The Synthesis And Application Of Cationic Polyurethane Fixing Agent

Ever since, although the direct dyes and reactive dyes have wide application, the washing,soaping and rubbing fastness of the fabrics dyed with which is still relatively poor, especially thewet rubbing fastness of which is hard to reach the3level, so the fabric dyed with direct dyes andthe deep color fabric dyed with reactive dyes generally need fixing processing.Polyamine fixing agent is a kind of cationic fixing agent, containing cationic groups whichcan combine anionic dyes (as direct dyes, reactive dyes and acid dyes) with ionic bond. Meanwhile,the fixing agent molecular also contains reactive group, which will react with the fibres in the highbaking temperature. Through these two kinds of force combination, the dyes combines inside thefibers more tightly.Polyamine fixing agent was mainly polymerizated with organic amines and epichlorohydrin.One kind of efficient formaldehyde-free fixing agents to cotton fabric was synthesizedwith epichlorohydrin, dimethylamine, triethylamine, diethylene triamine, triethylenetetraamine, tetraethylene pentamine and tetraethylene pentamine in the topic. Through aseries of screening of raw materials, the best raw materials combination reaction was determined:adding tetraethylene pentamine and epichlorohydrin, then adding triethylamine for reaction.The best synthesis process: reacting f tetraethylene pentamine with epichlorohydrin in coldwater for1h, and then adding triethylamine,reacting at60℃for5h, The molar ratio oftetraethylene pentamine to epichlorohydrin to triethylamine to was1:6:1.5.The polyaminefixing agent is a pale moderate viscosity, homogeneous, stable, yellow liquid. The solid content is44.3%, and the centrifugal stability is good.The self-made polyamine fixing agent was analyzedby infrared spectrum characterization.The optimized padding application of technology of polyamine fixing agent was: dyedcotton fabricsâ†'two dip two rolling (dosage of the fixing agent is60g/L, rolling over rateis80%, and pH is10)â†'drying(70℃,3min)â†'baking (130℃,3min).After it was applied tocotton fabrics dyed with reactive dyes, the washing fastness increased from4level to4~5level, dry rubbing fastness increased from4level to4~5level, wet rubbing fastnessincreased from2level to3level, washing fastness increased from2level to3~4level. When it was applied to cotton fabrics dyed with direct dyes, dry rubbing fastness increasedfrom4level to4~5level, washing fastness increased from2level to3~4level.The effectenhance remarkable. The optimized impregnation application of technology of polyaminefixing agent was: dyed cotton fabricsâ†'immersed in liquid (the fixing agent dosage was3%(o.w.f.), bath ratio is20:1,60℃,30min),â†'drying(70℃,3min)â†'baking (130℃,3min).After it was applied to cotton fabrics dyed with reactive dyes, the washing fastnessincreased from4level to4~5level, dry rubbing fastness increased from4level to4~5level, wet rubbing fastness increased from2level to3level, washing fastness increasedfrom2level to3~4level. When it was applied to cotton fabrics dyed with direct dyes, dryrubbing fastness increased from4level to4~5level, washing fastness increased from2level to3~4level. This synthesized fixing agent is more obvious for wet rubbing fastnessreactive dyes and wet rubbing and washing fastness of fabric dyed of direct dyes.It has a goodapplication prospect.