An attempt has been made to elucidate the nature of the reaction between alkaline hypochlorite and granular wheat starch. With this end in view various analytical determinations were carried out on starch samples oxidized under well‐determined conditions. The reaction was found to be nonspecific, its main results being the formation of functional groups and the scission of glucosidic bounds. The functional groups formed were mainly carboxyls, some carbonyl formation taking place at lower pH values. The consumption of about 0.05 atom of oxygen/AGU resulted in an extensive degradation of both starch components. There are indications to the effect that degradation is random in type. On that assumption, 0.5 to 1 glucosidic bonds in 100 were scinded, each scission being accompanied by the formation of about two carboxyl groups and by an overall consumption of 4–5 oxygen atoms. The reaction apparently took place in the amorphous part of the granule. The amylose‐amylopectin ratio, as well as the granule size remained unchanged. More than one‐quarter of the total oxygen consumed reacted with the dissolved portion of the starch as the result of the oxidation.

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Graded acid hydrolysis of a soluble wheat bran hemicellulose containing L-arabinose (50%), D-xylose (38.5%), and D-glucuronic acid (9.0%) preferentially removed the L-arabinose giving an insoluble acidic polysaccharide in approximately 25% yield by weight. Methylation studies, periodate oxidation data, and hypoiodite end group estimations showed that the degraded polysaccharide was composed of repeating units of 7-8 D-xylopyranose residues joined by β,1 → 4 linkages. To this repeating unit, one D-glucuronic acid unit was attached by a 1 → 2 glycosidic bond. The cellulolytic enzyme of Myrotheciumverrucaria, which is specific for β,1 → 4 glycosidic linkages, hydrolyzed the degraded polysaccharide although it had no effect on the parent hemicellulose

A uniform rigorous mathematical treatment is presented for the random degradation of chain polymers, including the three fundamental initial states, viz., (a)a finite single chain (b)a number of chains of equal length, and (c)a number of chains of varying lengths. Limiting expressions are derived for the number fraction and weight fraction of chains of a given degree of polymerization, theoretically obtainable for a given degree of degradation in all three cases. The stochastic approach is employed for the derivation of the mathematical expression for the degree of degradation as function of time. It is assumed in the derivation that the probability P that a given bond still unbroken at the time t will break in the time interval between t and t + Δt is of the form P = φ(t)Δt, where φ(t)is not necessarily a constant. Instead of the well known formula α(t)= 1 − exp { − kt} an empirical formula α(t)= 1 − exp { − ktm} is proposed; this formula includes the former as' a special case (when φ(t)= const.), and is shown to better fit the experimental results obtained in studies on the degradation of cellulose and of polystyrene solutions.