CHARACTERIZATION OF A NOVEL BLEND CONSISTING OF A LIQUID-CRYSTALLINE POLYMER AND A PHOTOPOLYMERIZED CROSS-LINKED ACRYLIC MATRIX

A blend of a novel soluble main chain liquid crystalline (LC) copolymer with a low molecular weight photopolymerizable trifunctional acrylate was formed. X-ray diffraction studies revealed that the structure of the mesophase was disrupted upon addition of the monomeric acrylates. However, once the blend was exposed to ultraviolet radiation and post-cured, a densely crosslinked semi-interpenetrating network of the second kind (semi-IPN-II) was formed, and the original structure of the mesophase was restored. The unique feature of this crosslinked blend is that the LC copolymer can undergo transitions from its LC to isotropic phase in the presence of the densely crosslinked acrylate matrix. In addition, this blend has mechanical integrity at temperatures well above the LC to isotropic transition region.