You are here: Home
/ Publication Information
Title: Analyses of cocondensation of melamine and urea through carbon 13 enriched formaldehyde with carbon 13 nuclear magnetic resonance spectroscopy
Author: Bunchiro, Tomita; Hse, Chung-Yun;
Source: Mokuzai Gakkaishi 41(5):490-497
Publication Series: Miscellaneous Publication
Description: The urea-formaldehyde (UF) resins, melamine-formaldehyde (MF) resins, and melamine-urea-formaldehyde (MUF) cocondensed resins were synthesized using the labeling method with 13C enriched formaldehyde unde neutral conditions and their 13C-NMR (nuclear magnetic resonance) spectra were analyzed. The remarkable down-field shifts by 1.2 to 2.7 ppm of the corresponding signals of UF and MUF resins were recognized by the addition of water to the DMSO-d4 solution of NMR samples. According to the results, the chemical shifts were corrected by measurements of DMSO-d4 solution free of water. The formation of cocondensed methylene linkages was induced mainly by the reaction of methylol groups of melamine and primary amino groups of urea residue, and that of cocondensed dimethylene ether linkages was apt to take place in the case of a shortage of primary amino groups of urea residue. In the reaction of methylolurea and dimethylolmelamine, methylol groups of urea residue also were found to react with the primary amino rgoup of methylolmelamine to form cocondensed methylene linkages.
Keywords: Melamine/urea, formaldehyde, cocondensation, C-13 NMR, C-13 enriched formaldehyde
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
- You may send email to email@example.com to request a hard copy of this publication. (Please specify exactly
which publication you are requesting and your mailing address.)
XML: View XML
Bunchiro, Tomita; Hse, Chung-Yun 1995. Analyses of cocondensation of melamine and urea through carbon 13 enriched formaldehyde with carbon 13 nuclear magnetic resonance spectroscopy. Mokuzai Gakkaishi 41(5):490-497
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility