POLARIZATION PROPERTIES OF A NOVEL ORIENTED POLYDIACETYLENE

Polarized electronic absorption, Raman and luminescence spectra of gel -processed blends of a soluble polycarbazolyldiacetylene and ultrahigh molecular weight polyethylene are reported and compared with those ob served in other physical states. The films are oriented by tensile dra wing to a draw ratio of 62. The strong anisotropy of all the measured properties indicates a rather good orientation of the conjugated chain s along the stretching direction. The data here presented are quite di fferent from those described for other conjugated systems where the ge l-processed stretch-oriented polyethylene chains play an important rol e in the improvement of the order and in the enhancement of delocaliza tion for the conjugated guest. We attribute this peculiar behaviour to the stiffness of the conjugated skeleton. (C) 1998 Elsevier Science S .A. All rights reserved.