Borden, Inc.

James H Williams

A process for preparing a ureaform type resin fertilizer as an aqueous suspension which is stable and preferably has an Availability Index of at least 70 which, in a preferred embodiment, comprises: adding urea to an acidic solution of formaldehyde having a pH of 0.25 to 1.75 at a rate of addition to keep the temperature below 98.degree. C. until the mole ratio of formaldehyde to urea is from 3.5:1 to 2.6:1; adjusting the pH of the reaction mixture to between about 5.2 and 6.8 and the temperature from about 75.degree. C. to 92.degree. C. and adding urea until a formaldehyde to urea mole ratio of 0.5:1 to 1.8:1 is attained and the nephelometric turbidity of the reaction mixture is in the range of 200 to 800 NTU units; and then neutralizing the reaction mixture to a basic pH not exceeding about 8.5.

Urea-formaldehyde fertilizer suspensions

Urea-formaldehyde precursors are produced in a two-stage process. In the first stage, urea is slowly added to an acidic solution of formaldehyde at a pH of 1.0 or less, at a rate that maintains the temperature at 50.degree. C. but not in excess of 98.degree. C. When an F/U mole ratio of 3.25:1 to 2.5:1 has been attained, the pH is adjusted to the basic side, generally from about 7.2 to about 8.0. In the second stage, additional urea is added to the condensate produced in the first stage, to attain an F/U mole ratio of 3.0:1 to 2.5:1. The condensate and precursor have fertilizer applications. The precursor is useful in urea-formaldehyde resin production.

Urea-formaldehyde precursor

Process for preparing a urea-formaldehyde resin in an aqueous formulation particularly intended for use as a particleboard binder. The resin cures to be low emitting. In the cured state, the resin has more than twice as many methylene groups as methylene ether groups, and generally is characterized by residual formaldehyde that is at least 40% and often 50% less than that of a cured resin of the same F/U mole ratio but produced by an initial base catalyzed methylolation procedure of which the primary prepolymer products are mostly monomethylol and dimethylol urea precursors, followed by condensation.

Low emitting aqueous formulations of aminoplast resins and processes for

A process for preparing a urea-formaldehyde base resin having a F/U molar ratio of 1.0:1-1.2:1, that is hydrolytically stable, which comprises adjusting a formaldehyde solution to a pH of 0.5-2.5, slowly charging urea to said formaldehyde solution while maintaining the temperature at 40.degree.-70.degree. C., neutralizing the reaction mixture after obtaining a Gardner viscosity in the range of T+-V+, then adding the final charge of urea and permitting equilibration.

Hydrolytically stable urea-formaldehyde resins and process for

A process for bonding lignocellulosic material under heat and pressure, where the bonded lignocellulosic material is characterized by a low emission of formaldehyde, which comprises applying a binder to said lignocellulosic material, said binder comprising a urea-formaldehyde base resin having a ratio of formaldehyde to urea of 1.0:1-1.2:1, said base resin having essentially no free formaldehyde and said base resin when cured containing substantially more methylene groups than methylene ether groups, consolidating said lignocellulosic material and curing the binder.

Wood composites of low formaldehyde emission

This foaming system includes a foaming agent solution and a resin solution. The foaming agent includes the relative amounts of 15 to 30 parts by weight of a salt of an alkyl diphenyl oxide sulfonate, 10 to 25 parts of 85% phosphoric acid and 15 to 25 parts urea, all in an aqueous solution. The resin solution includes a resin prepared by reacting 1 to 2.4 mols of formaldehyde per 1 mol of urea, 6.5 to 500 mmols polyethylene glycol as foam charring agent, 0.3 to 1.2 mmols of calcium carbonate as uniform foam cell size agent, 3 to 310 mmols of dicyandiamide as foam hydrolysis resistance agent, 2 to 30 mmols of sodium bromide as foam aging agent, and sufficient water to make a 35 to 45% solution. In preparing the foam, one part by weight of the foaming agent solution of about 5% solids concentration is aerated and then 1.0 to 1.5 parts by weight of the resin solution is sprayed thereon to obtain foam with an average linear shrinkage of about 0.25%.

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Louisville, KY, United States of America

James H Williams