Melamine salts as hardeners for urea formaldehyde resins

Various salts derived from melamine and organic acids were prepared and use d as melamine substitutes for melamine urea formaldehyde (MUF) resins. The synthesis of these melamine salts and a detailed characterization of their stoichiometry are described. All salts form 1:1 or 1:2 stoichiometries in a homogeneous reaction. They crystallize during cooling of the hot and dilut ed reaction mixture. Both C-13-NMR and N-15-NMR data are reported and point toward the formation of real ionic structures. Most salts have higher wate r solubility than that of pure melamine and are tested for their ability to substitute melamine in MUF resins. The mechanical and chemical properties of plywood panels made up of traditional MUF resins and mixtures of UF resi ns with melamine salts are investigated. (C) 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1654-1661, 2001.