Study On Dyeing Properties Of Sisal Fiber With Reactive Dyes

Sisal fiber has many excellent properties,such as tough texture,friction resistance and corrosion resistance,cheap and easy to obtain,and can be naturally degraded,etc.,which is especially widely used in industry,agriculture and national defense fields.In recent years,sisal fiber,as a kind of plant fiber,has attracted more and more attention to environmental protection and ecological problems.However,sisal fiber has poor dyeing performance due to its close molecular structure arrangement,which seriously restricts the wide application of sisal fiber and its fabric in the textile field.In order to have a better understanding of the dyeing properties of sisal fiber,this paper selected the cibacron series of reactive dyes for dyeing,color matching and other aspects of research,including the following three aspects:(1)Firstly,the dyeing mechanism of sisal fibers dyed with reactive dyes was studied by means of dyeing kinetics and dyeing thermodynamics.The dyeing process characteristics of the three dyes were analyzed according to the dyeing rate curves.The dyeing percentage of cibacron red was higher than that of the other two dyes at the same temperature.Under the condition of temperature rising to 70? and 80?,the dyeing situation of cibacron yellow and cibacron blue was close.According to the calculation of dyeing kinetics parameters,it is found that the diffusion coefficient increases and the half-dyeing time decreases with the increase of temperature.The thermodynamic analysis shows that the three dyes accord with Langmuir type curves.(2)The effects of three different dyeing processes on the properties of sisal fiber were investigated by taking dyeing depth and color fixation rate as indexes.It was found that the color depth and color fixation rate of sisal fiber were better by one-bath two-step dyeing and alkali pretreatment than by one-bath one-step dyeing.In addition,under the condition of the same dyeing depth,the amount of dyes used by one-bath two-step method and pre-alkali adding process were compared.Compared with the one-bath two-step method,the dye saving rate of Cibacron red,yellow and blue in pre-alkali adding process reached 36.10%,33.33% and 34.64%.Then to accelerating agent, fixing agent dosage,the dosage of dyeing temperature,dyeing time four single factor on the dyeing performance was analyzed,and the further design of the four factors three levels orthogonal experiment,the optimal dyeing process conditions were determined: accelerating agent dosage of 30 g/L,dyeing temperature is 80 ?,dyeing time for 60 min,the dosage of the fixing agent for 20 g/L.It was found that under the optimal dyeing process,the dyed fibers had bright color and good dyeing condition,and the horizontal lines and vertical joints on the fiber surface were not obvious.By comparing the mechanical properties,it is found that the breaking strength of the fiber decreases by 12.44%,the elongation at break increases by 9.09% and the initial modulus decreases by 8.04%.(3)By means of dyeing rate curve,dyeing characteristic parameters and other ways to explore the compatibility.It was found that the dyeing rates of the single dyes were similar,and the affinity differences of the dyes were small.In addition,through the calculation of S,E,F,R dyeing characteristic parameters,the difference between the three dyes dyeing characteristic values is less than 15%,in line with the requirements of color matching.Secondly,cibacron red/yellow,cibacron red/blue,cibacron yellow/blue two-component color system and cibacron red/yellow/blue threecomponent color system were established.The dyeing rate of cibacron red dye in the two-component system and the three-component system was almost unchanged,which could maintain a good independence.The dyeing rate of cibacron yellow and cibacron blue was different among the three components.Finally,the fiber was dyed in different combination ways,and compared with the conventional dyeing process and the prealkali adding process,it was found that the process with matching color was ideal and could be used in practical production.