Comparison of Laboratory and Industrial Data on the Monomer Conversion during the Polymerisation of Isoprene

Abstract

The results of a comparative analysis of the kinetic relationships governing the polymerisation of isoprene in the presence of titanium and neodymium catalysts, obtained under laboratory conditions and on industrial units of an operating high-tonnage synthetic rubber plant, are set out. It is shown that the conversion curve for the polymerisation of isoprene in the presence of a neodymium catalyst hardly depends on the conditions of monomer solution preparation (laboratory or industrial conditions). Under conditions of industrial production over a titanium catalyst, the monomer solution is polymerised at a lower rate by comparison with an isoprene solution prepared under laboratory conditions, which is possibly due to the presence of isoamylenes. The polymerisation of isoprene in a cascade of three polymerisation reactors in the presence of a neodymium catalyst is characterised by a lower rate by comparison with synthesis conducted by a batch method in laboratory dilatometers. The synthesis of polyisoprene in the presence of a titanium catalyst in a cascade of two high-volume polymerisation reactors proceeds at a greater rate by comparison with laboratory conditions. Comparison of the polymerisation rate in this case is qualitative in nature, as the polymerisation temperature under laboratory conditions amounted to 20°C, while under industrial conditions, with adiabatic heating up of the reaction mixture, the temperature increased from 0 to 52°C for the neodymium catalyst and from −5 to 55°C for the titanium catalyst.