(352a) Emulsion Formation and Mitigation in the Liquid-Liquid Extraction of Polycarbonate Co-Polymers

The interfacial process for manufacturing polycarbonate polymers and co-polymers includes a liquid-liquid extraction step for polymer purification. This process depends on efficient liquid-liquid mass transfer followed by clean separation of the organic and aqueous phases. The chemical nature of the polymer can affect the interfacial properties and result in emulsification of the mixture. This results in poor purification performance and manufacturing capability issues.

An example of a new polycarbonate co-polymer with the tendency to emulsify is reviewed. Lab and pilot scale experiments/measurements have been used to identify the key process and product variables. Analysis tools included droplet microscopy and phase separation rates to evaluate emulsion stability and separation kinetics. These results have been used as the basis for process improvements during the scaleup of the polycarbonate co-polymer.