ESTIMATION OF HANSEN SOLUBILITY PARAMETERS FOR (HYDROXYETHYL)-CELLULOSE AND (HYDROXYPROPYL)CELLULOSE THROUGH MOLECULAR SIMULATION

In this paper we examine the solubility properties of two broad families of cellulosic surfactants ((hydroxyethyl)- and (hydroxypropyl)cellulose) using molecular models and molecular dynamics simulations. The calculations were performed by building models of both the amorphous condensed state and the vacuum state. The condensed state models were constructed with single chain conformations in periodic cells with backbone torsion angles populated according to rotational isomeric states (RIS) determined for the single chains. For HPC-253, a (hydroxypropyl)cellulose for which experimental results have been published recently, we found good agreement between the simulations and experimental results. Our simulations predict that the three-dimensional solubility parameters for this class of surfactants are dominated by the contributions from polar and hydrogen bonding interactions. This result differs from the predictions of group additivity tables.