Investigation of the pressure dependency of phase equilibria in colloidal model systems

摘要: In this thesis the experimental studies of pressure jumps effect on several systems, representing a cross-section soft matter materials. The phase behaviour colloidal dispersions and polymeric micellar solutions using temperature as variables are presented in first part. second part addresses correlation between dependency polymer viscosity diffusion time nanoscopic probe dissolved polymer. As subject-matter, interplay between percolation separation appearing an adhesive hard sphere (AHS) system, represented by octadecyl coated silica particles toluene, is discussed. transitions to percolated biphasic states obtained they agreement with theoretical predictions. For concentrations higher than around 12-14vol%, increase the forward scattering intensity found be governed proximity spinodal line. But it that controls scale at which scattering increases. lower two approaches determine line were proposed. Depending way determination system expected undergo separation either through nucleation or decomposition process. scenario sample starts reveal non-ergodic while forming nuclei (the denser phase), lies below line phase diagram. latter expected lie binodal and lines, decomposing, volume spanning network formed, gives rise attributed state. This study competition addressed time-resolved measurement. next chapter temperature- pressure-dependent water water-DMF micelles composed poly(ethylene-copropylene- b-(ethylene oxide)) (PEP-PEO) block copolymer described. It that radius gyration for solution decreases approaching critical (LCST), increasing temperature pressure. However, dispersion there no change radius 4 until sets in. case applying has similar as (although simple linear dP/dT relation), acts lowering temperature. last dependence rubrene poly(ethylene-co-propylene) (PEP) melt investigated fluorescence spectroscopy. Its polymer found. proof changes varying solely due variation PEP viscosity.