Effect of oxidized starch and inorganic filler on paper properties

Preparation of dialdehydic and dicarboxylic starch were studied. The effect of these materials on the mechanical properties of paper sheets and retention of filler e.g. kaolin and ground CaCO3 was investigated. Discarboxylic starch increased the mechanical properties and also increased the retained filler. The percent of the retained filler was decreased by increasing the amount of added filler; the retained amount of CaCO3 was higher than that in case of kaolin. Addition of CaCO3 in contrary to kaolin increased the mechanical properties of the produced paper sheets. Addition of filler increased the optical properties e.g. opacity and brightness of paper sheets. Infrared spectroscopy of the prepared cationic starch derivatives shows a new band at 1715 cm-1.