ISSN:
0360-6376
Keywords:
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The mechanism of the reaction of phenols with formaldehyde was studied by computer simulation. At first starting molecules were stored in a computer and the hypothetical reaction yielded conditions like the reactivity ratio of hydroxymethyl group to formaldehyde and that of orthohydrogen to parahydrogen. The molecular weight distribution of the hypothetical product in the computer was compared with that of the prepared resin determined from GPC measurement. Reaction mechanisms were discussed. We also confirmed, by computer simulation, that the rate of methylenation is larger than that of hydroxymethylation in an acid-catalyzed system and that the reactivity ratio of hydroxymethyl group to formaldehyde is 5-12 for the reaction of phenols such as o-cresol, p-cresol, and phenol with formaldehyde. The opposite results were obtained in a base-catalyzed system. It also became apparent that information regarding molecular structures, such as the number of branches, the number of phenolic nuclei in the longest chain, and the number of o,o′-,o,p′- and p,p′-methylene linkages, can be obtained by computer simulation. The most probable values of these factors for 10 mer of a phenol-formaldehyde condensation molecule are 2, 7, 2, 5, and 2.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1981.170190703
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