Abstract: A phenolic resole resin for use as a foundry binder which has been internally modified to reduce its hot strength and thereby enhance its shakeout property is disclosed. The resin is the reaction product of a phenolic compound; a dialdehyde; and formaldehyde. A process of preparing such resin is also disclosed, comprising first reacting the phenolic compound and the dialdehyde, and subsequently reacting the product with the formaldehyde. The resin may be, in a preferred embodiment, an ester-curable alkaline phenolic resin. Also disclosed are a raw batch formulation including the resin of the invention, and foundry articles prepared therefrom.

Abstract: There are disclosed methods and compositions for retarding the ambient temperature hardening of a phenolic resole resin alone or with an aggregate when such resin is contacted with a nitroalkane and a hardening agent such as lightburned magnesium oxide, an organic ester functional hardening agent, and mixtures of lightburned magnesium oxide and an organic ester functional hardening agent in an alkaline medium. There is also disclosed a hardener composition for phenolic resole resins wherein the hardener composition consists essentially of a solution of a nitroalkane in an organic ester functional hardening agent.

Abstract: The present invention provides methods for treating reclaimed sand obtained from dismantled foundry molds and cores which contain residue from a cured binder of an ester-cured alkaline phenolic resin. Treatment of the reclaimed sand with a silane solution containing one or more amines, particularly an aqueous solution containing a silane and one or more amines, enhances the tensile strengths of foundry molds and cores produced therefrom relative to those obtained with untreated reclaimed sand. Methods for producing foundry cores and molds which incorporate such a treatment process are also provided by this invention, as are raw batch formulations.

Abstract: A process for improving the flowability of resin coated sand which comprises the use of a flow promoter with the mixture of sand and resin. Also provided is a foundry mix comprising foundry sand, a resin binder and the flow promoter, as well as a process for making foundry cores and molds using the foundry mix. The resins are ester-curable alkaline phenolic resole resins. The flow promoter is selected from the group consisting of fatty acids, fatty alcohols, fatty amines, fatty amides and fatty alkanolamides.

Abstract: Modified benzylic ether resole resins and process for their preparation. The resins are prepared by treating a phenol with a molar excess of aldehyde in the presence of a divalent metal ion catalyst at a pH below 7 followed by further reaction at a pH above 8 in the presence of an alkaline catalyst. Alkaline solutions of the resins are used as foundry binders in an ester cure process.

Abstract: A binder composition which comprises an aqueous alkaline solution of a phenolic resole resin and an additive wherein the additive is phenoxyethanol or a derivative of phenoxyethanol.

Abstract: A binder composition which comprises an aqueous alkaline solution of a phenolic resole resin and an additive wherein the additive is phenoxyethanol or a derivative of phenoxyethanol.

Abstract: A proppant composed of particulate material coated with a solid thermosetting resin that can consolidate and cure at tempertures below about 130.degree. F. An acidic catalyst in a solvent system is used to cure the resin underground.

Abstract: A terpolymer is prepared from phenol, furfuryl alcohol and formaldehyde wherein a substantial amound of the furfuryl alcohol is catalytically reacted by means of a water soluble multivalent metal salt catalyst, and wherein the reaction is carried out under essentially hydrous conditions.

Abstract: A foundry shell core and mold composition comprises particulate matter coated with a curable phenolic-furan resin. The process for making the resin coated particulate matter substantially eliminates the sue of hexamethylene tetramine.

Abstract: The present invention relates to coated particulate matter wherein the particles are individually coated with a cured combination of phenolic/furan resin or furan resin to form a precured resin coating on a proppant such as sand, thereby substantially improving the chemical resistance of the proppant over one having a straight phenolic precured coating.Another embodiment of this invention involves the use of multiple resin coatings on the particulate matter to form a final layered coating containing the desired amount of cured resin. This multiple coating of particulate material results in a final coated product that has a smoother and more uniform surface than particulate material having its entire resin coating applied in a single operation.

Abstract: Furfuryl alcohol-formaldehyde resins which can be prepared by using a water soluble multivalent metal salt as the catalyst, thereby eliminating the use of an acid catalyst and the necessary attention it requires.

Abstract: A suspension or solution containing an acid-curable fluoride-containing resin which is useful in a foundry process is disclosed. The fluoride-containing resin is curable at room temperatures and above by the addition of a strong acid catalyst. The resin is preferably a phenolic resole resin or a furan-type resin. The fluoride-containing resins, when used in a foundry process are preferably admixed with a foundry sand and a strong acid catalyst. The coated sand is then shaped into the form of a foundry core and is allowed to cure at room temperature or above to a foundry core having excellent tensile strength.

Abstract: A foundry core composition containing a rapid-curing furfuryl alcohol and phenolic resole resin system useful in the "hot-box" process is provided. This composition includes an acidic curing agent of low toxicity whose catalytic activity is enhanced by the presence of a water-soluble polymeric polyhydroxy compound.

Abstract: An improved process is provided for preparing a product containing particles individually coated with a cured, thermoset phenolic resin. The process comprises mixing particulate matter with an uncured resin and a lubricant at a temperature which causes curing of the resin. The product obtained by this process shows superior properties as a propping agent for treating subterranean formations.

Abstract: Modified benzylic ether resole resins and process for their preparation. The resins are prepared by treating a phenol with a molar excess of aldehyde in the presence of a divalent metal ion catalyst at a pH below 7 followed by further reaction at a pH above 8 in the presence of an alkaline catalyst. Alkaline solutions of the resins are used as foundry binders in an ester cure process.