NOVEL STUDY ON THE LIQUID-CRYSTALLINE BEHAVIOR OF POLY(METHACRYLATE)SWITH BIPHENYL SIDE-GROUPS

We report the synthesis and characterization of a series of liquid cry stalline polymers substituted with the 4'-methoxybiphenyl-4-yloxy grou p. The spacer length is varied from 4-8 methylene units. The materials are characterized by polarized light microscopy, differential scannin g calorimetry, and X-ray analysis. All homologues show highly ordered phases. Additionally, the butylene polymer shows a broad nematic mesop hase. For the first time, the narrow nematic phase of the hexylene hom ologue could be confirmed experimentally. m-ray analysis of the polyme rs made exact assignments of the low temperature phases possible, thus giving access to the analysis of the arrangement of the mesogenes wit hin the layers. The pentylene homologue shows a distinct deviation fro m the behavior of the other polymers. (C) 1998 John Wiley & Sons, Inc.