02761nas a2200253   4500008004100000245011300041210006900154260000800223300001400231490000600245520182500251653001602076653001802092653003802110653002502148653003202173653002502205653004502230653003202275653001702307653003302324100001902357856013102376       2011                        eng d00aSynthesis and characterization of cholesteric thermotropic liquid crystalline polyesters based on isosorbide0 aSynthesis and characterization of cholesteric thermotropic liqui  cOCT  a1520-15270 v23 a<p>Generally main chain cholesteric thermotropic liquid crystalline polymers are prepared form chiral dia-cid or diol monomer. But these monomers are costly. Isosorbide is chiral cycloaliphatic diol accessible from renewable resources in the form of pure enantiomers. Thus it is used to synthesize main chain cholesteric thermotropic liquid crystalline polymers. Incorporation of phenyl hydroquinone into the backbone of the main chain frustrates chain pack-ing, thus lowering the crystallinity and depressing the melting point below the degradation temperature, also improves the solubility due to disruption of packing and maintains the mechanical and thermal performance. Results: Optical microscopy study reveals that more than 50% of isosorbide content with phenyl hydroquinone and terephthalic acid showed “yellow iridescent oily streaks” with a background of mosaic/marble texture. These are the typical textures of cholesteric liquid crystalline phase. Copolyesters based on phenyl hydroquinone, isosorbide and terephthalic acid are soluble in aprotic solvents like N,N-dimethylacetamide (DMAC), dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), and N-methyl-2-pyrrolidone (NMP). Solubility increases with the content of isosorbide percent. Thermal stabil-ity of all copolyesters was more than 300˚C on the basis of 10 wt% loss. Conclusions: It was found that main chain cholesteric thermotropic liquid crystalline polymers can be prepared form chiral cycloaliphatic diol such as isosorbide. Main chain cholesteric thermotropic liquid crystalline polyesters are prepared from phenyl hydroquinone, isosorbide and terephthalic acid showed thermal stability more than 300˚C. Main chain cholesteric thermotropic liquid crystalline polymers are soluble in aprotic solvents like DMAC, DMSO, DMF and NMP</p>10aCholesteric10aCrystallinity10adifferential scanning calorimetry10aInherent   Viscosity10aLiquid Crystalline Polymers10aOptical   Microscopy10aSolubility and Solution Polycondensation10aThermo Gravimetric Analysis10athermotropic10aWide Angle X-Ray Diffraction1 aChavan, Nayaku  uhttps://library.ncl.res.in/content/synthesis-and-characterization-cholesteric-thermotropic-liquid-crystalline-polyesters-based