Effects of organomontmorillonite concentration on the structure formation of nanocomposites with 5CB liquid crystal

Organoclay-4-pentyl-4'-cyanobiphenyl (5CB) liquid crystal heterocomposites have been investigated using X-ray diffraction, IR-spectroscopy, polarizing optical microscopy (POM) and differential scanning calorimetry (DSC). Montmorillonite clay modified by dioctadecyldimethylammonium chloride was used as an inorganic component, and is hereinafter referred to as B3. Its concentration varied from 2 to 8 wt% in the composite materials. This modification of the clay results in a significant expansion of its interplanar spacing, into which 5CB dimers can penetrate during synthesis of the composite. It was found that the concentration dependence of the composite structure formation is dramatic. The most homogeneous system is formed at the clay concentration, C-B3=4.5%, as a result of Van der Waals interactions in this composite.