Schobert-Csongor; D. G.; Schott; N. R. U.S. Pat. 5,951,159 (1999)

A method of mixing of plurality of compounds on a single screw extrusion machine comprises the steps of attaching a barrel of a dynamic mixer apparatus onto the down stream end of a barrel of the extrusion machine, arranging a support shaft in the dynamic mixer apparatus to rotatively carry a plurality of rotors and stators within the dynamic mixer barrel, machining at least one introduction port through the dynamic mixer barrel at a position radially adjacent a rotor and attaching a satellite extrusion mixer to the introduction port so that additives may be introduced at a desired location best suited for the additive. Additionally, the introduction port may used as a withdrawal port to take samples of the mix. Alternately, the rotor of the dynamic mixer may be positioned to present a shaft with a rotor of opposite hand to provide a flow retarding characteristic.