The Impact On Dyeing With Sulfur Dyes With The Use Of Pech-amine

PECH-amine is one of the cationic modification agents which come from the reaction of dimethylamine and polymer of epichlorohydrin under the condition of 95℃. Currently there are many researches about the PECH-amine, but they are mainly about the modification of cotton or other cellulose fibers with PECH-amine and also the dyeing performance of modified fabric on reactive or direct dyes. Based on this achievement, this paper studied how the different types and amount of solvent impact on the synthesis of PECH-amine. And for the first time discuss the impact on the dyeing process of cotton fabric with sulfer dyes by the use of PECH-amine.The mainly contents of this paper include:synthesis of PECH-amine, cationic modification of cotton fabrics by PECH-amine and the dyeing perfomance of sulfer dyes on modified cotton fabrics, fixation process of cotton sulfer dyings with PECH-amine.Carbon tetrachloride (CCl4) is a solvent for polymerization of epichlorohydrin, but it is toxic, amost the greatest toxic of chlorinated methane. So it is limited, even it may be disabled in the future. For this reason, this paper trys to use less amount of CCl4 or replace CCl4 by other solvents for the synthesis of PECH-amine. The research shows that cyclohexane can be used as the solvent of this polymerization. The test of viscosity proves that the molecular weight of PECH decreases gradually with the reducing amount of CCl4 from 100mL to 25mL. Compared with PECH that use CCl4 as solvent, the molecular weight of PECH4 which use cyclohexane as solvent is less.The synthesised PECH3-aminel using CCl4 as solvent, which has low molecular weight and moderate nitrogen content, can significantly increase the K/S value of modified cotton fabrics for sulfer dying. At the same time, the dyeing levelness is relatively good. Factors to the dyeing performance of modified cotton fabrics for sulfer dying like the PECH3-aminel concentration, NaOH concentration and different kinds of methods have been studied. The results showed that the optimum exhaust process is PECH3-aminel 1g/L and NaOH 1g/L; and the optimum padding process is PECH3-aminel 8g/L, NaOH 8g/L and the rollers pressure 1kg/cm2. At the same time it shows that the K/S vlaue of sulfer dyed (5% o.w.f.) cotton fabrics modified by PECH3-aminel can be improved greatly and the dyeing rate also increases. But the dyeing levelness of modified fabrics is slightly lower and the colour is somewhat volatile. Further studies are needed to solve these problems. In a word, modification of cellulosic fibers plays an importment role in reducing energy consumption, improving efficiency, saving dyes and protecting environment.The synthesied PECH1-amine2 using CCl4 as solvent, whose molecular weight is high and water-soluble is well, can be used as fixing agent for cotton sulfer dyeings, which can improve its wet rubbing fastness effectually. Factors exerting influence on the finishing results are discussed, such as fixing methods, dosages of PECH1-amine2 and NaOH, as well as the rollers pressure. The results showed that the optimum exhaust process is PECH1-amine2 2g/L and NaOH 8g/L; and the optimum padding process is PECH1-amine2 32g/L, NaOH 8g/L, rollers pressure 1kg/cm2 and curing temperature 100℃. It also proves that the fixing effect of the exhaust method is better than that of the padding method. By exhaust process, the wet rubbing fastness of the fixed cotton sulfur dyeings (15% o.w.f.) can be enhanced by 0.5 to 1.5. For the Sulfur light green 7713, it can be enhanced by about 1.5. And for the Sulphur black BR, it can be enhanced by about 1. Meanwhile, the levels of the soaping fastness of the fixed cotton sulfur dyeings were increased by 0.5 to 1.