Research Of Cationic Modification And Dyeing Properties With Acid Dyes On Linen Fibers

The modification of linen fibers and dyeing mechanism and dyeing properties ofmodified linen fiber were studied in detail in this paper.Theoretical analyze and prepare experiments have been done, to determine linen fiber ismodified with quaternary ammonium salt GTA. Through single factor and orthogonal test todetermine the optimum synthesis process of the modification agent for: reaction time is5hours, EPIC and TMA ratio of4.5:1, the reaction temperature is22℃, and the modificationagent is characterized.The optimum process of linen fiber modification is determined through single factor andorthogonal test: modifier dosage was45g/l, NaOH dosage was28g/l, modificationtemperature60℃, modified time is60min. The characterization analysis of modified linenfabric shows that the modified linen fabric grafted with quaternary ammonium groups, thecrystallinity is decreased, the amorphous zone is increased, and many dens and peel lossstreaks formed on the surface. These changes increased the dyeability of linen fabric, andmake it possible for the flax fibers to dye by acid dyes which could not done in normalcircumstances.The dyeing thermodynamics theory of modified line fabric dyed with acid dyes isinvestigated through drawing adsorption isotherms, the results indicate that dyeing of aciddyes on modified linen fibers accords with the characteristic of Langmuir adsorption isotherm.Research of the dyeing kinetics of modified linen fabric on the basis of dyeing rate anddiffusion rate indicates the dyeing rate of that modified linen fabric is faster, while it is easy tocause uneven dyeing, so we can dye with Low temperature or warming up gradually.Through the comprehensive analysis on the modified linen fabric characterization,thermodynamics, kinetic theory of the orthogonal test of modified linen fabric, the bestdyeing process of modified linen fabric is determined ultimately: liquor ratio is1:30, theamount of dye was9%(owf), NaCl dosage is20g/l, Na2CO3dosage is25g/l,40℃into thedye, followed by slow up to60℃for90min staining. And the dyeing properties of modified linen fabric was deeply studied, the resultsshowed that the modified linen fabric had better levelness and better color fastness or higherdye uptake.