Methylolation of melamine with incipient condensation. I. Synthesis and characterization

摘要: This work investigates five reactions between melamine (M) and formaldehyde (F) at pH = 9.0, with initial F : M ratios of 2. The samples were analyzed by size exclusion chromatography (SEC), volumetric techniques, (1H 13C) NMR. Condensation was quantified the SEC measurements. In experiments 38 48°C, condensation almost negligible, reversibility methylolation determined that equilibriums reached in primary, secondary, tertiary amines. 60, 70, 90°C, significant, but all cases, mass fraction single-ringed species larger than two or more rings per molecule. following estimated combining measurements: number-average molecular weights, average functionalities reactive H's, methylols, methylene bridges, ether bridges. dissolution water essentially instantaneous. measurements are employed next article this series for adjusting a novel mathematical model. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci,