description the invented compounds may be formed by the reaction of a monoether of a poly alkylene glycol optionally in combination with the phenol halophenol or c 1 20 aliphatic or halogenated aliphatic monohydroxyl compounds with phosphorus pentoxide alternatively the monohydroxyl compounds may be reacted in sequence remnant acid functionality is assured by reacting a stoichiometrically limited amount of the monohydroxyl compound preferably in order to assure the presence of at least some poly alkylene glycol monoether remnant in each molecule of the reaction product at least one quarter mole of poly alkylene glycol monoether is reacted with each mole of p 2 o 5 the reaction technique is well known being similar to that disclosed in u s pat no 2 866 680 accordingly the monohydroxyl reactant is controllably added to a slurry comprising phosphorus pentoxide and an organic solvent such as the lower alkanes aromatics or halogenated hydrocarbons a preferred solvent is dichloromethane to compensate for possible water contamination of the monohydroxyl reactant excess p 2 o 5 is preferably utilized the ratio of monohydroxyl compound remnant to phosphorus in the reaction product is desirably about 1 1 the exothermic reaction causes heating of the reaction mass proper choice of a solvent allows the reaction to be maintained at a gentle reflux at moderately elevated temperatures less than about 150 u00b0 c the reaction may be continued for several hours or longer until the p 2 o 5 is substantially completely reacted additional heating during the course of the reaction may be accomplished by conventional means the product generally a light colored liquid may be separated from any excess unreacted p 2 o 5 by decanting or filtration and the solvent removed if desired by.