Apparatus for polymerizing liquids

Abstract

Abstract Apparatus for treating viscous liquids, as in the polymerization of polyester prepolymer, while the liquid is being transported through one or more reaction chambers in a closed vessel by a pair of closely intermeshed, horizontal, counterrotating screws extending across each chamber. The screws are partially immersed in the liquid and distribute it on their outwardly moving upper surfaces in layers thin enough for the elimination of gaseous products without excessive frothing under subatmospheric pressures in a vapor space extending over a substantial area of the surfaces of the screws. A small nip clearance between the intermeshing screw flights provides a wiping action that prevents accumulating material thereon and exposes fresh surfaces of the polymerizing liquid as well as regulating the thickness of the layer thereof carried upwardly by each screw even when great increases in viscosity occur during polymerization. Gastight seals between adjacent chambers are obtained by completely enclosing the intermeshing screws in close fitting barrels or tunnels and providing restricted orifices therein whereby the enclosed screw sections become completely filled with the polymerizing material.

Inventors

• 👤 Jack E Crawford
• 👤 Ralph W Edwards
• 👤 Edward D Henze
• 👤 William C L Wu

Bibliographic Details