Studies in the Reaction of Formaldehyde with Unmodified, Modified, and Dyed Celluloses

Abstract

The reaction of formaldehyde with five cellulosic fiber substances has been studied at 30° C. The combined formaldehyde values (CF) at any given time are in the following proportion: Cotton cellulose (native): 1.00 Cotton cellulose (mercerized under tension): 1.31 Cotton cellulose (mercerized without tension): 1.49 Viscose rayon : 1.97 Cuprammonium rayon: 2.31 Values of fiber crystallinity, moisture regain, oxidative susceptibility, and equilibrium uptake of direct dye for these fiber substances have been related with their CF values at given times of reaction. A mechanism has been put forward to explain the anomalous behavior of viscose rayon towards formaldehyde. A method has been suggested for determining the relative accessibility of these fiber substances to formaldehyde.