Solid state N.M.R. relaxation study of liquid crystal polymers employing a two dimensional technique

Molecular motions of liquid crystal polymers in the solid state cover a broad dynamic range, extending from the fast rotational to the ultra slow motional regime. Two dimensional N.M.R. relaxation spectroscopy is designed to follow these motions and to differentiate the various motional modes. In addition, different types of molecular order, modulated by these regions, are also discriminated. The solid state dynamics of the polyesters studied depends sensitively upon their thermal history. Annealed samples show a typical semicrystalline behaviour, manifested by two different motional components. The molecular order is characterized by a high degree of conformational and orientational order of the polymer chains, which is strongly correlated with the exceptional mechanical properties of these systems.