Cities Service Company

Saytech, Inc.

Lionel T Wolford

Anderson O Dotson, Jr

Francis T Wadsworth

Chien Yung Lee

(Cyclo)alkylenediammonium compounds corresponding to the formula: ##STR1## wherein X is halogen, R is an alkylene or cycloalkylene group containing 2-15 carbon atoms, each R' alone is an alkyl, cycloalkyl, or aralkyl group, and R'-R' together represent an alkylene, cycloalkylene, or aralkylene group are prepared by esterifying a tetrahalophthalic anhydride with a mono- or dihydroxyalkane, -cycloalkane, or -aralkane having a boiling point below 250.degree. C. to form a half-ester and then reacting the half-ester with a stoichiometric amount of a diaminoalkane or diaminocycloalkane containing 2-15 carbon atoms. The (cyclo)alkylenediammonium compounds of the invention are useful as flame retardants for normally flammable organic polymers and also have utility as intermediates for the preparation of N,N'-(cyclo)alkylene-bis-tetrahalophthalimides, which are also useful as flame retardants. The imides are prepared simply by heating the diammonium compounds.

Process for preparing nitrogen compounds

(Cyclo)alkylenediammonium compounds corresponding to the formula: ##STR1## wherein X is halogen, R is an alkylene or cycloalkylene group containing 2-15 carbon atoms, each R' alone is an alkyl, cycloalkyl, or aralkyl group, and R'---R' together represent an alkylene, cycloalkylene, or aralkylene group are prepared by esterifying a tetrahalophthalic anhydride with a mono- or dihydroxyalkane, -cycloalkane, or -aralkane having a boiling point below 250.degree. C. to form a half-ester and then reacting the half-ester with a stoichiometric amount of a diaminoalkane or diaminocycloalkane containing 2-15 carbon atoms. The (cyclo)alkylenediammonium compounds of the invention are useful as flame retardants for normally flammable organic polymers and also have utility as intermediates for the preparation of N,N'-(cyclo)alkylene-bis-tetrahalophthalimides, which are also useful as flame retardants. The imides are prepared simply by heating the diammonium compounds.

Salts of diamines and tetrahalophthalates

White N,N'-alkylene-bis-tetrabromophthalimides are prepared by reacting about two molar proportions of tetrabromophthalic anhydride with about one molar proportion of a diaminoalkane containing 2-6 carbon atoms in a solvent mixture having a boiling point of at least about 125.degree. C. and comprising about 50-97.5% by weight of a liquid aromatic hydrocarbon or halohydrocarbon having a boiling point of at least about 80.degree. C. and about 50-2.5% by weight of an alkanoic or aralkanoic acid having a dissociation constant not higher than about 6 .times. 10.sup.-5 at 25.degree. C. A preferred solvent is a mixture of about 70% by weight of xylenes and about 30% by weight of propionic acid having a boiling point of about 130.degree. C. The products are particularly useful as flame retardants.

Process for preparing bisimides and bisimides prepared thereby

(Cyclo)alkylenediammonium-bis-tetrahalophthalates corresponding to the formula: ##STR1## wherein X is halogen and R is an alkylene or cycloalkylene group containing 2-15 carbon atoms are prepared by hydrolyzing a tetrahalophthalic anhydride to the corresponding tetrahalophthalic acid and then reacting the tetrahalophthalic acid in the resultant reaction mixture with a diaminoalkane or diaminocycloalkane containing 2-15 carbon atoms in a molar ratio of about two molar proportions of the acid per molar proportion of the diamine. The (cyclo)alkylenediammonium-bis-tetrahalophthalates of the invention are useful as flame retardants for normally flammable organic polymers and also have utility as intermediates for the preparation of N,N'-(cyclo)alkylene-bis-tetrahalophthalimides, which are also useful as flame retardants. The imides are prepared simply by heating the salts until an acid number of substantially 0 is obtained.

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Freehold, NJ, United States of America

Lionel T Wolford