Abstract: A styrenic polymer characterized by a z-average molecular weight of from about 339 kDa to about 520 kDa; a molecular weight distribution of from about 2.5 to about 5.0; a melt strength of from about 0.010 N to about 0.018 N and a melt A method of preparing a styrenic polymer comprising contacting a styrenic monomer, an optional comonomer and an optional initiator to a plurality of temperature environments wherein the difference in temperature between the first environment and the last environment is greater than about 30° C. to form the styrenic polymer; and recovering the styrenic polymer.

Abstract: A high impact polystyrene reactor system includes a first continuously stirred tank reactor. The first continuously stirred tank reactor includes an inlet configured to receive (i) at least one vinyl aromatic monomer, (ii) an elastomer, and (iii) a free radical initiator; and an outlet configured to convey a first reactor effluent. In addition, the high impact polystyrene reactor system includes a second continuously stirred tank reactor. The second continuously stirred tank reactor includes an inlet in fluid communication with the first continuously stirred tank reactor outlet and configured to receive (i) a portion of the first reactor effluent from the first continuously stirred tank reactor, (ii) at least one vinyl aromatic monomer, (iii) an elastomer, and (iv) a free radical initiator; and an outlet configured to convey a portion of a second reactor effluent comprising high impact polystyrene.

Abstract: A process for producing high impact polystyrene comprising introducing to a reactor a partially-polymerized mixture comprising at least one vinyl aromatic monomer, an elastomer and reacted vinyl aromatic monomer wherein the partially-polymerized mixture has not undergone phase inversion; polymerizing the partially-polymerized mixture in the reactor to the phase inversion point to form a phase-inverted mixture; recovering a portion of the phase-inverted mixture from the reactor wherein the phase-inverted mixture comprises high impact polystyrene; and introducing another portion of the phase-inverted mixture to another reactor.

Abstract: A process for producing high impact polystyrene comprising introducing to a reactor a partially-polymerized mixture comprising at least one vinyl aromatic monomer, an elastomer and reacted vinyl aromatic monomer wherein the partially-polymerized mixture has not undergone phase inversion; polymerizing the partially-polymerized mixture in the reactor to the phase inversion point to form a phase-inverted mixture; recovering a portion of the phase-inverted mixture from the reactor wherein the phase-inverted mixture comprises high impact polystyrene; and introducing another portion of the phase-inverted mixture to another reactor.