Abstract
By measuring the swelling of samples in glacial acetic acid, the cornification of cellulose and the reactivation of the cornified cellulose were investigated, and the results obtained are as follows.
(1) In the dehydrating course of drying, the cornification develops increasingly after the water content has fallen below 50% in the case of native cellulose or below 80% in the case of cellulose treated with 10% NaOH beforehand.
(2) The cornification is appreciably inhibited by drying after replacing water with organic liquid, and the smaller the surface tension, affinity to hydroxyl group, and the polarity of the liquid, the greater the preventing action of the liquid.
(3) If the cellulose not cornified in drying is placed in the room of moderate humidity, the cornification takes place markedly during storage.
(4) The cornified cellulose is reactivated by treating it with proper liquid; the greater the cohesive energy density of the liquid, the higher the activity as reviving reagent. Acetic acid displays its reviving action only at moderately higher temperature.
(5) Mechanical grinding is exceedingly effective in the reactivation of the cornified cellulose.
