(Macromolecules) Poly[(side-on mesogen)-alt-(end-on mesogen)]: A Compromised Molecular Arrangement
writer：Wang, M.; Bao, W.; Chang, W.; Chen, X.; Lin, B.; Yang, H.*; Chen, E.*
keywords：liquid crystal polymer
source：期刊
specific source：Macromolecules, 2019, 52, 5791-5800.
Issue time：2019年
In recent years, sequence-controlled
side-chain liquid crystal polymers (SCLCPs) have gained extensive
interests because mesogenic units with different lengths and distributions can
form various ordered sequences, which further endow LCP materials with diverse
functions. In this manuscript, a side-chain side-on maleimide-containing
monomer 2,5-bis-(4-butoxy-benzoyloxy)-benzoic acid
6-(2,5-dioxo-2,5-dihydro-pyrrol-1-yl)-hexyl ester (Y1801) and a side-chain end-on styrene-containing monomer 4''-[6-(4-vinyl-phenoxy)-hexyloxy]-biphenyl-4-carbonitrile
(Y1802) are combined in one single
macromolecular chain and orderly polymerized in an alternative
sequence, to form an alternating copolymer Poly(Y1801-alt-Y1802). The chemical structure
and alterative sequence of Poly(Y1801-alt-Y1802) are confirmed by GPC and
NMR techniques. The combination of DSC, POM and WAXS data indicates that
although the side-on homopolymer PY1801
and the end-on homopolymer PY1802
both exhibit nematic phase, their alternating copolymer Poly(Y1801-alt-Y1802)
shows an interdigitated smectic A phase, a compromised molecular arrangement
instead. In addition, a strong fluorescence emission of Poly(Y1801-alt-Y1802) is
observed, which might provide this novel alternating-structured liquid crystal
polymer with potential applications in luminescent materials and devices.