Dynamical Molecular Conformation and Structure of Cluster for Saturated and Unsaturated Fatty Acids in the Liquid State

• Project/Area Number: 10640566
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 機能・物性・材料
• Research Institution: KITASATO UNIVERSITY
• Principal Investigator: IWAHASHI Makio Kitasato Univ.School of Sci., Professor, 理学部, 教授 (70087120)
• Project Period (FY): 1998 – 2000
• Project Status: Completed (Fiscal Year 2000)
• Budget Amount: ¥3,400,000 (Direct Cost: ¥3,400,000); Fiscal Year 2000: ¥300,000 (Direct Cost: ¥300,000); Fiscal Year 1999: ¥800,000 (Direct Cost: ¥800,000); Fiscal Year 1998: ¥2,300,000 (Direct Cost: ¥2,300,000)
• Keywords: cis-6-octadecenoic acid / cis-9-octadecenoic acid / cis-11-octadecenoic acid / trans-9-octadecenoic acid / fatty acids / self-diffusion coefficient / density / X-ray diffraction for liquid / 脂肪酸 / 自己拡散係数 / 密度 / シス-6-オクタデセン酸 / シス-9-オクタデセン酸 / シス-11-オクタデセン酸 / トランス-9-オクタデセン酸 / オクタデカン酸 / スピン-格子緩和時間 / 液体のX線回析

Research Abstract

The translational movement, the dynamical molecular conformation, and the aggregate structure in the liquid state for three kinds of cis-type unsaturated fatty acids (cis-6-, cis-9-, and cis-11-octadecenoic acids), trans-type unsaturated acid (trans-9-octadecenoic acid), and n-saturated acid (octadecanoic acid) have been studied through the measurements of density, self-diffusion coefficient, ^<13>C NMR spin-lattice relaxation time, and X-ray diffraction. The magnitude of the self-diffusion coefficient, D, fell in sequence of cis-type unsaturated acids > trans-type acids > saturated acid below 350 K.Above 350 K the value of D for the trans-type acid rose to those for the cis-type acids. On the other hand, the density ρ for the acids also fell in the order of cis-type acids > trans-type acid > saturated acid ; the order of the density is just opposite to that expected from the results of the self-diffusion coefficient and other physical properties such as melting point and heat of fusion. This discrepancy between D and ρ values for the acids is well explained by the models of the clusters in their liquids.

Research Products

• [Publications] Makio Iwahashi et al.: "Self-Diffusion,Dynamical Molecular Conformation,and Liquid Structures of n-Saturated and Unsaturated Fatty Acids"Journal of Physical Chemistry B. 104. 6186-6194 (2000)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Makio Iwahashi, Yasutoshi Kasahara, Hideyo Matsuzawa, Kenichiro Yagi, Kenji Nomura, Hikaru Terauchi, Yukihiro Ozaki, and Masao Suzuki: "Self-Diffusion, Dynamical Molecular Conformation, and Liquid Structures of n-Saturated and Unsaturated Fatty Acids"Journal of Physical Chemistry B. 104(26). 6186-6194 (2000)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] M.Iwahashi,Y.Kasahara,H.Matsuzawa,K.Yagi,K.Nomura,H.Terauchi,Y.Ozaki,and M.Suzuki: "Self-Diffusion,Dynamical Molecular Conformation and Liquid Structures of n-Saturated and Unsaturated Fatty Acids"Journal of Physical Chemistry B.. 104(26). 6186-6194 (2000)