The term ‘‘melt extrusion’’ implies the processing of polymeric materials at
temperatures above their glass transition temperature (Tg) in order to eﬀect molecular-level mixing of active compounds and thermoplastic binders and/or
polymers (1). These processes are increasingly being performed on twin-screw
extruders as a result of their superior mixing capabilities and narrow residence
time distribution (2,3). A narrow residence time distribution is critical when
processing thermally sensitive active compounds.