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

ABSTRACT

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.

GRAPHICAL ABSTRACT

KEYWORDS:

• Multi-arm
• ester
• liquid crystal polymers
• cholesteric
• synthesis

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was financially supported by the Fundamental Research Fund for the Central Universities [N180705004].