VERFAHREN ZUR HERSTELLUNG VON HOMOPOLYMERISATEN ODER COPOLYMERISATEN DES PROPYLENS

For producing homopolymers or copolymers of propylene in the gas phase, gaseous or liquid monomers are introduced into a polymerization zone; the pressure and temperature in the polymerization zone are kept within a range that corresponds to the gaseous state of the monomers; gaseous monomers not consumed by polymerization are discharged from the polymerization zone and liquefied and re-introduced in liquid form into the polymerization zone. The temperature regulation in the polymerization zone is done by means of continuous measurement of the temperature and a change, tripped upon a change in temperature, in the quantity of liquid monomers introduced per unit of time into the reaction zone. To that end, the temperature is measured at a plurality of points vertically offset from one another, and from the respective measured values a respective mean value is formed. The mean values are compared with computed set-point value specifications, and if there are deviations, the quantity of monomers to be fed into the polymerization zone is changed accordingly.