Free-radical solution polymerization of styrene in a tubular reactor - Effects of recycling

The styrene free-radical solution polymerization reaction in a tubular loop reactor is studied here both experimentally and through simulation. An attempt is made to compare the performances of tubular loop reactors when the recycle ratio is varied. based on steady-state and dynamic responses and on the quality of the polymer produced at different conditions. It is shown here that steady-state responses of loop reactors and traditional tubular reactors are very similar as far as the quality of the polymer obtained is concerned. Therefore, the recycle ratio cannot be used as a fundamental operation parameter for grade transitions at plant site. However, it is also shown that the recycling of polymer material is very important to accelerate the attainment of the final steady-state in tubular reactor configurations, because recirculation of material homogenizes the distorted radial profiles of the axial flow velocities.