Chiral dopants based on optically active (+)-2-methylbutan-1-ol were prepared. Two kinds of induced chiral nematic liquid crystal (N
*
-LC) were achieved by mixing the chiral dopants in 4-n-alkyl-4'-cyanobiphenyl (CBS) host nematic liquid crystal. The helical pitches of the N
*
-LC were measured and the regularities of change were analyzed. The results showed that the steric hindrance in the chiral region contributed to the helical twisting power (
) of the N
*
phase. The substitution between the two chiral center had a strongly effect on
and the temperature dependence of the helical pitch (d
p
/d
t
).
关键词
Keywords
references
Yang D K, Huang X Y,Zhu Y M. Bistable cholesteric reflective display : materials and drive schemes [J]. Annu. Rev. Mater. Sci., 1997, 27(1):117-146.[2] Yuan X T, Zhang L P, Yang H. Study of selectively reflecting characteristics of polymer stabilised chiral nematic liquid crystal films with a temperature-dependent pitch length [J]. Liquid Crystals, 2010, 37(4):445-451. [3] Yuan X T, Cao H, Yang Z, et al. A selective reflecting film with a temperature-dependent pitch length [J]. Chin. Chem. Lett., 2010, 21(3):279-282. [4] Lee H J, Jin Z X, Aleshin A N, et al. Dispersion and current-voltage characteristics of helical polyacetylene single fibers [J]. J. Am. Chem. Soc., 2004, 126 (51): 16722-16723.[5] Lee S W, Kim B, Lee D S, Lee H J, et al. Fabrication and mechanical properties of suspended one-dimensional polymer nanostructures: polypyrrole nanotube and helical polyacetylene nanofibre [J]. Nanotechnology, 2006, 17 (4):992-996. [6] Ofuji M, Takano Y, Houkawa Y, et al. Microscopic orientational order of polymer chains in helical polyacetylene thin films studied by confocal laser Raman microscopy [J]. J. Appl. Phys., 2006, 45 (1): 1710-1713.[7] Langeveld-Voss B M W, Janssen R A J. Christiaans M P T, et al. Circular dichroism and circular polarization of photoluminescence of highly ordered poly(3,4-di[(S)-2methylbutoxy] thiophene [J]. J. Am. Chem. Soc., 1996, 118 (20) : 4908-4909. [8] Peeters E, Christiaans M P T, Janssen R A J, et al. Circularly polarized electroluminescence from a polymer light-emitting diode [J]. J. Am. Chem. Soc., 1997, 119(41):9909-9910.[9] Bross P A, Schoberl U, Daub J. Carbohydrate modified conducting polymers: syntheses and electrochemistry of sugar linked azulenes and polyazulenes [J]. AdV. Mater., 1991, 3 (4) : 198-200. [10] Li W, Wang H L. Oligomer-assisted synthesis of chiral polyaniline nanofibers [J]. J. Am. Chem. Soc., 2004, 126 (8): 2278-2279. [11] Iwaura R, Hoeben F J M, Masuda M, et al. Molecular-level helical stack of a nucleotide-appended oligo(p-phenylenevinylene) directed by supramolecular self-Assembly with a complementary oligonucleotide as a template [J]. J. Am. Chem. Soc., 2006, 128(40):13298-13304.[12] Van Delden R A, Feringa B L. Color indicators of molecular chirality based on doped liquid crystals[J]. Angew. Chem., 2001, 40 (17): 3198-3200.[13] Gray G W, Hird M, Lacey D, et al. The synthesis and rarsition temperatures of some 4,4-dialkyl-and 4, 4-alkoxyalkyl-1,l':4', 1-terphenyls with 2,3-or 2', 3'-difluoro substituentsand of their biphenyl analogues[J]. J. Chem. Soc.Perkin Transactions, 1989, 2 (11):2041-2053.[14] Kuball H G, Bruning H. Helical twisting power and circular dichroism as chirality observations: the intramolecular and intermolecular chirality transfer[J]. Chirality, 1997, 9(5):407-423.[15] Shkolnikova N I, Kutulya L A, Pivnenko N S, et al. Relationship between the temperature dependence of the induced helical pitch and the anisometry of molecules of chiral dopants [J]. Liq. Cryst., 2005, 50 (6): 1084-1090.[16] Gottarelli G, Samori B, Stremmenos C, et al. Induction of cholesteric mesophases in nematic liquid crystals by some chiral aryl alkyl carbinols a quantitative investigation [J]. Tetrahedron, 1981, 37 (2) : 395-399.[17] Gottarelli G, Spada G. Induced cholesteric mesophases-origin and applications[J]. Mol. Cryst. Liq Cryst.,1985, 123 (4): 377-388.
Recent advances in data-driven research on liquid crystal materials
Advancements in the application of liquid crystal materials for information security
Liquid crystal microfluidic technology within microchannels and its applications
Progress on chiral photoswitches for constructing liquid crystal helical structures
Research progress on the motion control of liquid crystal solitons
Related Author
LIU jie
QI ji
GAO Shiyan
CHEN Wenyi
SUI Yuexin
HE Zemin
YANG Haiyan
MIAO Zongcheng
Related Institution
School of Artificial Intelligence, Optics and Electronics (iOPEN), Northwestern Polytechnical University
Key Laboratory of Liquid Crystal Polymers based Flexible Display Technology in National Petroleum and Chemical Industry, School of Electronic Information, Xijing University
Shaanxi Key Laboratory of Liquid Crystal Polymer Intelligent Display, Technological Institute of Materials & Energy Science (TIMES), Xijing University
Fujian College, University of Chinese Academy of Sciences
State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences