The production of rubber-modified polystyrene. Some criteria influencing the selection and design of the agitator system



The importance of selecting the most suitable form of agitation for the prepolymerization step in the production of rubber-modified polystyrene by a bulk polymerization procedure is related to the non-Newtonian behavior of the polymerizing system and to the existence of a minimum shear rate requirement. The procedure for the design and calibration of a small-scale reactor system is described which is shown to produce an adequate phase inversion of the prepolymer and from which data can be evaluated for any change in scale of the operation. Structural patterns in the final polymer are linked with average shear levels in the reactor.