DISSOLUTION STUDIES IN ORGANIC-SOLVENTS FOR EVALUATING HYDROGEN-BOND MATRIX OF CELLULOSE IN THE GROUND MIXTURE

Benzoic acid crystals were ground with microcrystalline cellulose. In order to evaluate the hydrogen-bond matrix of cellulose in the ground mixture, dissolution experiments were carried out using organic solven ts as dissolution media. With prolongation of grinding, benzoic acid w as gradually amorphized and the dissolution of benzoic acid from the g round sample was significantly suppressed in cyclohexane. This result was considered to be due to the dispersion of benzoic acid molecules i n the hydrogen-bond matrix of cellulose through the grinding process. From experiments using a series of organic solvents, it was found that the amount of benzoic acid dissolved was correlated to the polarity o f solvents. On the other hand, moisture in the solvent and primary hyd roxyl groups in solvent molecules were considered to be effective fact ors for enhancing;the dissolution of benzoic acid from the ground mixt ure.