The Preparation And Application Of Cationic Agent PECH-amine To Cellulosic Fibre With Low Molecular Weight And Moderate Nitrogen Content

For the purpose of environment protection and enhancing the dyeability of cellulosic fibres, one of cationic agents PECHl-amine3 to cellulosic fibre with molecular weight 672.4 and nitrogen content 5.75% was preparated. This paper studied the modifying craft to cellulosic fibre with PECHl-amine3, the dyeing craft of the cellulosic fibre after modify and the dyeing performance of modified cellulosic fibre, compared the dyeability of cellulosic fibre modified by cationic agents of different molecular weight, studied the application of cellulosic fibre modify by PECHl-amine3 on spelling dyeing with the dyestuff of red, yellow and blue, tested the physicial performance of the modified cellulosic fibre and the color fastness of the modified cellulosic fibre after being dyed.To further reduce the color difference because of the superficial modification, the author synthesized PECH1 with lower molecular weight from the internal structure of cellulose fiber. The conversion of PECH1 to PECHl-amine3 could be accomplished by adding dimethylamine at 95℃.The Flight Mass Spectrum, the Infrared Spectrum and the Ultimate Analysis show the molecular weight of PECH1 is 672.4 and the PECHl-amine3 contains 5.75% nitrogen.The pretreament process could be carried out by exhaust method. Cotton fabric would be pretreated using the exhaust method for 50 minutes at 95°C. The relationships between dye-uptake of pretreated cotton and alkali concentration and PECHl-amine3 concentration show the dye-uptake approached maximum values at 2g/l of sodium hydroxide and 7.5g/l of PECHl-amine3. The pretreatment is not suit for pad-dry method because it could not increase dye-uptake much.Cotton fabric, flax fabric, and viscose fibre were modified by PECHl-amine3 and then dyed by drict, reactive and deoxidize dye stufF(2%o.w.f). Results show that the dye-uptake of cotton fabric modified by PECHl-amine3 is 20~40% higher than that of not being modified, the K/S value of flax fabric modified by PECHl-amine3 is 50~500% higher than that of not being modified, the viscose fibre modified by PECHl-amine3 is 10~15% higher than that of not being modified.This paper also compared PECHl-amine3 and PECH4-aminel. The molecular weight of the PECH4-aminel is bigger than PECHl-amine3. Results show that the dye-uptake of the cellulosic fibres modified by PECHl-amine3 is almost equal to that of modified by PECH4-aminel,and the dye penetration is a little better.In order to father decreasing the dyeing difference of cellulosic fibres modified by PECHl-amine3 to anion dye, this paper also studied the dyeing characteristics of modified fibres. The experiment indicated that the half dyeing time is about 4 minutes. The dyeing difference is caused by that big speed of dyeing. Reducing the temperature of beginning dyeing, adding the penetrant JFC when dyeing would reduce colour difference. Joining JFC also would reduce the dye-uptake slightly. If the fabric was modified completely, dyeing with salt would heighten the dye-uptake;On the contrary, if the fabric was not modified completely, dyeing with salt would reduce the dye-uptake. Because salt did not play an important role in dyeing, the modified fabric should dye under no salt condition with an eye to environment-friendship and saving the cost.This paper also studied the application of PECHl-amine3 in spelling dyeing with red, yellow, blue three kinds of dye stuffs. Then tested the physical performance of modified fabric and the colour fastness of the dyed fabric. The experiment indicated that choosing the right dye stuffs which have similar affinity and blending value to cellulosic faber, the fabric modified by PECHl-amine3 could be dyed by spelling three colour. The physical force of the fabric modified by PECHl-amine3 was 71% to that of not being modified. It is permissional. The dry friction colour fastness of the modified cotton was nearly same to the non-modifiedcotton, while the wet friction colour fastness of the modified cotton was 0.5-1 lower than the non-modified cotton. But the wet friction colour fastness of the modified cotton is about 3-4 level, which is enough to meet the need of industrial production. The soap watering colour fastness of the modified and the non-modified cotton achieved the level of industrial production, about 4 level.Bagasse was modified by PECHl-amine3 and then was used to deal with the dyeing waste water. Results indicated that modified bagasse could absorb most of dye stuff in the dyeing waste water.