Preparation of a cured resole resin

In a method for the preparation of thermoset synthetic resinous resole bodies, the steps of the method comprising providing in intimate admixture (a) a resole resin, (b) a catalyst for the resole resin, the catalyst comprising a strong inorganic or organic acid, curing the mixture until the mixture has hardened to a self-supporting mass, the improvement which comprises

• including within said mixture a corrosion retarding agent consisting essentially of a particulate, inorganic, solid, acid-accepting material in at least a stoichiometric amount based on the catalyst, with the further limitation that when two parts by weight of the acid-accepting material are added with gentle stirring to 100 parts by weight of a solution of hydrochloric acid in deionized water, the solution having a pH of 1, at a temperature of 25.degree. C, the pH of the solution increases from about 0.1 to about 1 pH unit in 60 minutes, the particulate material having an acid-accepting value of from about 0.08 to 0.3 grams of hydrochloric acid as determined by dispersing one gram of an acid acceptor in 100 milliliters of 0.1 normal aqueous hydrochloric acid, the dispersion is agitated for 24 hours at a temperature of 25.degree. C and titrated with 0.1 normal aqueous sodium hydroxide to a pH of 7, the weight in grams of hydrochloric acid neutralized by the acid acceptor is then calculated and is the acid-accepting value, to thereby provide a cured resole resinous body having a reduced tendency to corrode steel.