Nanoscale segregation, molecular recognition and fluorophobic effect - from molecular design towards complex mesophase morphologies

Mesomorphic structure formation of hydrogen-bonded complexes of amino substituted 1,3,5-triazines with complementary (semiperfluoro)alkoxybenzoic acids is presented. The substitution pattern of both components was modified systematically in order to elucidate the influence of molecular parameters on the mesophase morphologies of the binary mixed systems. The phase sequence of the triazines, and of their associates with the acids, spans the range from smectic layer structures to discontinuous cubic phases composed of closed inverted micelles. Columnar phases with various two-dimensional lattice symmetries and bicontinuous cubic phases were found as intermediates. The mesophase morphologies are discussed in terms of the microsegregation of rigid polar, lipophilic and fluorinated molecular blocks in different sub-spaces along with tailoring the shape of (curved) aggregates by the space requirement of incompatible molecular fragments.