Knowledge Bank

The polarized infrared spectra of well oriented crystalline cellulose and chitin samples have been investigated. From those data it seems highly probable that in these crystals, an intramolecular hydrogen bound is formed between the $C3$ hydroxyl group of one glucose residue and the ring oxygen of the next residue. An intramolecular hydrogen bond involving the primary hydroxyl group has often been suggested by a number of investigators. It was found that in the cellulose I and cellulose II lattices, such an intramolecular hydrogen bond cannot be formed. However, this type of bond may exist in the chitin crystal.