Synthesis of a Reactive Cationic/Nonionic Waterborne Polyurethane Dye Fixative and Its Application Performance on Viscose Fiber Fabrics

A series of cationic waterborne polyurethane (CWPU) emulsions was synthesized with isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI) as hard segments; polyol (N210) and polyethylene glycol (PEG-2000) as soft segments; N-methyldiethanolamine (MDEA) as a hydrophilic chain extender; and trimethylolpropane (TMP) as a crosslinker. Then, the effects of the R-value, MDEA content, and TMP content on the properties of the CWPU emulsion, film, and fabric treatment were investigated. The results indicated that when the R-value was 3.0, the MEDA content accounted for 4.0% of the solid and the TMP content accounted for 1.0% of the solid. CWPU has excellent storage stability. Applying it to the fixing treatment of the viscose fiber fabrics can effectively improve the color fastness to rubbing, elasticity, surface smoothness, and anti-static properties.