The characterization of orientation of poled polymer films with polarized IR spectra

Abstract

IR dichroism is one of powerful tool for studying orienting structure in polymer, the orientation of polymer films can be determined by the dichroic ratio R, which is related to the order parameter θ. The second order nonlinear coefficient d of poled polymer films can be estimated with the oriented gas model and Langevin function d 33 = 1 2 Nβ (ƒ 2ω)(ƒ ω) 2 〈cos 3θ〉 and 〈cos 3θ〉 = √0.6 θ . The d coefficients of poled films of (PS)O-DCV and P(NPPMA-MA) had been estimated and the values were reliable in order of magnitudes.