Design and Preparation of Tertiary Amine Modified Polyurethane Acrylate Oligomer with Co‐Initiation/Polymerization Bifunctions for Photo‐Curable Inkjet Printing of Textiles

Abstract In order to resolve the conflict issues existing in currently available polyurethane acrylate (PUA) oligomers for photo‐curable inkjet printing of textile, and to avoid the safety problems caused by the immigration of small molecule amine co‐initiator, a series of tertiary amine modified PUA oligomers are delicately designed and synthesized. The chemical structures of the synthesized PUA oligomers are confirmed by FTIR and 1H‐NMR analyses. The optimized PUA oligomer/hydroxyethyl acrylate based polymerization system show a low viscosity, high storage stability and good compatibility with various functional segments. Furthermore, the modified PUA oligomer acts as both the photopolymerization constituent and the macromolecular co‐initiator assisting to achieve high photopolymerization rate and conversion rate, and avoiding the disadvantages caused by the migration of small amine co‐initiators. Benefitting from the semi‐IPN formed by this polymerization system with suitable crosslinking density and phase separation degree, a soft, strong and flexible cured film is obtained. The high photo‐reactivity with low viscosity of the polymerization system and the good flexibility with high strength of the resultant photo‐cured film ensures the applications of the modified PUA oligomer, and the printed fabrics achieve 4 grade of colorfastness with improved handle properties, as well as brilliant color and fine patterns.