Über die Auswahl von Polymerisationsreaktoren

Choice of polymerization reactors . Industrial syntheses of polymers always yield a highly complex product whose adequate characterization often requires application-oriented tests in addition to chemical and physical parameters. In contrast to the synthesis of low-molecular mass substances subsequent corrections, e. g. by distillation or crystallization, are usually impossible. Extremely detailed reaction control is of paramount importance. Polyreactions can be classified according to kinetic aspects (monomer linkage with and without termination reaction, linkage of polymers). Apart from homogeneous bulk polymerization, there are the heterogeneous processes of precipitation-, bead-, and emulsion-polymerization. The polymerization reactors can be assigned to the known ideal types (batch reactor, continuous plug flow reactor, series of stirred tanks, and continuous stirred tank reactor). High viscosity often thwarts thorough mixing in bulk polymerization and segregation may occur. The article surveys the variants of the reactor types used for various polyreactions and polymerization processes in industry and examines the reasons for this choice. Most commonly used is the batch reactor, followed by the cascade of stirred tanks. Continuous polymer-linkage (polycondensation, polyaddition) is frequently performed in a series of several different kinds of reactors.