Abstract: Process for the continuous bulk production of high impact vinylaromatic copolymers in which the vinylaromatic monomer, and if present, a comonomer selected from the group consisting of acrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid and their alkyl- or cyclo-alkyl-esters containing from 1 to 8 carbon atoms in the alkyl group, the rubber, a part of the diluent solvent and the catalyst are premixed in a premixer at a temperature under 100.degree. C. and fed to a plug-flow agitated tubular reactor, which is divided into several stages or zones. The excess mixture is recycled to the premixer and the remaining part of the diluent solvent is injected into the top of the reactor to prevent the formation of incrustations. In the first zone of the reactor, the temperature and the residence time of the mixture are regulated so to have the halving the catalyst life.

Abstract: A process for the devolatilization of polymer solutions including:(a) feeding the solution to a zone of indirect thermal exchange in which the ratio between the surface of thermal exchange and the flow per hour of the solution is over 80 m.sup.2 /m.sup.3 /h;(b) moving the solution forward into each channel at a speed below 0.5 mm/second;(c) keeping the solution of the polymer in each channel for about 120-200 seconds; and(d) separating the volatile components from the devolatilized polymer solution.

Abstract: A thin-layer evaporator particularly suited for treating high-viscosity fluids, including a treating chamber surrounded by a heating or cooling shell, and a rotor equipped with feed and thrust elements. The feed and thrust elements include at least two axial, equidistant and staggered rows of blade members having the same pitch and sloping with respect both to the rotor axis and to the axial plane passing through their connection line; each member being offset, with respect to the members of the adjacent rows, by a space equal to the half pitch of the member.