Study On Dyeing And Finishing Performance Of Bamboo Viscose Fiber

Bamboo viscose fiber as a kind of new fiber which has excellent performance, and the resource of bamboo is rich in China. The research on its dyeing and finishing performance provide both a theoretical basis for its development and application and a guideline for its dyeing and finishing process. In this paper, the influence of sodium hydroxide on the structure and weight loss of bamboo viscose was studied, the bleaching technics of bamboo viscose fibers using tetraacetylethylenedianime(TAED) as an activator of peroxide bleaching at low temperature were investigated. The adsorption behavior and dyeing mechanism of direct dyes, and the dyeing properties of reactive dyes on bamboo viscose fibers, as well as the ultraviolet protection finishing and anti-crease and anti-ultraviolet multifunctional finishing of bamboo viscose fibers were studied. By these basic researches, the results were obtained as follows:(a) The weight loss of bamboo and conventional viscose fibers during caustic treatment indicated that the alkali resistance of bamboo viscose fibers was not good and poorer than that of conventional viscose fibers. Afrter caustic treatment, the direct dyeing kinetic of bamboo viscose fibers were enhanced.(b) Considering the disadvantage of bamboo viscose fibers such as low whiteness, low wet strength and poor alkali resistance, TAED was used as an activator for the peroxide bleaching of bamboo viscose fibers. This bleaching method can be used to solve the problem of the low whiteness of bamboo viscose fibers.(c) Bamboo viscose fibers displayed slightly higher dyeing rates and dye absorption values at initial stages, but rather lower equilibrium absorption values than conventional viscose fibers. Three equations, namely Chrastil, Cegarra-Puente and Vickerstaff, were used to fit the direct dyeing kinetics of bamboo viscose and conventional viscose fibers, showing that the best result was obtained by Chrastil's equation. Different from conventional theories, the adsorption of direct Yellow 86 and Orange 39 on bamboo viscose fibers were best obtained by Redlich-Peterson equation.(d) The dyeing performance of three dyes having different reactive groups for bamboo viscose fibers were almost the same as that for conventional viscose fibers. The SERF values of Everzol ED reactive dyes for bamboo and conventional viscose fibers were determined. The tests of color matching using several combination dyes showed that the combination of dyes with approximately the same SERF values was suitable to be used for the trichromatic reactive dyes for the exhaustion dyeing of bamboo viscose fibers.(e) The adsorption of the reactive UV absorber on bamboo viscose fibers were greatly affected by temperature, Glauber's salt dosage and time while the adsorption dependence on soda ash dosage was less, and furthermore its adsorption sensitivity to Glauber's salt dosage was greater than that of reactive dyes. Both the finishing with the UV absorber and the dyeing with reactive dyes (especially chlorotriazinyl-containing dyes) provided good UV protection function for bamboo viscose fabrics. It was observed that the UV protection properties of reactive dyes had certain relevance to their adsorption intensity in the UV-B region. The UV absorber was not applicable to one-bath finishing and dyeing with the reactive dyes which were applied under medium or high temperature, but possible to be applied to the modified pre-adding alkali dyeing method.(f) Polycarboxylic acid incombination with the production of a reactive UV absorber and a low molecular weight chitosan was used as a multifunctional finishing agent for bamboo viscose fabric. After finishing, the wrinkle recovery angle of bamboo viscose fabric had a noticeable increase and the UPF values increased from 6 to 60.