Rheological Study Involving Blends of Styrene, Polystyrene, and Polybutadiene. Application in the Bulk Polymerization Process for the Synthesis of High-Impact Polystyrene

LUCIANI, C. V.; ESTENOZ, D. A.; DIAZ DE LEÓN, R.; MORALES, G.; MEIRA, G. R.

Mar del Plata, Argentina

Jornada; Jornadas SAM/CONAMET 2005 - MEMAT 2005; 2005

The rheological behavior of polystyrene-polybutadiene blends with and without styrene and compatibilizing agents (diblock copolymers) was experimental and theoretically investigated. The following samples were prepared: a) 52 blends of polystyrene-polybutadiene-diblock copolymer, with polystyrene volume fractions varying between 5% and 55%; and b) 24 blends of polystyrene-polybutadiene-diblock copolymer-styrene with emulated conversions between 10 and 50%. For all of these samples, their shear viscosities-shear rate functions were determined. The measurements were compared with the predictions, and in general a good agreement was observed. For the blends that included styrene, the developed model is potentially applicable for estimating the phase inversion period in the bulk polymerization process for the production of high-impact polystyrene (HIPS). For polymers blends that did not include the monomer, the model could help to describe the behavior of a HIPS melt together with its Melt Flow Index. Keywords: High-Impact Polystyrene, Viscosity, Phase Inversion, Melt.