Poly(4-vinyl pyridine)/zinc dodecyl benzene sulfonate mesomorphic state due to coordination complexation

Recently, it has been shown that the properties of flexible and semi-rigid polyelectrolytes can be tailored by using specific surfactants. In these cases, mesomorphic structures in bulk and in solution and network. morphologies in blends have been achieved. In polyelectrolytes, the available electrostatic interaction to bond the surfactants is large due to the charges bound to the polymer backbone. In this work, we show that mesomorphic behavior of even noncharged flexible polymers can be achieved if the interaction between the polymer and the surfactant is selected properly. The model system is atactic poly(4-vinyl pyridine) (P4VP) in combination with zinc dodecyl benzene sulfonate (Zn(DBS)(2)). FTIR measurements indicate that transition metal coordination between the Zn cation and the pyridine amines takes place, SAXS and birefringence show that mesomorphic structures are obtained, the long period being 27.8 Angstrom in the nominally fully complexed case and 26.1 Angstrom when the degree of complexation is 25%. Also pure Zn(DBS)(2) is mesomorphic with the long period of 23.7 Angstrom. The difference between the layer thicknesses of Zn(DBS)(2) and P4VP(Zn(DBS)(2))(x) can be explained by the atacticity of the polymer.