Synthesis and mesomorphic properties of novel multi-arm side-chain liquid crystal polymers with different terminal substituents.

In this study, two novel aromatic ester multi-arm liquid crystal monomers M1 and M2 with different terminal substituents centred on 3,4,5-trihydroxybenzoic acid, and a rod-shaped chiral liquid crystal monomer N were designed and synthesised. The synthesised liquid crystal monomers M and N were grafted and copolymerised with polymethylhydrosiloxane (PMHS). The structural characterisation of the synthesised liquid crystal compounds was carried out by FT-IR and 1H-NMR. The mesomorphic properties of the synthesised liquid crystal compounds were characterised by POM and DSC, and the results showed that the multi-arm liquid crystal monomers M1 and M2 are typical enantiotropic nematic liquid crystal compounds and N is typical thermotropic enantiotropic cholesteric liquid crystal. Polymers P1 and P2 are both cholesteric liquid crystal polymers. The glass transition temperatures and liquid crystal isotropic transition temperatures of polymers P1 and P2 series both tend to increase with the increase of multi-arm liquid crystal monomer M. [ABSTRACT FROM AUTHOR]