Study On Low-temperature Dyeing Technology Of Acrylic/Wool Blends

Acrylic yarn, wool yarn and acrylic/wool yarn were widely used in sweater yarn manufacture, but the traditional boiling-dyeing method of these materials have many disadvantages, such as high energy consumption, huge amount waste emission, large dosage of leveling agent and serious damage of the fiber due to high dyeing temperature. So it is necessary to develop a kind of environmental friendly technique of dyeing acrylic yarn, wool yarn and their blends at lower temperature. And using low-temperature dyeing accelerants is one of a convenient, effective and energy-efficient dyeing technique to achieve the aim. Therefore the research on technique of dyeing acrylic fiber or wool fiber at low temperature not only has theoretical value, but also provides practical application value for manufacture.The low temperature dyeing accelerants that could adjust and control the structure of acrylic fiber during dyeing were developed, and then the affections of accelerants on the structure and properties of acrylic fiber were researched. Furthermore, the influence of low temperature dyeing accelerants on the dyeing mechanism of acrylic fiber dyed with cationic dyes was analyzed through studying dyeing kinetics and thermodynamics. The optimum dyeing process of acrylic fabric dyed with cationic dyes at 85 ?C was obtained based on the single factor method and orthogonal tests. The compatibility among of cationic dyes, Lanaset dyes and auxiliaries that existed in one dyeing bath were investigated. Moreover, the research of staining of wool fabric with cationic dyes was emphasized, and then a dyeing process of improving the staining of cationic dyes on wool fabric at 85 ?C was obtained. Finally, a dyeing process of union dyeing for a red color on acrylic/wool blends in one bath was developed based on the above researches.First, three kinds of accelerant were developed as the low temperature dyeing accelerants of acrylic fiber dyed with cationic dyes, the influence of these accelerants on the structure and properties of acrylic fiber had been analyzed through various tests like fineness, SEM, breaking strength, CDT, XRD and FITR. The results showed that these three kinds of accelerant had no influence on the chemical composition and crystal type of acrylic fiber, though all of them could decrease the quasi-crystallinity of acrylic fiber, and also have a certain swelling for acrylic fiber, furthermore, all of the accelerants could increase the breaking strength of acrylic yarn, all the acrylic yarn was treated by simulating its dyeing.The kinetics and thermodynamics of acrylic yarn dyed with Cationic Turquoise Blue X-GB was investigated. The results indicated that the three kinds of accelerant could heighten the diffusion coefficients, equilibrium dye-uptake and dyeing rate constants of cationic dyes on acrylic fiber effectively, meanwhile, shorten half-dyeing time significantly. Furthermore, the partition coefficient, standard affinity and dye saturation value also increased by using the accelerants. Benzyl alcohol was one of the accelerants had the best effect on improving dye-uptake of acrylic yarn dyed with cationic dyes at 85℃, while accelerantШalso could realize the aim basically.The optimum dyeing process of acrylic fabrics dyed with cationic dyes at 85 ?C was obtained by single factor method and orthogonal tests. The dyeing temperature, dyeing time, pH value, liquor ratio, the dosage of leveling agent 1227 and accelerantШwere 85?C, 60min, 4.5-5.0, 1:20, 0.03-0.04 mL/g (acrylic) and 1.25-1.5 mL/g (acrylic), respectively. The washing color fastness and rubbing fastness of acrylic fabric applicated this optimum dyeing process were higher than the results of without accelerant, and could reach the level of traditional boiling dyeing basically. When acrylic/wool blends were dyeing in one bath, the interactions among of cationic dyes, Lanaset dyes and auxiliaries may be very complicated. The results indicated that cationic dyes and Lanaset dyes and all of the auxiliaries in the bath had a good compatibility at 85℃when the pH value was 4.5-5.0.The staining of acrylic/wool blends in one dyeing bath at 85℃was studied in this paper. The results showed that the staining of Lanaset dyes on acrylic fiber was little, however, cationic dyes especially Cationic Turquoise Blue X-GB had a serious staining on wool fabric. Furthermore, we got a dyeing process through discussing the effect of factors such as dyeing temperature, pH value, dyeing time and accelerantШon the staining of cationic dyes on wool, which could improve the staining of cationic dyes on wool well. Based on the above researches, a dyeing process of union dyeing for a red color on acrylic/wool blends in one bath had been developed by color matching.