Abstract: A devolatilizer apparatus and method for devolatilization of viscous polymer liquids yields polymer products with very low levels of residual volatile components. A stream of liquid polymer is dropped through a first vacuum chamber, thereby removing a portion of the volatile components. The stream is collected at the bottom of the first chamber, and is re-circulated to a manifold and liquid distributor assembly in a second chamber in the same vessel. The stream flows by gravity through the second chamber, which is maintained at a higher level of vacuum than the first chamber. Improved devolatilization is accomplished by exposing the polymer liquid to multiple stages of vacuum in a single vessel. The first chamber may be located generally above the second chamber, but in the same vessel, with the stream falling through the second chamber a first time before re-circulation to the manifold.

Abstract: The present invention relates to an improved falling strand devolatilizer apparatus and method for devolatilization of viscous solutions to yield viscous liquids with lower content of volatile solvents, unreacted components, and reaction byproducts. The novel apparatus utilizes a devolatilization system comprised of a single vessel with two or more liquid compartments or zones, a recirculation loop, and one or more manifold and stranding distributor assemblies to divide the viscous liquid stream into a plurality of strands for effective devolatilization. A stranded stream of solution is dropped through a first zone of the chamber and collected at the bottom, the stream is recirculated, and then dropped through a second zone of the vessel and separately collected. Devolatilization is accomplished by stranding thi falling streams to optimum parameters.

Abstract: The present invention relates to an improved falling strand devolatilizer apparatus having a plurality of stages for devolatilization providing polymers with lower residual monomer and/or volatile contents. The novel apparatus utilizes a final flash tank having two flash compartments that share a common heating and vacuum system wherein a recycle line transfers polymer melt from the first compartment to the second compartment for additional devolatilization.