Synthesis and physical properties of a main-chain chiral smectic thiol-ene oligomer

The synthesis and characterisation of a main-chain chiral smectic liquid crystalline thiol-ene polymer system is described. The chemical structure is designed based on the structure of W317, a mesogen with a large electroclinic effect in the Smectic A* (SmA*) phase. The novel thiol-ene monomer K0902 has a large surface electroclinic effect with an unexpected small electroclinic effect in the SmA* phase. The corresponding thiol-ene oligomer poly-K0902 is characterised by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), polarised optical microscopy (POM), X-ray diffraction (XRD) and shows an expected I-SmA*-Glass phase sequence, but the electroclinic angle is relatively small.