Composition comprising epoxy resin and cationic amine phosphonium catalyst

#The present invention pertains to catalysts for the reaction of reactive hydrogen-containing compounds or acid anhydrides, particularly phenolic hydroxyl- and carboxyl-containing compounds with epoxides, compositions containing such catalysts, to processes employing such catalysts and curable and cured products or articles.

#High molecular weight epoxy resins have been previously prepared by reacting phenolic compounds with epoxide compounds in the presence of such catalysts as inorganic bases, amines, ammonium salts, phosphine and phosphonium salts such as described in U.S. Pat. Nos. 3,284,212; 3,547,881; 3,477,990; 3,948,855 and 4,438,254. However, most of these catalysts while being suitable for catalyzing the reaction between phenolic hydroxyl-containing compounds and epoxides, most of these catalysts possess some undesirable feature such as poor reactivity which requires high catalyst levels and long reaction times; poor selectivity to the reaction of phenolic hydroxyl groups with epoxides, difficulty in deactivation and the like.

#In a continuous process for the production of advanced epoxy resins such as by the extruder process disclosed in U.S. Pat. No. 4,612,156 it would be highly desirable to have available for use in that process a catalyst which would be highly active, highly selective to phenolic hydroxyl groups, and easily deactivated.

#In the process of the present invention, the reactants are reacted together in the presence of the catalyst at any suitable temperature and pressure for a length of time sufficient to advance the resin to the desired molecular weight. Particularly suitable temperatures are from about 50.degree. C. to about 280.degree. C., more suitably from about 100.degree. C. to about 240.degree. C., most suitably from about 120.degree. C. to about 220.degree. C. Suitable pressures include atmospheric, subatmospheric and superatmospheric pressures. Particularly suitable pressures are those from about 1 psig (6.9 kPa) to about 150 psig (1,034.2 kPa), more suitably from about 5 psig (34.5 kPa) to about 80 psig (551,6 kPa), most suitably from about 10 psig (68.9 kPa) to about 20 psig (137.9 kPa). The time depends upon the particular catalyst and reactants employed as well as to the degree of advancement desired; however, particularly suitable reaction times include from about 0.5 to about 20, more suitably from about 1 to about 8, most suitably from about 2 to about 5 hours.

#Suitable such catalysts which can be employed herein include those represented by the following formula ##STR1## wherein each R is independently hydrogen, a monovalent hydrocarbyl group, a halogen, preferably bromine or chlorine, nitro or --C.tbd.N or OH or alkyl or alkoxy or halogen substituted hydrocarbyl group having from 1 to about 20, more preferably from 1 to about 10, most preferably from 1 to about 6, carbon atoms, or a R" group; R' is a divalent hydrocarbyl group having from 1 to about 20, more preferably from 1 to about 10, most preferably from 1 to about 5, carbon atoms; each R" is independently hydrogen or a monovalent hydrocarbyl group having from 1 to about 20, more preferably from 1 to about 10, most preferably from 1 to about 5, carbon atoms or a halogen, preferably bromine or chlorine, nitro, --C.tbd.N, or --OH substituted hydrocarbyl group having from 1 to about 20, more preferably from 1 to about 10, most preferably from 1 to about 5, carbon atoms; and Z is any suitable anion.

#The term "hydrocarbyl" as employed herein means any aliphatic, cycloaliphatic, aromatic, aryl substituted aliphatic or cycloaliphatic, or aliphatic or cycloaliphatic substituted aromatic groups. The aliphatic groups can be saturated or unsaturated.