Electrical determination of the degree of cross-linking in a poled non-linear optical polymer

A comparative investigation of the thermal dipole-orientation stability in a guest-host and a cross-linked non-linear optical polymer with similar structures of the polymer backbone is reported. Cross-linking yields a rigid polymer network with two types of dipoles: those already cross-linked and therefore thermally stable and those not as yet cross-linked and therefore fast relaxing. The combination of isothermal and thermally stimulated measurements allows for a complete characterization of dipole relaxation in the two sample polymers.