Comparative study of mixed monolayers of a calixarene with a fatty acid and a non-amphiphilic nematic liquid crystal

Many nematic liquid crystals (NLCs) lack a polar headgroup and thus are not able to form stable monolayers at the air/water (a/w) interface. A way to obtain monomolecular films of these compounds is to incorporate them into h ost monolayers of amphiphilic molecules. We report a comparative investigat ion of mixed films of Calix[4]resorcinarene O-octacar-boxymethylated (CRO) with the non-amphiphilic NLC MBBA and with the amphiphilic stearic acid (SA ). The comparative study is useful for a better understanding of the charac teristics of the CRO-MBBA mixed films. Surface-pressure and surface-potenti al measurements on the monolayers at a/w interface, as well as ellipsometri c and spectroscopic measurements on transferred Langmuir-Blodgett (LB) film s, confirm that MBBA is additively incorporated into CRO films.