21243-68-5Relevant articles and documents
Spectral assignments and reference data: A 13C NMR study of the methylol derivatives of 2,4′- and 4,4′-dihydroxydiphenylmethanes found in resol phenol-formaldehyde resins
Fisher, Thomas H.,Chao, Ping,Upton, Cindy G.,Day, Anthony J.
, p. 747 - 751 (2007/10/03)
A total of 13 of the 16 possible methylol derivatives of 2,4′- and 4,4′-dihydroxydiphenylmethane have been synthesized, isolated, and identified. These compounds are found as intermediates in the cure process of resol phenol-formaldehyde (PF) resins. Analysis of the 13C NMR spectra (in acetone-d6) of these compounds provided a way to evaluate the seven methylolphenol ring types (methylol derivatives of 2-hydroxyphenyl and 4-hydroxyphenyl rings) found in typical resol PF resins using the ipso carbon region from 150 to 160 ppm. A simple diagnostic test was developed using the chemical shift values of the methylol methylene carbon atoms to identify the presence of intermediates containing either a 2-hydroxyphenyl or a 4-hydroxyphenyl ring. Using these data it is now possible to analyze the major components in extracted prepreg PF resins. Copyright