Barrier properties of light-induced ordered phase and thermo-induced ordered phase of azobenzene containing side-chain liquid crystalline polymers were investigated by a ferrous matrix surface oxidation method.Different mesogen distributions were obtained by linear polarized light irradiation and by annealing the as-cast film

and were characterized by polarized light microscopy (POM) under conoscopic observation.Upon a 473 nm linear polarized light irradiation

an interference figure was observed suggesting the formation of an in-plane arranged single-domain ordered phase.In contrast

the thermo-induced polydomain liquid crystalline(LC) phase showed a bright field vision when the sample was annealled at a temperature below its clear transition point

suggesting the formation of a randomly orientated multi-domain LC phase.Their permeation rates were obtained by measuring the surface oxidation rate of the ferrous matrix covered with differently arranged liquid crystalline polymer films.It was found that the barrier value of the orientated film was 2.5 times higher than those of the amorphous film

and about 1.25 times higher than that of the thermotropic liquid crystalline phase.Combining the conoscopic observation results

the gas permeation behavior in the liquid crystalline polymer films was proposed.Linear polarized light induced mesogens orientation and assembled a single-domain order phase

which eliminated the permeable boundary existed in the thermotropic polydomain liquid crystalline phase.Thus

the low value of permeability was attributed to a low diffusion coefficient in the ordered phase.