Bulk High-Impact Polystyrene Process, 1. Partitions of tert-Butyl Peroctoate and Styrene in Blends Containing Polystyrene and a Rubber

CARLA V. LUCIANI; DIANA A. ESTENOZ; GREGORIO R. MEIRA; NANCY L. GARCÍA; HAYDÉE M. OLIVA

MACROMOLECULAR THEORY AND SIMULATIONS

WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Año: 2007 vol. 16 p. 703 - 710

1022-1344

In relation to the bulk high-impact polystyrene process, this work investigates the partition  between phases of styrene and an initiator: tert-butyl peroctoate. A Flory-Huggins model was applied for predicting the phase separation point and the partitions of styrene and tert-butyl peroctoate. For blends of styrene, polystyrene, and a styrene-butadiene diblock copolymer, the model provides reasonable predictions of a ternary equilibrium diagram. For blends of styrene, polystyrene, polybutadiene, and tert-butyl peroctoate, the partition of tert-butyl peroctoate was measured at 25 8C. At emulated conversions of 13% or lower, equilibrium was reached after 1 h of mixing time. For the higher molar masses and conversion of 16%, equilibrium was not reached after 24 h of mixing time. To fit the equilibrium measurements, the solubility parameter of tert-butyl peroctoate was adjusted.tert-butyl peroctoate. A Flory-Huggins model was applied for predicting the phase separation point and the partitions of styrene and tert-butyl peroctoate. For blends of styrene, polystyrene, and a styrene-butadiene diblock copolymer, the model provides reasonable predictions of a ternary equilibrium diagram. For blends of styrene, polystyrene, polybutadiene, and tert-butyl peroctoate, the partition of tert-butyl peroctoate was measured at 25 8C. At emulated conversions of 13% or lower, equilibrium was reached after 1 h of mixing time. For the higher molar masses and conversion of 16%, equilibrium was not reached after 24 h of mixing time. To fit the equilibrium measurements, the solubility parameter of tert-butyl peroctoate was adjusted.