Design of hybrid nonisocyanate polyurethane coatings for advanced ambient temperature curing applications

摘要

This study is focused on development of environmentally benign, two component, high solid, nonisocyanate Polyurethane (NIPU) coatings through a novel route based on cyclic carbonate/amine chemistry. Cyclic carbonates are synthesized and reacted with an excess amount of amine to yield polyurethane polyamines (PUPAs). Coatings are then prepared by using stoichiometric proportions of PUPAs and aliphatic epoxies as crosslinkers and their coating properties are studied. Results reveal that by proper design of NIPU oligomers-functional group content, backbone structure, and molecular weight (M-n)-coatings with outstanding performance features such as low temperature flexibility and resistance to chemicals can be obtained and selected coatings containing PUPA with M-n = 1480 and 1:1.5 mol ratio of low-molecular-weight amine exceed the performance of a conventional isocyanate-based reference sample. Elimination of isocyanates, substantially reduced volatile organic compounds as well as fast ambient curing, make these polyurethane coatings a promising alternative for various industrial applications. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47266.