Intumescent fire retardant compositions containing pentaerythritol cyclic diphosphates

摘要

Intumescent coating compositions comprising a coating vehicle and a non-flaming intumescent agent of the formula ##STR1## wherein both X's are identical and selected from the group comprising oxygen and sulfur and wherein each Y is independently selected from the group consisting of alkoxy, halogenated alkoxy, cycloalkoxy, halogenated cycloalkoxy, olefinicoxy, halogenated olefinicoxy and --NR.sub.2 groups, wherein each R is independently selected from the group consisting of hydrogen, alkyl, halogenated alkyl, olefinic, and halogenated olefinic groups, said alkoxy, cycloalkoxy, olefinicoxy, alkyl and olefinic groups containing from 1 to about 12 carbon atoms and said halogenated groups containing from 1 to about 6 halogen substituents per group. A method for protecting a substrate from heat and fire comprising applying to the substrate an intumescing amount of the above described intumescent agents.