| Abstract: | The phase behaviour of gas-polymer-systems, which is important in the polymerization of gaseous monomers and in the separation of the polymers formed, was studied at a constnat temperature of 130°C and at pressures of 100–2000 bar. Dissolving polyethylenes of different average molecular weights in compressed ethylene, it was found, that the solubility of the polymer is decreased with increasing molecular weight of the polymer. The maximum in pressure of the phase-boundary curves increases and is shifted towards lower polymer concentrations. The analysis of the samples from the gas and the liquid phase showed that the average molecular weight as well as the molecular weight distribution of the polymer is different in the two phase and differs also from the polymer in the homogeneous mixture. The results were compared with the data of other authors. Furthermore it was tried to show with other systems. |
