Process for the devolatilization of polymer solutions
AssigneeMontedipe S.p.A.
InventorsAndrea Mattiussi, Claudio Buonerba, Franco Balestri, Dino Dall'Acqua, Savino Matarrese, Italo Borghi
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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.
Claims15
A process for the devolatilization of polymer solutions consisting of:
- (a) feeding the polymer solution to a zone of indirect thermal exchange comprising a plurality of channels arranged in parallel with respect to one another, heated to a temperature higher than the temperature of vaporization of the volatile components and up to the boiling temperature of the solution, wherein the ratio between the whole surface of thermal exchange, expressed in m.sup.2, and the flow per hour of the fed polymer solution, expressed in m.sup.3 /h, is above 80 m.sup.2 /m.sup.3 /h;
- (b) moving the polymer solution forward into each channel at a speed below 0.5 mm/second and the pressure of the polymer solution at the inlet of the channels ranges from 2 to 5.10.sup.5 Pascal;
- (c) keeping the polymer solution in each channel for a period of time ranging from 120 to 200 seconds, in order to evaporate at least 90% of the volatile components from said polymer solution;
- (d) separating the volatile components from the devolatilized polymer solution;
- (e) wherein the temperature of the polymer solution is at least 50 centigrade degrees over a glass transition temperature Tg of the polymer;
- and
- (f) wherein the difference between the temperature of a heating medium and that of the polymer solution leaving the channels is below 10 centigrade degrees.
Dependencies are inferred from the claim text.