ABSTRACT
The analytical methodology of Field-Flow Fractionation (FFF) is a system of principles, practices, and procedures, the scope being to obtain required quantitative information on studied samples. Since samples of polymers and particles to be analyzed by FFF methods are not unknown in the majority of cases, the intention is to increase the level of knowledge on samples under analysis. Verification of the validity of a theory by means of a suitably selected experiment is very important. In the first place it must be confirmed whether mechanisms of FFF separation and accompanying phenomena assumed theoretically occur under real experimental conditions. The phenomena of secondary relaxation appear when the strength of the external physical field is programmed. These phenomena contribute to higher retention and zone dispersion values compared with theory. Optimization is generally aimed at making a system most effective.
