An analysis of the bulk polymerization of styrene by azobisisobutyronitrile in a tubular reactor was made. Rigorous models were developed and verified. A diffusion model gave predictions of molecular weights and conversions that were 2% higher on the average than the experimental values. Another model, a plug flow contraction of the diffusion model, predicted molecular weights and conversions that were 6% higher on the average than the experimental values.
The diffusion model showed that optimal conversions could be obtained by proper reactor operation. Tentative studies for optimal conversion with minimal molecular weight dispersion indicated the reactor should be operated at a wall temperature 5° to 10°C below that required for optimal conversion.