Preparation of UV-curable Waterborne Polythiourethane

doi:10.7517/issn.1674-0475.190522

Abstract

Abstract: A series of UV-curable waterborne polythiourethane dispersions were successfully prepared via sequential thiol-click reactions. Speciffically, thiol-isocyanate and thiol-Michael reactions were implemented, and the overall two-step procedure efficiently yielded desired product under mild reaction conditions. Initially, diisocyanate and excess dithiol were reacted to produce the oligomeric polythiourethane dithiol, which was afterwards selectively reacted with acrylate groups of glicerol-derived diacrylate-monomethacrylate monomer to provide the resin containing methacrylate functionalities along the polythiourethane backbone. After the resin was dispersed in water, what resulted in translucent emulsion, the UV-curable waterborne polythiourethane was obtained. As a significant amount of methacrylate groups were attached on the main polymer chains, a dramatical increase in the crosslink density of films was achieved after UV-curing. The resultant crosslinked materials exhibited excellent mechanical properties thus showing promise for coatings applications.

Key words: UV-curing, waterborne resin, thiol, thiourethane

XIE Han, ZHU Min. Preparation of UV-curable Waterborne Polythiourethane[J]. Imaging Science and Photochemistry, 2019, 37(6): 536-546.

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