Research On The Pretreatment And Dyeing Of Polylactic Acid/Richcel/Bamboo Fiber Blended Fabric

One-pot pre-treatment, disperse/reactive dye one bath dyeing and ultrasonic dyeing are proposed in this thesis.One-pot pre-treatment with high efficient desizing enzymes is used to desize the blended fabric.The single factor analysis and orthogonal test are used to study the dosage of desizing enzymes, hydrogen peroxide, scouring agent, pH value, the holding temperature and time, according to the breaking strength, the whiteness and the weight loss rate, and the optimum technological parameters are gained. Hydrogen peroxide and temperature are the important factors in the pre-treatment. The pH value of solution after pretreatment is about 6.87.The suitable disperse dyes and reactive dyes for one bath dyeing are screened. Through the comparison of mixed dyes, disperse dyes and reactive dyes in the PLA/Richcel/bamboo fiber blend fabrics in one bath dyeing by using the dye-uptake rate, K/S value and the soaping color fastness, the one bath dyeing conditions of the blended fabric are optimized.Ultrasound is applied in the disperse dyeing for PLA fiber of the blended fabric. The ultrasonic dyeing process is optimized by comparing with the conventional dyeing. By using SEM, DSC, XRD, and other means, the influence of ultrasonic treatment on dye bath and fabrics are studied. The results show that ultrasonic acoustic cavitation has influence on dyeing and the role of ultrasound on the fabric is not obvious. Most of disperse dyes suit for ultrasonic dyeing. The ultrasonic dyeing in PLA fiber can increase the dye-uptake of disperse dyes and K/S value. The K/S value can increase 16.03% than conventional dyeing. Under ultrasound, the glass transition temperature of PLA fiber and a crystals has no change. And crystallinity of this fiber rises.