LAUSR

To realize advanced electrical applications for ferroelectric liquid crystalline polymers, high spontaneous polarization (Ps ) is highly desired. However, current ferroelectric liquid crystalline polymers usually exhibit a low Ps . In this work, we designed and synthesized mesogen-free, chiral polyethers containing sulfonylated methyl-branched alkyl side chains with a -(CH2 )3 O- spacer between the sulfonyl and the branched alkyl groups. In contrast to the linear n-alkyl side chains, the methyl-branched alkyl side chains induced chain tilting in the smectic layers. When double chirality existed in both the main chain and the side chains, a crystalline structure was observed after mechanical stretching. Intriguingly, when single chirality existed in either the backbone or the side chains, a liquid crystalline smectic C phase was obtained. The electric displacement-electric field study, however, did not show typical ferroelectric switching, although the dielectric constants were relatively high for these liquid crystalline polymers. This is likely because the dipole-dipole interactions among neighboring sulfonyl groups along the main chain were so strong that the ferroelectric switching was hindered in the samples. For the future work, it is desired to weaken the dipole-dipole interaction to achieve ferroelectricity in these mesogen-free liquid crystalline polymers. This article is protected by copyright. All rights reserved.