Abstract: A process for admixing additives to plastics and simultaneously removing volatile constituents in a horizontal devolatilizing extruder. Taken in sequence in the direction of flow, the additives are first introduced into the devolatilizing extruder from above, and the plastic melt, solution or dispersion is then introduced from below, while the bulk of the volatile constituents are withdrawn from the devolatilizing extruder at an orifice located vertically above the point at which the plastic is fed in. The process permits the removal of volatile constituents with simultaneous admixture of additives during aftertreatment of plastics, in a single step and at very high throughputs.

Abstract: A continuous process for the polymerisation of olefinically unsaturated monomers in bulk or in solution in which at least a portion of the low-viscosity materials to be fed to the polymerization zone is thoroughly mixed with a portion of the high-viscosity contents of the polymerization zone in a mixing zone disposed upstream of the polymerization zone, which mixture is then continuously fed to the polymerization zone. The resulting polymers have a uniform composition and a narrow molecular weight distribution. They may be converted to shaped articles by thermoplastic methods.