Study On The Synthesis And Dyeing Properties Of Dyes Containing Aromatic Primary Amine With Bridge Group

Among the dyes commonly used for silk dyeing at present,acid dyes have bright colors but poor color fastness to wet treatment.Although reactive dyes can be bonded with silk by covalent bond to obtain high color fastness to washing and friction,they need to be fixed under high temperature and alkaline conditions,which is easy to lead to fiber damage.At the same time,there are also problems such as large amount of salt and low utilization rate of dyes.Therefore,it is of great significance to develop a dye type with high color fastness,energy saving and environmental protection and its application technology for the sustainable development of high-quality silk products.On the basis of previous work,this research group proposed an aromatic primary amine dye Mannich reaction dyeing method,which can obtain higher color depth value under low temperature acidic conditions,and has ideal color fastness to soap washing and friction.However,there are few available dyes,and the fast performance of dyed fabrics is not ideal.Therefore,this paper further carried out the design and synthesis of arylamine dyes and the study on the dyeing and printing properties of silk fabrics.In particular,after printing silk fabrics with arylamine dyes,the color fixing properties of silk fabrics can be achieved through low temperature moisturizing and Mannich reaction,so as to achieve the purpose of low temperature alkaline-free and high color fastness printing,and provide a new way for the development of energy saving and environmental protection printing method of silk fabrics.In order to improve the light fastness of aromatic primary amine dyes,4chloromethyl triazine commercial reactive dyes with good light fastness were modified,and the reactivity of Cl atoms on the original active groups was used for arylamination,so that the original triazine structure was transformed into a bridge group between the dye hair color parent and the aromatic primary amine group,so as to obtain the arylamine dye containing the bridge group.In the Mannich reaction between arylamine dye and silk,the parent properties of the original dye remained unchanged.Through the experimental study on the dyeing properties of silk fabrics by the traditional reactive dye dyeing method of modified precursor dyes and the modified Mannich reaction dyeing method with different aldehyde components,it was found that the synthetic silk fabrics with bridge aryl-primary amine dyes dyed by Mannich reaction were compared with the silk fabrics without modification and dyed by conventional reactive dye method.Mannich reaction dyeing of silk fabrics with benzyl arylprimary amine dyes using formaldehyde as aldehyde component has higher dyeing rate and color depth value.On this basis,the formaldehyde/acetone aldehyde Mannich reaction dyeing process conditions were optimized for arylamine dyes containing bridge base.After the optimization,the color depth value and relative color fixation rate of the two kinds of Mannich reaction dyeing processes were improved.The dyeing rate of each dye could reach more than 90%,and the color fastness to washing and rubbing could reach grade 4or above.Compared with the original reactive dyes,the fast performance did not decrease significantly,and the breaking strength loss rate was reduced by about 6%～9%compared with conventional reactive dyes.Through the above modification method,not only can the ideal fast performance of aromatic primary amine dye be obtained,but also can enrich the chromatographic performance of aromatic primary amine dye.Then,a study of low temperature moisturizing Mannich reaction color fixation was carried out on the printing of silk fabric with modified synthetic arylamine dyes.The traditional reactive dye formula and the three-component Mannich reaction formula of arylamine dyes were used to carry out screen printing on silk fabric,and the coloring properties of the two dyes and printing formula were compared.And compared with conventional high temperature steam fixation.The results showed that the color depth values of aromatic amine dye printing and conventional reactive dye printing based on Mannich reaction mechanism were similar under the same low temperature moisturizing conditions,and the two printing methods could obtain the color depth values close to the conventional reactive dye high temperature steam color fixation process when the two printing methods were moisturizing at 60℃ for 3 h.The color fastness to soap and friction of the two printing methods can reach class 4 or above,and compared with the traditional reactive dye printing high temperature steam method,the breaking strength of the modified aromatic primary amine dye printing with bridge base is improved by Mannich reaction low temperature color fixing method,and there is little difference in the fast performance of the two.In summary,by modifying the traditional reactive dyes,four arylamine dyes containing bridge base were synthesized.The modified dyes could obtain higher color depth value by dyeing silk fabrics with Mannich reaction,and the properties of color fixation rate,fastness to sunlight,color fastness to washing and friction were satisfactory.This study can provide theoretical basis for exploring new methods of energy saving and environmental protection printing and dyeing of silk fabrics.