Semisolid preparations, rheology

Semisolid samples. As with liquid samples, methods (B) and (C) are the best choices for this type of sample. The specific choice will depend on fhe rheological properties (viscosity, density, air retention) of the particular preparation. These samples are best measured in the transflectance mode. Liquid and semisolid samples may contain a mixture of solvents of disparate volatility which may evaporate separately during the measurement process. Differences in solvent volatility can alter the sample matrix and lead to errors in the determination which are best avoided by using a set of calibration samples spanning an expanded range of solvent proportions. ... 

By blending the liquid and low melt polymers, semi-solid fluids with yield points, can be prepared that form dispersions. A imique balance of physical, fltermal and rheological properties was obtained, yielding fluids they can be administered as spreadable lotions, injectables or coatings for implantable or non-implantable devices. If properly designed and formulated, the fluids behave like semisolids that stay where they are placed, retain their shape and do not migrate like simple low viscosity liquids (Roller and Bezwada, 1996). 

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