Preparation of a Melamine-Phenol-Formaldehyde Resin

To a resin flask equipped as previously described are added 50 gm (0.4 mole) of melamine, 37.3 gm (0.4 mole) of phenol, and 119gm of 40.3% (1.6 moles) of formaldehyde. The pH is adjusted to 3-6, and the solution is heated to 95°C and kept at that temperature for hr. At this point the solution forms two layers. The entire reaction mixture is blended with 60 gm of cellulose, dried, and ground up to a fine powder. The resulting material is suitable for use as a molding resin and thermosets at 150°C to an infusible solid. 

Benzoguanamine (m.p. 227°C) is prepared by the reaction of dicyanodiamide with benzonitrile. 

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