Patent ID: 8404781

Claim:
A semi-continuous integrated process for producing high impact vinyl aromatic (co)polymers, which comprises: a. anionic polymerizing at least one monomer of butadiene in a batch reactor, in the presence of an organolithium compound and a non-polar solvent having a boiling point lower than 130° C.; b1. effecting a chain termination phase of the polymer based on butadiene, at the end of the polymerization, with at least one halogen derivative having the general formula: R 3 -M-X (1) wherein X represents a halogen, M represents an element of Group IV A, and R is a C 1 -C 8 alkyl radical, or with carboxylic acids, soluble in the non-polar solvent, having the general formula: R 1 —COOH (2) wherein R 1 is an alkyl radical with a number of carbon atoms greater than or equal to 6, for example from 6 to 18; and/or b2. effecting a first coupling phase of the polymer chain with at least one halogen derivative selected from those having the general formula: R 4-y -M-X y (3) with X, M and R having the meaning defined above and y being an integer within the range of 2 to 4; and/or b3. effecting a second coupling phase with at least one aromatic derivative selected from those having the general formula: (R′) n —Ar (4) wherein R′ represents a C 2 -C 5 alkenyl radical, Ar a C 6 -C 18 aromatic radical, optionally substituted by a non-electron attractor group, whereas n is an integer ranging from 2 to 10; c. switching in batch the non-polar solvent with a vinyl aromatic monomer to yield a polymer solution based on butadiene; d. storing in tanks the polymer solution based on butadiene in a vinyl aromatic monomer, according to the polymer grade obtained; and e. feeding the polymer solution based on butadiene in the vinyl aromatic monomer, together with conventional polymerization additives and possibly a co-monomer, to a polymerization reactor, to produce a high impact vinyl aromatic(co)polymer by radical polymerization; and f. recovering the high impact vinyl aromatic (co)polymer from the polymerization reactor.