Investigation Of The Cotton Fabric Pretreatment Processes Using Enzyme

In this thesis, cotton fabric pretreatment by using a series of enzymes were reviewed. The present situation and development of enzymes and their using technologies were also investigated. The principles of the enzymes,the factors of the enzyme activation were discussed. The structure and chemical composition of the cotton were involved. Two cotton fabric pretreatment technologies were studied amply here. The suitable cotton fabric pretreatment technologies were obtained by means of measuring some fabric properties such as desizing ratio, capillarity, whiteness, and strength. Hydrolytic kinetics of starch on the cotton fabric under the action of amylase through cold pad-batch were also discussed.When the dwelling temperature is 20℃, the suitable cotton fabric pretreatment technology under the process of enzymatic cold pad-batch is: immerged with solution ( amylase 0.1%owf, pectase 0.1%owf, JFC 1g/L,pH 8 )→two dipping and rolling of pick-up 100%→dwelling for 6 hours→shaking at constant temperature of 95℃for 30min ( sodium dodecyl benzene sulfonate 3g/L, sodium carbonate 5g/L, hydrogen peroxide 5g/L, sodium silicate 1g/L)→washing.When the dwelling temperature is 35℃, the suitable cotton fabric pretreatment technology under the process of enzymatic cold pad-batch is: immerged with solution ( amylase 0.1%owf, pectase 0.1%owf, JFC 1g/L,pH 8 )→two dipping and rolling of pick-up 100%→dwelling for 4 hours→shaking at constant temperature of 95℃for 30min ( sodium dodecyl benzene sulfonate 3g/L, sodium carbonate 5g/L, hydrogen peroxide 5g/L, sodium silicate 1g/L )→washing. Washing and bleaching were combined into one step in these two pretreatment technologies.The suitable cotton fabric pretreatment technology under the high temperature steaming is: immerged with solution ( amylase 0.1%owf, pectase 0.1%owf, JFC 1g/L,pH 8 )→two dipping and rolling of pick-up 100%→steaming at 100℃for 3min→shaking at constant temperature of 95℃for 30min ( sodium dodecyl benzene sulfonate 3g/L, sodium carbonate 5g/L, hydrogen peroxide 5g/L, sodium silicate 1g/L )→washing. This pretreatment technology has the advantage of short time,less procedure,easy operation,better effects.The influences of amylase concentration and batching time on desizing ratio under different temperature were investigated, and hydrolytic kinetics of starch on the cotton fabric under the action of amylase were also discussed, which showed that the initial reaction followed first order kinetics. When concentration of amylase was 0.1%owf, activation energy of 26KJ/mol was obtained, which demonstrated that hydrolytic rate of starch increased rapidly with the increase of temperature.