On the Mechanism of Destruction and Oxidation of Starch for the Production of Plasterboard Sheets (PBS)

The technological process of PBS production requires careful control of the phase composition of the gypsum binder used, as well as compliance with the drying modes of the sheets. This is necessary in order to ensure the adhesion of the gypsum core to the cardboard and, as a result, to give the sheets the required mechanical and physical properties. The use of various kinds of modified starches in the production technology of PBS makes it possible to achieve the required adhesion with fluctuations in the phase composition of the binder and deviations in the drying mode of products. Considering this, it becomes obvious that the characteristics of modified starches have a significant effect on the quality of PBS. The study of existing standards regulating the quality indicators of starch derivatives showed the absence of parameters reflecting the effectiveness of their use in the production technology of PBS. In this paper, the structural features of the most widely used types of modified starch are considered. The paper summarizes information about the mechanism of adhesion of the gypsum core to cardboard, the factors influencing this process, the mechanisms of starch destruction and oxidation, and also offers a list of quality indicators of starch derivatives and the requirements for them. It is shown that the effectiveness of the use of modified starches in the production of PBS is achieved by regulating the direction and depth of the processes of destruction and oxidation.