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Thermoreversible helical fibers from photoreactive triphenylene-derived liquid crystals in liquid paraffin.

ABSTRACT: Liquid crystalline triphenylene derivatives, TPC1_p-n (n = 6, 12, 14, 16) were prepared using p-alkoxycinnamate as the [2+2] photo-cyclization site. TPC1_p-n (n = 12, 14, 16) showed Col_r phase and gave crescent-shaped or helical fibers after UV-irradiated in liquid paraffin solutions at 90 and 110 °C in the Col_r temperature range. The apparent photoreaction products were shown to be thermally reversible, i.e. they dissolved in liquid paraffin at high temperatures and reappeared on cooling, indicating that they were aggregates of oligomerized TPC1_p-n. The reaction mechanism was discussed in terms of the structure of the liquid crystalline phase.

SUBMITTER: Hirose T

PROVIDER: S-EPMC10694167 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature

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Thermoreversible helical fibers from photoreactive triphenylene-derived liquid crystals in liquid paraffin.

Hirose Takuji T Kikuchi Yuka Y Nakano Tomoaki T Ohno Tsukasa T Kawamura Kengo K Nazri Normazliana Binti NB Fujimori Atsuhiro A Kodama Koichi K Yasutake Mikio M

Heliyon 20231110 11

Liquid crystalline triphenylene derivatives, TPC1p-n (n = 6, 12, 14, 16) were prepared using p-alkoxycinnamate as the [2+2] photo-cyclization site. TPC1p-n (n = 12, 14, 16) showed Colr phase and gave crescent-shaped or helical fibers after UV-irradiated in liquid paraffin solutions at 90 and 110 °C in the Colr temperature range. The apparent photoreaction products were shown to be thermally ...[more]

PMID: 38053870

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