Melamine–formaldehyde resins: Molecular species distributions of methylolmelamines and some kinetics of methylolation

Abstract

Abstract The addition reaction between melamine and formaldehyde has been studied by the direct observation with NMR spectroscopy and high‐speed liquid chromatography. All of the nine methylolmelamines, including two isomers of di‐, tri‐ and tetramethylolmelamine could be assigned. The liquid‐chromatographic technique was applied to the quantitative analysis of methylolmelamines and the free formaldehyde contents in the reaction mixtures, and the molecular species distributions were determined. By using these quantitative methods, the equilibrium constants and rate constants for the individual reversible reactions were estimated.