Dispersants play a crucial role in the suspension polymerization process for the production of polymer resins. The dispersant package used in industry processes often involves two or more macromolecules (such as polymers or proteins). How these molecules behave at the oil-water interface is not very well understood, which hinders the development of new dispersant packages for existing or new polymer resins. In this study, we use the molecular dynamics modeling technique to simulate the activity of one dispersant package (gelatin and PADMAC) at the oil-water interface. The simulation results show that the charged amino acids in gelatin keep the gelatin at the interface while the non-polar region is immersed in the oil phase. The PADMAC polymer is not soluble in the oil phase and stays in the aqueous phase. Strong electrostatic interactions between the cationic backbone of PADMAC and the charged groups in the gelatin anchor the PADMAC to the gelatin and therefore to the interface. This shows that PADMAC, in conjunction with gelatin, can adsorb to the oil-water interface and thus stabilize oil droplets in the suspension polymerization process. The fundamental understanding gained from this study would be useful in the design of new dispersant packages for suspension polymerization.

Molecular dynamics simulation of dispersant activity at oil-water interface

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.