US 11,795,259 B2
Methods for production of high impact polystyrene having an improved rubber morphology
Carlos de Anda, Pearland, TX (US); Giovanni Trimino, Houston, TX (US); Bradley Stiles, Houston, TX (US); and Jose Sosa, Deer Park, TX (US)
Assigned to FINA TECHNOLOGY, INC., Houston, TX (US)
Filed by FINA TECHNOLOGY, INC., Houston, TX (US)
Filed on Apr. 15, 2021, as Appl. No. 17/231,242.
Claims priority of provisional application 63/010,498, filed on Apr. 15, 2020.
Prior Publication US 2021/0324128 A1, Oct. 21, 2021
Int. Cl. C08F 279/02 (2006.01)
CPC C08F 279/02 (2013.01) 13 Claims
 
1. A process for producing high impact polystyrene comprising:
introducing to a first 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 first reactor to the phase inversion point to form a phase-inverted mixture;
recovering a portion of the phase-inverted mixture from the first reactor wherein the phase-inverted mixture comprises high impact polystyrene; and
introducing another portion of the phase-inverted mixture to another reactor wherein the another portion of the phase-inverted mixture comprises from about 1 volume percent (vol. %) to about 20 vol. % based on the total volume of the first reactor.