PREDICTION OF THE MOLECULAR-WEIGHT OF POLYETHYLENE PRODUCED IN A SEMIBATCH SLURRY REACTOR BY COMPUTER-SIMULATION

For polyethylene produced over Ziegler-Natta catalysts in a semibatch slurry reactor, a kinetic model was used to predict molecular weight a nd polydispersity. A computer simulation on molecular weight and polyd ispersity was carried out with the changes of chain-transfer rate cons tants (k(trm), k(trh), and K-tra) and initiation rate constant (K-i). The effects of monomer concentration, aluminum alkyl concentration, hy drogen concentration, and temperature on molecular weight and polydisp ersity with respect to polymerization time were investigated.