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Hierarchical Structureand Dynamics of
Softmatters
Hideki SetoNeutron Scattering Laboratory, IMSS, KEK
Softmatter (=Soft Condensed Matter)
Polymers Liquid Crystals
ColloidsAmphiphilic molecules
Amphiphilic Polymer
Emulsion
Polymer Liquid Crystal
Liquid Crystal ColloidLyotropic Liquid Crystal
Liquid Crystal Polymer
directional order
water oil
hydrophobichydrophilic
Polymers Liquid Crystals
ColloidsAmphiphilic molecules
Applications of Softmatters
engineering plastic
film
thermography
display
detergent
soappaint
cosmetics
Softmatters in LivesPolymers Liquid Crystals
ColloidsAmphiphilic molecules
phospholipid
glycolipid
bio-membrane
blood
protein
DNA
cell
bio-membrane
10-9 10-6 10-3 m
membrane protein
peptide
Hierarchical Structureof Biological System
lipid membranephospholipid
10-9 10-6 10-3 m
transparent liquidmicroemulsiono/w dropletamphiphilicmolecules
Hierarchical Structureof Softmatters
Hierarchical Structure andDynamics
d(Å)
103
100
10-3
10-6
10-9
10-12
100 101 102 103
Two-level motion
Local motion
(!-process)
Segmental motion
("-process)
CooperativeD iffusion
Reptation
104
Methods to investigateSoftmatters
Small-Angle X-ray Scattering Small-Angle Neutron Scattering Neutron Spin Echo
X-ray Reflectometer/GI-SAXS Neutron Reflectometer Neutron Total Scattering
10<d<1000Å, time slice(Δt>10ms) 20<d<3000Å, contrast variation 5<d<1000Å, quasi-elastic(ΔE~10neV)
10<d<1000Å, surface structure 10<d<700Å, air/liquid interface 0.06<d<800Å, wide Q-range
PF
ISSP/JAEAISSP/JAEA
J-PARC
J-PARC
SPring-8
Structures of microemulsions
Surfactant
Water Oil
Lamellar
Spherical MicellesInverted Micelles
Irregular Bicontinuous
Hexagonal
Inverted CubicCubic
Cylindrical Micelles
Bending energy
R1
R2
mean curvature H =1
2
1
R1+1
R2
!
"#
$
%&
Gaussian curvature K =1
R1
1
R2
Ebend = '(H (1
Rs)2+'K
)
*+
,
-./ dS
spontaneous curvature
saddle-splay modulusbending modulus
W. Helfrich, Z. Naturforsch. C28 (1973) 693
AOT+D2O+decane
Effects of T and P seem to be the same
Temperature induced phase transition
Pressure?
BL-15A, Photon Factory, KEK
P-dependence of SAXS
droplet
lamellar
T- and P-dependences of inter-dropletpotential
Pressure-induced phase transition
P- and T- dependence of membranefluctuation were investigated by NSE
Kawabata, Seto et al., PRL 2004, JCP 2007
iNSE at JRR-3M, JAEA (ISSP)
P- and T-variations of I(Q,t)
T
P
ambient temperature/pressure
I(Q,t)/I(Q,0)=exp(-DeffQ2t)
Bending modulus
Effects of Pressure and Temperature
Temperature
Pressure
Rs(spontaneous curvature)
κ(bending modulus)
decrease
decrease increase
decrease
Future works to be investigated at CMRC?
for example: “raft” structure of bio-membrane
How the “raft”structure is organized?
How the membraneproteins work?
Hybridization of softmatters
SANS/SAXS/NSE XR/NR/GI-SAS
polymer supported model bio-membrane
Tanaka & Sackmann, Nature 2005
phase separation of a mixture of lipids
Vietch & Keller, PRL 2002
Yamada et al., submitted
How the “raft”structure is organized?
How the membraneproteins work?