Demixing Kinetics of Phase Separated Polymer Solutions in Microgravity
The efficiency of particle separation in polymer two-phase systems appears to be up to several orders of magnitude lower than theoretical estimations based on Boltzmann statistics. To test the hypothesis that this inefficiency is at least partially due to the convection and sedimentation that occur during gravity-driven demixing we have begun a series of experiments aimed at characterising particle partitions in space. The one-g demixing of systems possessing equal densities has been studied. We have also studied the demixing of PEG/dextran systems in low gravity on KC-135 aircraft and during one Shuttle mid-deck experiment. The demixing rate data from these experiments have been analysed by two different approaches. In both cases the results are consistent with coalescence being a dominant feature of the gravity-free demixing process.
KeywordsInterfacial Tension Phase Droplet Phase Volume Ratio Phase Viscosity Boltzmann Equilibrium
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