Design, Synthesis And Application Of Styrylpyridinium Hemicyanine Fluorenscent Dyes

In our research group’s previous studies, styrylpyridinium hemicyanine fluorenscent dyes were employed as cationic dyes in dyeing acrylic and cationic dyeable polyester(CDP) to prepare fluorescent fabrics. On the purpose of ensuring styrylpyridinium salts forming covalent bonds with natural fibers such as cotton, silk, wool and achieving good dyeing properties and fluorescence properties simultaneously, the styrylpyridinium salt molecular structures were reasonable designed and dyeing methods were improved. Styrylpyridinium hemicyanine fluorenscent dyes suitable for natural fibers such as cotton, silk, wool were developed, in order to expand styrylpyridinium salts’ scope of application in the field of textile.The two innovative ideas of dyestuff structure designing are described as follow:1. Styrylpyridinium cationic reactive dyes such as Dye 1and Dye 2 with integrated structures of styrylpyridinium salt and reactive dye were designed.2. Styrylpyridinium crosslinking dyes such as Dye 3, DHEASPBr-C2, Polymeric dye 1and Polymeric dye 2 with integrated structures of styrylpyridinium salt and crosslingking dye were designed.The structures and properties of 5 new dyes( Dye 1、Dye 2、Dye 3、Polymeric dye 1 and Polymeric dye 2) were characterized by infrared spectroscopy, nuclear magnetic resonance hydrogen spectrum, mass spectrometry, high resolution mass spectrometry, ultraviolet absorption curve spectrophotometry, fluorescence emission curve, Stokes shift,fluorescence lifetime.The main innovations of the dyeing methods are described as follow:1. Compared with ordinary reactive dyes, Dye 1 and Dye 2 have cationic soluble groups, and Dye 2 has α-bromo acrylamide reactive group which can fix with fibers in alkali free and high temperature condition. Therefore, Dye 1 can dye silk under the condition of salt free, Dye 2 can dye wool under the condition of salt free and alkali free, which is advantageous to the cleaner production and environmental protection.2. Dye 2 can dye acrylic following cationic dyeing process, and also dye wool following reactive dyeing process. Therefore, Dye 3 can realize dyeing wool/acrylic blends in one bath using a single dye.3. Under property technological conditions, crosslinking dyeing and anti-wrinkle finishing process can be combined in one step, when cotton is dyed with DHEASPBr-C2, using polymaleic acid as crosslinking agent and sodium hypophosphite as the catalyst,Dye 1 and Dye 2 have reactive groups(dichloro triazine and α-bromo acrylamide) and can be employed in dyeing silk and cotton following exhaust dyeing method of reactive dyes. Dye 3、DHEASPBr-C2、Polymeric dye 1and Polymeric dye 2 have active groups(amino and hydroxyl) and can be employed in dyeing cotton and silk following crosslinking dyeing method. All dyes were firmly linked to fibers through covalent bonds. The high exhaustion, fixation and color fastness indicating the dyeing performance of these dyes is good. Good fluorescent properties of the fabrics and yarns dyed by the styrylpyridinium hemicyanine fluorenscent dyes which were researched in this paper were illustrated with photographs under UV lamp, reflectance curves, fluorescence emission curves and chromaticity coordinates. It is worth mentioning, under property dye concentrations, the cotton dyed by DHEASPBr-C2 meets the requirements of fluorescent orange of EN 471-2003, whereas, the silk dyed by Dye 1 and wool/acrylic blend dyed by Dye 2 meet the requirements of fluorescent pink of EN-1150-1999.