Study On Modification Of Cotton Fabrics With Natural Cationic Mass And Its Supercritical Carbon Dioxide Dyeing By Vegetable Dyes

Plant dyestuff originated from nature,has good environmental compatibility with Ecology biodegradable,and color elegant natural,It is harmless to human health,meeting the requirements of modern people pay attention to about their own health as well as environmental protection.But low dyeing rate and poor color fastness limits the application of natural dyes on cotton fabrics seriously.Traditional water bath dyeing uses a lot of auxiliaries and dyes,the waste water will pollute the environment.Based on the above problem,this paper applies the chitosan and regeneration of wool keratin to modify natural cationic on cotton fabrics,developing natural dyes supercritical CO₂ dyeing technology which based on fiber modification and improving the dyeing performance of natural dyes on cotton fabrics.This paper use chitosan and regeneration of wool keratin to modify cotton fabrics respectively,through analysis of the dyeing difference scope of the purple sweet potato pigment on modified cotton fabrics,discussing the effect of chitosan concentration,concentration of citric acid,curing temperature and liquid rate on modification;And modifing cotton fabric by traditional water bath and supercritical CO₂ dyeing.Through by discussing the effect of kinds of mordants and dyeing methods on the the traditional water bath,optimizing the optimum dyeing process;Through the analysis of the dyeing difference scope of the curcumin on modified cotton fabrics,discussed the effect of dyeing temperature,pressure,dyeing time and other factors on the performance of supercritical CO₂ dyeing on modified cotton fabrics,and the dyed cotton fabrics were characterized by infrared spectrum,X-ray diffraction,thermal and mechanical properties.The research shows that appling the chitosan and regeneration of wool keratin to modify natural cationic on cotton fabrics,Bring in theNH₂^- onto cotton fabrics,and make the modified cotton with NH₃⁺ ions attract between natural dye mainly in weak acid dye bath,to improve the dyeing performance of natural dyes containing anionic groups for the cotton fabrics.Optimized process of chitosan modified cotton fabric was: chitosan concentration 15g/L,citric acid concentration 100 g/L,cure temperature 140 ?,liquor detention 100%.Optimized process of regeneration of wool keratin was: citric acid concentration 100 g/L,cure temperature 140 ?,baking time 3 min,rolling over 100%.The color difference scope can be reached 46.65 and the K/S value of number can be reached 1.93 when using?-cyclodextrin one-bath dyeing.Natural curcumin can achieve good dyeing effect under the condition of dyeing temperature 120 ?,dyeing pressure 25 MPa,dyeing time 30 min,dye concentration of 3.6% and process conditions CO₂ flow 30 g/min.The ?E* and K/S value of the optimization technology of cotton fabrics modified by chitosan and regeneration of wool keratin could reached at 97.28/96.35 and 11.46/10.58,respectively.The washing fastness was rated at 4-5 and rubbing fastness was rated at 5 whichwill meet the requirements of color fastness.