Nonlinear shear response and anomalous pressure dependence of viscosity in a Langmuir monolayer

被引:33
作者
Ghaskadvi, RS [1 ]
Ketterson, JB [1 ]
Dutta, P [1 ]
机构
[1] NORTHWESTERN UNIV,DEPT PHYS & ASTRON,EVANSTON,IL 60208
关键词
D O I
10.1021/la970036d
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
We have studied the strain response of heneicosanoic acid monolayers to an applied sinusoidal shear stress. We have measured the complex shear modulus (G = G' + iG'') as a function of strain amplitude and frequency, monolayer pressure, and temperature. We find that G' and G'' are independent; of the strain only at very small strain amplitudes; beyond an 'elastic limit', both G' and G'' decrease with increasing strain amplitude. G' and G'' are discontinuous at the L-2-L-2' and L-2'-S phase transitions. In the low-pressure L-2 phase, G' and G'' first increase with increasing pressure and then anomalously decrease. Compared to existing X-ray data, we find an unexpected correlation: over a range of temperatures, the pressure at which G'' is a maximum is also the one at which the monolayer lattice is hexagonal (undistorted).
引用
收藏
页码:5137 / 5140
页数:4
相关论文
共 17 条
  • [1] CENTRO-SYMMETRIC TECHNIQUE FOR MEASURING SHEAR MODULUS, VISCOSITY, AND SURFACE-TENSION OF SPREAD MONOLAYERS
    ABRAHAM, BM
    MIYANO, K
    XU, SQ
    KETTERSON, JB
    [J]. REVIEW OF SCIENTIFIC INSTRUMENTS, 1983, 54 (02) : 213 - 219
  • [2] ANOMALOUS MELTING PROPERTIES OF SOME CLASSICAL MONOLAYER SYSTEMS
    ABRAHAM, BM
    MIYANO, K
    KETTERSON, JB
    XU, SQ
    [J]. PHYSICAL REVIEW LETTERS, 1983, 51 (21) : 1975 - 1978
  • [3] APPARATUS WITH AN ELASTIC BARRIER FOR RADIAL COMPRESSION OF LIQUID SUPPORTED MONOLAYERS
    BOHANON, TM
    MIKRUT, JM
    ABRAHAM, BM
    KETTERSON, JB
    JACOBSON, S
    FLOSENZIER, LS
    TORKELSON, JM
    DUTTA, P
    [J]. REVIEW OF SCIENTIFIC INSTRUMENTS, 1992, 63 (02) : 1822 - 1825
  • [4] SURFACE-TENSION ANISOTROPY AND RELAXATION IN UNIAXIALLY COMPRESSED LANGMUIR MONOLAYERS
    BOHANON, TM
    LEE, AM
    KETTERSON, JB
    DUTTA, P
    [J]. LANGMUIR, 1992, 8 (10) : 2497 - 2500
  • [5] BOHANONTM, 1992, REV SCI INSTRUM, V62, P2959
  • [6] A superliquid in two dimensions and a first-order change in a condensed monolayer II Abnormal viscosity relations of alcohol monolayers in condensed liquid phases
    Copeland, LE
    Harkins, WD
    Boyd, GE
    [J]. JOURNAL OF CHEMICAL PHYSICS, 1942, 10 (06) : 357 - 365
  • [7] X-RAY-DIFFRACTION STUDY OF A RECENTLY IDENTIFIED PHASE-TRANSITION IN FATTY-ACID LANGMUIR MONOLAYERS
    DURBIN, MK
    MALIK, A
    GHASKADVI, R
    SHIH, MC
    ZSCHACK, P
    DUTTA, P
    [J]. JOURNAL OF PHYSICAL CHEMISTRY, 1994, 98 (07) : 1753 - 1755
  • [8] Viscosity, plasticity, and diffusion as examples of absolute reaction rates
    Eyring, H
    [J]. JOURNAL OF CHEMICAL PHYSICS, 1936, 4 (04) : 283 - 291
  • [9] Ferry D.J., 1980, Viscoelastic Properties of Polymers, V3e
  • [10] Direct visualization of flow-induced anisotropy in a fatty acid monolayer
    Friedenberg, MC
    Fuller, GG
    Frank, CW
    Robertson, CR
    [J]. LANGMUIR, 1996, 12 (06) : 1594 - 1599