nonvolatiles (dry residue) of 20%; pH 7.5-8; exposure time of 2 min; ionogenicity: cation-active; conductance of 0.6⋅10 -2 Ω -1 ⋅cm -1 . The electroflocculation process was optimized with a two-factor experiment with a Kono matrix.Nap density n (1/mm 2 ) -the number of fibres per 1 mm 2 on the surface of the core yarn -was used as the optimization criterion Y. The nap density is a characteristic quantitative measure of the optimality of electroflocculation and is a function of the degree of orientation of the fibres in an electric field -was used as optimization criterion Y. On the other hand, the wear resistance of the flocculated material is a function of the nap cover density, and in this sense, the nap density is the most important qualitative characteristic [1].The specific floc consumption P sp [g/(sec⋅m 2 ] -the mass of floc fibres fed per second per area of flocculator feed grating, and working voltage U (kV) fed to the flocculator charging electrode were selected as input factors X 1 and X 2 . These factors are the most important physical process parameters directly in the flocculation working zone which affect the density of formation of the nap covering on the flocculated yarn.The specific floc consumption was regulated by varying the vibration frequency of the flocculator in the flocculator grating with 0.8 × 0.8 mm cells. The voltage on the flocculator charging ele...