Centrifugal gravity for polymer characteristics and phase separation

Low shear-rate viscosity measurements of a fluid in a closed system tend to exclude the standard viscometers because of the difficulty involved in isolating the moving components of such instruments from the sample chamber. Yet, there is a need to develop instruments which permit isolation of the sample chamber especially when the fluid of interest is carcinogenic and/or susceptible to interaction with the external environment. Phase separation of polymer blends an interesting topic for researchers to study extensively theoretically and experimentally for many decades. Polymer phase separation has a morphology of dot, line or bi-continuous shape. Application of this phase separation morphology is used for many potential applications such as photovoltaic devices, light-emitting diodes, antireflection coatings and biological devices. Moreover, a new phase-change material might be found to have the best germanium, antimony and tellurium (Ge-Sb-Te) alloy. The goal was to find the best contrast between the crystalline and amorphous states and they are used for electronic device memory either DRAM or Flash chips finally. For polymer solutions, many approaches and techniques have been used to determine the coexistence curve including the lower critical solution temperature (LCST) and the upper critical solution temperature (UCST). A modified centrifugal apparatus for measuring the coexistence curves of a polymer solution: polystyrene solution in methyl cyclohexane is reported for the first time in research laboratory.