The Dispersion of Protein in Aqueous Formaldehyde Solutions.

Abstract

The reaction between formaldehyde and proteins is of paramount importance in the development of protein plastics (2), coatings, sizes, adhesives, and fibers. It has been used in these industries as a so-called hardening process for many years.In processes that employ protein dispersions it has not oeen found possible to combine the formaldehyde with the protein before use, because they react with each other at a rather rapid rate to cause the formation of a precipitate. Therefore the formaldehyde treatment must be a separate step in the process where it is used. Attempts have been made to simplify such processes by using certain compounds in the protein dispersion that give a delayed formaldehyde reaction, but as yet they have not attained any marked success.In the early literature on the protein-formaldehyde combination, which has been reviewed by Gortner (5), it has been postulated to be a reaction between the formaldehyde and the free amino groups of the protein.Many studies have been made on the analogous reaction between formaldehyde and amino acids (6), but even for these simpler systems there has been no general agreement on the structure of the compounds formed.Recently attempts to define the protein-formaldehyde linkage by means of x-ray diffraction studies have been made (4), but up to the present time they have yielded no characteristic pattern.Because of the desire for obtaining greater water resistance in the abovementioned protein products and because the formaldehyde reaction appears to be the most promising means of accomplishing this result, a

Viscosity Patterns of Peanut Protein Solutions.

“…The magnitude of this effect is illustrated by comparison of the curves for preparations P3 and P3-L. The maximum viscosity shown in the former was 10 poises and that in the latter, 1000 poises. Removal of the soluble, nonprotein material also raised the nitrogen content of the protein (P3) from 16.06 to 16.56% (P3-L).…”