1990 Volume 23 Issue 3 Pages 290-296
The emulsion polymerization of styrene in a continuous-loop tubular reactor (CLTR) is studied as functions of the soap concentration and temperature. The soap concentrations of sodium lauryl sulfate (SLS) ranged from 3.73 to 24.24 g/l-water, and reaction temperatures ranged from 50 to 70°C are examined. The effects of temperature and soap concentration on the conversion, average diameter of particles, number concentration of particles and average molecular weight are discussed. It is found that instability of monomer conversion and the number concentration of particles during the polymerization are the overshoot but not oscillation or multiple steady states. The phenomenon of monomer conversion is eliminated by adjusting the soap concentration. The reaction mechanism of the polymerization in the case of low soap concentration (3.73 g SLS/l-water) is different from that with a soap concentration higher than 12.40 g SLS/l-water.