Photocrosslinkable liquid crystalline polymers based on cyclohexanone and fluorescent heterocyclic ring system

New liquid crystalline polymers containing both fluorescent and photocrosslinking properties with various alkyl chain lengths (m=2,4,6,8,10) were prepared by solution polycondensation reaction of 2,6-bis[4-(m-alkoxy)benzylidene] cyclohexanone and (4- phenyl)-2,6-bis (4-chlorocarbonyl phenyl) pyridine in THF using triethylamine as an acid acceptor. The polymers were characterized using various spectral techniques. These polymers were found to be thermally stable up to 377 degrees C confirmed by thermogravimetric analysis (TGA). Differential scanning Calorimetry (DSC) and polarized optical microscopy (POM) were carried out to study the phase structures and phase behaviors of this series of polymer. Some of the polymers with longer methylene chains demonstrated grainy type nematic LC phases. On irradiation with UV light at various time intervals, the prepared polymers showed different rate of crosslinking depending upon the alkyl chain lengths present in the polymer backbone. In addition, these polymers also show enhanced fluorescent property by the presence of heterocyclic unit in the polymer.