Abstract:
It is shown that a more than significant amount of experimental data obtained in the field
of studying systems based on thermosensitive hydrophilic polymers and reflected in the literature
over the past decades makes the issue of their systematization and classification relevant. This, in
turn, makes relevant the question of choosing the appropriate classification criteria. It is shown that
the basic classification feature can be the number of phase transition stages, which can vary from
one to four or more depending on the nature of the temperature-sensitive system. In this work,
the method of inverse phase portraits is proposed for the first time. It was intended, among other
things, to identify the number of phase transition stages. Moreover, the accuracy of this method
significantly exceeds the accuracy of the previously used method of direct phase portraits since, for
the first time, the operation of numerical differentiation is replaced by the operation of numerical
integration. A specific example of the application of the proposed method for the analysis of a
previously studied temperature-sensitive system is presented. It is shown that this method also
allows for a quantitative comparison between the results obtained by the differential calorimetry
method and the turbidimetry method. Issues related to increasing the resolution of the method of
direct phase portraits are discussed.
