Production of polyurethane foam with defined fire characteristics useful for making railway carriage equipment comprises reacting a polyether polyol with a diisocyanate in the presence of a graphite filler

摘要

Production of a cold-molded graphite-filled flexible polyurethane foam with a limiting oxygen index of 28% and a flame propagation velocity of 27 mm/second, with a nonpropagator fire classification and an F2 smoke classification, comprises reacting a polyether polyol with a diisocyanate in the presence of a graphite filler. Production of a cold-molded graphite-filled flexible polyurethane foam with a limiting oxygen index of 28% and a flame propagation velocity of 27 mm/second, with a nonpropagator fire classification and an F2 smoke classification, comprises reacting a polyether polyol of formula (I) with a diisocyanate of formula (II) in the presence of a graphite filler to form a polyurethane of formula (III): HO-R-OH (I) OCN-R'-NCO (II) (CO-NH-R'-NH-CO-O-R-O)n (III) (R, R' and n are not defined). An independent claim is also included for production of a cold-molded graphite-filled flexible polyurethane foam with a limiting oxygen index of at least 31% and a flame propagation velocity of 20 mm/second, with a nonpropagator fire classification and an F2 smoke classification, by reacting a diisocyanate of formula (IV) with water to form a polyurea diisocyanate of formula (V): OCN-R-NCO (IV) OCN-R-NH-CO-NH-R-NH-CO-NH-R-NCO (V) (R is not defined).