Salicylic Acid → Melamine formaldehyde

Participants

Reaction Steps

In water, 138 g of salicylic acid and 126 g of melamine were stirred at 20 to 30° C., and in the presence of sodium hydroxide catalyst, 284 g of formalin was added dropwise under cooling. The reaction was then carried out at 90° C. for 2.5 hours. To maintain the pH of the reaction system at 8.5 to 9.5, sodium hydroxide was gradually added during the reaction. The reaction mixture was then adjusted to pH 7 to 8 with p-toluenesulfonic acid and then cooled and the unreacted starting materials and part of the water of condensation were removed from the system under reduced pressure to provide a liquid melamine-formaldehyde primary condensate having a nonvolatile matter content of 75% and a viscosity of 19000 cps (Compound E).

Provenance & Evidence