Diphenyltriacetylenes: novel nematic liquid crystal materials and analysis of their nematic phase-transition and birefringence behaviours
作者:Yuki Arakawa、Sungmin Kang、Shunpei Nakajima、Koichi Sakajiri、Yokan Cho、Susumu Kawauchi、Junji Watanabe、Gen-ichi Konishi
DOI:10.1039/c3tc31658k
日期:——
Improvements in birefringence properties of LC materials are actively being pursued because of the increase in their applications in optical devices. 1,6-Diphenyl-1,3,5-hexatriyne, i.e., diphenyltriacetylenes (DPTAs; number of acetylene units, n = 3) are expected to have wide nematic mesophases and exhibit extremely high birefringence properties because of the high aspect ratio of their conjugated
由于液晶材料在光学装置中的应用增加,因此积极地追求液晶材料的双折射特性的改善。1,6-二苯基-1,3,5-己三炔,即二苯基三乙炔(DPTA;乙炔单元的数量,n = 3)具有宽的向列中间相,并且由于它们的高长宽比而表现出极高的双折射特性。共轭结构。因此,我们合成了DPTA衍生物,作为新型的高双折射向列型液晶材料。所述衍生物表现出具有更长的烷氧基碳链长度的稳定的对映向列相(即,具有十二烷氧基,m= 12)。高双折射值Δn对于三炔DPTA-OC6,在550 nm和140°C时= 0.46,并且具有超过2.0的高非凡折射率(n e)。此外,我们研究了乙炔键对具有两个末端芳香环的共轭低聚炔或聚炔化合物的向列转变行为和折射率参数的影响。乙炔单元数量的增加(n = 1-3),即延长的共轭,导致更宽的向列相和更高的双折射。每个乙炔单元的Δn增量估计约为0.14。