NMR structural elucidation of amino resins

• Published in: Journal of applied polymer science Vol. 91; no. 6; pp. 3504 - 3512
• Main Authors: Angelatos, A. S., Burgar, M. I., Dunlop, N., Separovic, F.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 15.03.2004; Wiley
• Subjects: Applied sciences; copolymerization; Exact sciences and technology; NMR; Organic polymers; Physicochemistry of polymers; Polycondensation; Preparation, kinetics, thermodynamics, mechanism and catalysts; relaxation; resins; structure; copolymerization; resins; Nitrogen 15; Molecular structure; Self condensation; relaxation; Condensation polymerization; NMR spectrometry; Experimental study; structure; Aminoplast; NMR; Investigation method; Copolycondensation; Reaction mechanism; Proton; Melamine resin
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.13538

Urea formaldehyde, melamine formaldehyde, and melamine urea formaldehyde (MUF) are important industrial amino resins that find application in numerous diverse areas, most notably in the bonding of wood products. To understand the physical properties of these amino resins and, hence, optimize their performance, a knowledge of their chemical structure is necessary. This article reports the use of NMR spectroscopy to acquire this information in the solid and liquid states. 13C‐NMR experiments, supported and augmented by 1H‐NMR and 15N‐NMR results, showed that the two stages of resin synthesis, methylolation followed by condensation, occurred in each type of resin. However, in the various MUF samples analyzed, the second step appeared to be predominantly the self‐condensation of melamine and urea rather than the cocondensation of melamine and urea. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3504–3512, 2004