SUSPENSION POLYMERISATION METHOD Russian patent published in 2012 - IPC C08F10/02 C08F2/12 C08F2/14 C08F297/08 

FIELD: chemistry.

SUBSTANCE: method is carried out in at least two reactors connected in series, where 20-80 wt % of a first polymer is obtained in a suspension in a first reactor and 80-20 wt % second polymer is obtained in a suspension in a second reactor in the presence of the first polymer. One of the polymers is a low molecular weight polymer and the other is a high molecular weight polymer. A stream or suspension containing the obtained polymer is removed from the second reactor and transferred into a stripping reservoir operating under conditions such conditions as pressure and temperature through which at least 50 mol % of the liquid component of the suspension or the non-polymer component of the stream entering the stripping reservoir is removed from the stripping reservoir in vapour form. Stream or suspension concentration of components entering the stripping reservoir, having molecular weight lower than 50 g/mol, C_{light products} (mol %), satisfies the inequality C_{light products}<7+0.07(40-T_c)+4.4(P_c-0,8)-7(C_H2/C_Et), where T_c and P_c respectively denote temperature (°C) and manometric pressure (MPa) at the point where vapour from the stripping reservoir is condensed, and C_H2 and C_Et denote molar concentration of hydrogen and ethylene, respectively, in the stripping reservoir.

EFFECT: realising the process without need to recompress the liquid evaporated in the first stripping reservoir.

17 cl, 3 tbl, 3 ex