A bicontinuous structure in some systems with cubic mesophases

TL;DR

This paper investigates the formation of bicontinuous structures in cubic mesophases of polymer colloid complexes using literature analysis, modeling, energetic calculations, and comparison with experimental SAXS data.

Contribution

It introduces a combined approach of literature review, modeling, and energetic analysis to understand bicontinuous structures in cubic mesophases.

Findings

Bicontinuous structures are formed near the Lifshitz point due to phase transition changes.

A simple geometric model can estimate structure parameters and simulate scattering curves.

The phase transition shifts from second to first order in the presence of an effective field.

Abstract

A cubic structure of polymer colloid complexes is studied. The technique of the research includes i) an analysis of well-known literature SAXS data; on this base, at some assumptions, ii) constructing a simple model to estimate geometric structure parameters and to receive a simulated scattering curve, iii) calculations of energetic parameters by help of the analytical fluctuation theory of the phase transitions; iv) comparing the model with the real structure obtained from the SAXS data by the electron density distribution reconstruction method. In the presence of an effective field the 2-nd order phase transition transforms to the 1-st order one in the vicinity of the Lifshitz point. As a result, a bicontinuous structure in cubic mesophases is formed.