Synthesis and Liquid Crystalline Studies of 2,4-bis(4'-n-nonyloxybenzoyloxy)benzylidene-4''-n-alkoxyaniline

Wali M. Hamad; Shalaw K. Salih

doi:10.14500/aro.10210

Wali M. Hamad Department of Chemistry, Faculty of Science and Health, Koya University, Daniel Mitterrand Boulevard, Koya KOY45, Kurdistan Region
Shalaw K. Salih Department of Chemistry, Faculty of Science and Health, Koya University, Daniel Mitterrand Boulevard, Koya KOY45, Kurdistan Region http://orcid.org/0000-0002-9951-2422

Keywords: Liquid Crystals, Schiff basses, Nematic, Smectic.

Abstract

In this paper, a series of new Schiff-bases: 2,4-bis(4’‑n‑nonyloxy -benzoyloxy)benzylidene-4’’-n-alkyloxyaniline (DC9An) were synthesized. The characterization of compounds was achieved through using (ultra violet, infrared, ¹H-nuclear magnetic resonance) measurements. This series comprises 10 members differ by the length of n-alkoxy chain (i.e., OC_nH_2n+1, n=1-10). Their liquid crystalline properties were studied using differential scanning calorimetry and polarizing optical microscopy. The lower series such as n=1-3 are purely nematogenic liquid crystals, but the other means (n=4-7) have nematic and smectic phases (S_mC and S_mA). The higher members (n=8-10) are purely smectogenic liquid crystals.

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Author Biographies

Wali M. Hamad, Department of Chemistry, Faculty of Science and Health, Koya University, Daniel Mitterrand Boulevard, Koya KOY45, Kurdistan Region

Dr. Wali M. Hamad is Assistant Professor and President of Koya University since Feb 2015 and the Executive Publisher of Aro. He got his Ph.D. degree in the field of physical chemistry (Liquid crystal) at the University of Baghdad in 2001. He has served as dean of the Koya Technical Institute from May 2004 to November 2010. Dr Weli led at the same time the Department of Oil Refinery for one year. He also actively worked for establishing the College of sscience of the Koya university. Dr. Hamad is an active member of the Teacher Federation and the Physics and Chemistry Society of Kurdistan. He has a number of scientific articles and books in the field of physical chemistry, and advanced thermodynamics as well as in fields of cultural science and politics which appeared in numerous peer-reviewed national and international journals and magazines. In addition, he has presented in numerous internationally peer reviewed conferences. (see TAP). [e-mail: wali.hamad@koyauniversity.org]

Shalaw K. Salih, Department of Chemistry, Faculty of Science and Health, Koya University, Daniel Mitterrand Boulevard, Koya KOY45, Kurdistan Region

Mr. Salih got his M.Sc. degree in Physical Chemistry. Recently, he is an Assistant Lecturer at the Department of Chemistry, Faculty of Science and Health, Koya University. [see TAP]

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