Aromatic Primary Amine Acid Dyes Dyeing Protein Fibers Base On Mannich Reaction And Structure-activity Relationship

Silk is delicate texture, soft and breathable, wool is soft and elastic, warm and comfortable.they are the most commonly used protein fiber in daily life. At present, protein fiber can be dyed by acid dyes, reactive dyes and metal complex dyes. However, the color fastness of dyed fabric dyed by acid dyes is poor; reactive dyes are easy to be hydrolyzed in the process of color fixing,and produce a large number of non ferrous wastewater. Therefore, to explore a new method for the dyeing of protein fiber with environment friendly and good color fastnessis important for the green development of dyeing industry.In this paper, for the problem of protein fiber dyeing, we select, design and synthesis acid dyes with aromatic primary amine structure, by Mannich reaction principle, through the bridging effect of aldehydes, to realize electrophilic substitution reaction for tyrosine residues in protein fibers, form a covalent bond between the dye and protein fibers, so as to enhance the wet fastness of the dyed fiber.First of all, choose 3 commercial acid dyes(C.I.acid black 1, C.I.acid green 20, C.I.acid brown 4) containing the structure of the aromatic amine, the use of Mannich reaction dye silk and wool fiber, and further studied the combination of dyes and fibers. The study showed that the Mannich reaction method, C.I.acid green 20 and C.I.acid brown 4 can be used to dye protein fiber, and the formation of covalent bond, it is proved that the method of Mannich reaction of protein fiber is feasible. Secondly, design, synthesis 12 aniline and naphthylamine type acid dye,systematic study the structure-activity relationship betweendye structureand Mannich reaction staining effect.By comparing the color depth and color fastness of silk dyed with different dyes,it is found that the structure of the structure containing aromatic amine groups, amino acid and hydrogen bond is not easy to form intramolecular hydrogen bonds, water-soluble dyes suitable for protein fiber Mannich reaction, can obtain a higher dye color depth and color fastness. The dye D2, D3, R3, γ1 dyes silk by the Mannich reaction, the color fastness to washing resistance were in grade 3 or more, rubbing fastness reached 4-5.