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Supramolecular side-chain liquid crystalline poly(acrylate)s have been prepared by self-assembly of H-bond donor and acceptor complexes through intermolecular complementary hydrogen bond formation. Poly[4-(m-acryloyloxyalkyloxy)benzoic acid]s [m = 6 (P1) and 8 (P2)] were employed as polymer components. Liquid crystalline nicotinic acid derivatives (C1, C2, C3, and C4) were used as complementary H-bond donor/acceptor counterparts. The liquid crystalline properties of the nicotinic acid derivatives, the polymers and their complexes were investigated by DSC and POM. Methylene spacers present at the terminal position of the nicotinic acid derivatives played a key role in mesophase arrangements. The columnar phase exhibited by the nicotinic acid derivatives completely disappeared in the H-bonded complexes to afford a nematic phase, thereby substantiating the complex formation.

Two series of heterocyclic liquid crystalline compounds with [1,2,3]-triazole ring at the terminal position were synthesized and analyzed for mesomorphic properties and its characteristics. Heterocyclic triazole core was introduced in to the target compound through click reaction between aromatic phenolic azide and alkyl propargyl ethers. The structure of the target compounds and intermediates was conformed by the 1 H NMR, 13 C NMR and IR spectral techniques. All the compounds in both the series were exhibited thermotropic liquid crystalline mesophase. These compounds show enantiotropic Smectic A phase on heating and cooling experiments. This was further confirmed using differential scanning calorimetric investigations. Interestingly, earlier reports on non-polar alkyl group attached to [1,2,3]-triazole heterocyclic ring was not showing any liquid crystalline properties but in the present investigation introduction of polar alkoxy group very near to [1,2,3]-triazole heterocyclic ring displayed liquid crystalline properties.

Three series of side chain liquid crystalline polymers containing terminally substituted biphenyl cinnamoyl esters were synthesized and characterized. The para position in the cinnamoyl group was connected with polymer backbone through various even numbers of methylene spacers. The terminal electron acceptor and donor substituted biphenyl groups were linked to cinnamoyl group through ester linkages. Polarizing microscopic and DSC studies confirm the formation of thermotropic mesophase up on heating. All the polymers exhibited nematic/grainy mesophases. The TGA and DSC studies showed that the nature of the terminal substituents have significant effect on mesophase temperatures as well as in thermal stability of these liquid crystalline polymers. UV light promoted photocrosslinking studies reveal that the clear involvement on photocrosslinking efficiency, although they are linked to the olefinic bond of cinnamoyl group through their ester linkage. It is observed that electron-donating group accelerate the photocrosslinking rate, while acceptor group retard the phase of the reaction on the other hand, the unsubstituted polymers show an intermediate rate.