Crosslinking statistics, 2. Relative reactivities of amylose hydroxyl groups

Reproducibility of crosslink distribution in polysaccharides crosslinking depends on the homogeneity of the reaction mixture. If the condition of reaction homogeneity is met, the distribution of substituents (or crosslinks) should directly determine the relative reactivities of the functional groups. The resulting molecular size distribution of fragments of monosaccharide units connected by crosslinks in such a case should be given by the statistical laws of network formation. This principle is exemplified on amylose crosslinked by epichlorohydrin in a homogeneous water‐alkali medium. The relative reactivities of functional groups are investigated in two ways: (1) by specific reactions; (2) calculated theoretically from the molecular size distribution of fragments of crosslinked glucose units. Good agreement of both results supported the above mentioned assumptions. The reactivity of amylose hydroxyls increases strongly in the order OH‐3