SYNOPSISTwo-component polyurethane flame retardant coatings were prepared by blending 2,3dibromo modified polyesters (2,3-DBPOs) and polyisocyanate. 2,3-DBPOs were synthesized by polycondensation of 2,3-dibromopropanoic acid, a flame retardant aliphatic carboxylic acid, with 1,4-butanediol, trimethylolpropane, and adipic acid. The content of 2,3-dibromopropanoic acid was varied a t 10, 20, and 30 wt % for the polycondensation reaction. Various physical properties of these new flame retardant coatings were comparable to nonflame-retardant coatings. They showed desirable properties for a flame retardant coating such as rapid drying and 9-12 h of pot life. Coatings with 30 wt % 2,3-dibromopropanoic acid did not burn using the vertical burning test. 0 1996 John Wiley & Sons, Inc.