The Physics of Lyotropic Liquid Crystals Phase Transitions and Structural Properties

by Figueiredo Neto, Antônio M.; Salinas, Silvio R. A.

• ISBN13: 9780198525509
• ISBN10: 0198525508
• Format: Hardcover
• Copyright: 2005-04-07
• Publisher: Oxford University Press

Summary

This book gives a comprehensive description of the physical properties of lyotropic liquid crystals. Structural features, phase transitions and phase diagrams are discussed in detail. The available experimental data on lyotropic mixtures is presented in the unifying context of the Landau theories. This phenomenological approach is used for establishing connections between structural properties and phase diagrams. The book is suitable for use as a pedagogical introduction to the subject.

Author Biography

Antonio M. Figueiredo Neto is Professor of Physics at Instituto de Fisica, Universidade de Sao Paulo, Brazil. Silvio R. A. Salinas is Professor of Physics at Instituto de Fisica, Universidade de Sao Paulo, Brazil.

Table of Contents

Lyotropic systems: Main experimental facts and techniques	1	(76)
Introduction	1	(17)
The hydrophobic and hydrophilic effects	2	(1)
Amphiphilic molecules	3	(2)
Definition of a lyotropic mixture	5	(1)
Self-assembled systems	6	(2)
Direct and inverted polymorphism	8	(1)
Lyotropic liquid crystalline phases	9	(2)
Structures and terminology	11	(7)
An introductory example	18	(3)
How to prepare a lyotropic mixture (specially for experimentalists)	18	(1)
The potassium laurate (KL) lyotropic mixtures	19	(2)
The lyotropic mesophases	21	(36)
Micellar isotropic phases	22	(1)
Nematic phases	23	(14)
Cholesteric phases	37	(5)
Lamellar phases	42	(6)
Hexagonal and other two-dimensional ordered phases	48	(4)
Three-dimensionally ordered phases	52	(4)
Lower-symmetry phases	56	(1)
Wetting of lyotropic phases	57	(2)
Nematic phase	58	(1)
Sponge phase	59	(1)
Technological and industrial applications	59	(5)
Velocity gradient sensors	62	(2)
Interfaces with biology	64	(13)
References	68	(9)
Basic concepts of phase transitions	77	(35)
Introduction	77	(1)
Critical and tricritical behavior in simple uniaxial ferromagnetic systems	77	(3)
Phase diagrams with bicritical and tetracritical points	80	(3)
Modulated phases and Lifshitz multicritical points	83	(2)
The nematic-isotropic phase transition and the Maier-Saupe model	85	(6)
The Curie--Weiss model	87	(2)
The Maier--Saupe model	89	(2)
The uniaxial--biaxial phase transition	91	(11)
An extension of the Maier--Saupe model	92	(2)
Maier--Saupe model for a mixture of prolate and oblate micelles	94	(4)
Landau theory of the uniaxial-biaxial transition	98	(4)
The smectic A phase transition	102	(2)
Non-critical order parameters and the reconstruction of the phase diagrams	104	(8)
Compressible Ising model	105	(2)
Ferromagnet in a staggered field	107	(2)
Reconstruction of the lyonematic phase diagrams	109	(1)
References	110	(2)
Phase diagrams of lyotropic mixtures	112	(26)
Introduction	112	(1)
General features of phase diagrams	112	(6)
The Gibbs phase rule	115	(1)
Ternary systems	116	(2)
Experimental phase diagrams	118	(11)
Phase diagrams of binary lyotropic mixtures	118	(3)
Phase diagrams of ternary lyotropic mixtures	121	(4)
Phase diagrams of quaternary lyotropic mixtures	125	(2)
Specific features of the topology of phase diagrams of lyotropic mixtures	127	(2)
Calculations for the phase diagrams of binary lyotropic mixtures	129	(9)
Simple example of a binary phase diagram	130	(2)
Additional examples	132	(1)
An illustrative example: Phase diagram of a mixture of sodium laurate and water	133	(3)
References	136	(2)
Phase transitions between periodically organized lyotropic phases	138	(25)
Introduction	138	(1)
The lamellar-tetragonal transition	139	(4)
The effective thermodynamic potential	142	(1)
Phase transitions between direct and reversed mesophases	143	(5)
Fr-non-invariant systems	144	(1)
Fr-invariant systems	145	(2)
Influence of the Fr-symmetry on some experimental phase diagrams	147	(1)
Lyotropic phases with oriented interfaces	148	(3)
Symmetry-breaking undulation mechanism	149	(1)
Field lines and oriented domains	149	(1)
Symmetry of the mesophases with oriented interfaces	150	(1)
The lamellar--hexagonal phase transition	151	(4)
Phenomenological description of the lamellar-hexagonal transition	151	(2)
Tilted hexagonal phases	153	(2)
The lamellar-cubic phase transition	155	(8)
Symmetry basis of the model	155	(1)
Group-theoretical considerations	156	(3)
The bicontinuous cubic phase	159	(2)
References	161	(2)
The isotropic micellar and bicontinuous phases	163	(27)
Introduction	163	(1)
The micellar L1 and L2 isotropic phases: Experimental facts	163	(11)
Self-assembling of amphiphiles in dilute solutions	164	(5)
Self-organization of amphiphiles in semi-dilute and concentrated regimes	169	(5)
The sponge L3 phase	174	(7)
Light scattering experiments: Osmotic compressibility, diffusion, and relaxation times	174	(3)
Small-angle X-ray and neutron scattering experiments	177	(1)
Electrical conductivity and viscosity measurements	178	(2)
Flow-induced birefringence	180	(1)
Calculations for the sponge phase	181	(9)
The lattice model of random surfaces	181	(2)
Landau expansion and phase diagrams	183	(4)
References	187	(3)
The nematic and cholesteric phases	190	(29)
Introduction	190	(1)
The potassium laurate/decanol/water mixture	190	(10)
Identification of the nematic structures by various experimental techniques	190	(1)
The calamitic, discotic, and biaxial phases	191	(5)
Phenomenological calculations for the nematic transitions	196	(4)
Nematic phases in other lyotropic mixtures	200	(5)
Binary mixtures	200	(1)
Multicomponent mixtures	201	(4)
Lyotropic cholesteric mixtures	205	(14)
An introductory example	206	(3)
Phenomenological theory of the cholesteric transitions	209	(6)
Cholesteric phases in other lyotropic mixtures	215	(1)
References	216	(3)
The lyotropic one-, two- and three-dimensionally ordered phases	219	(35)
Lamellar phases	219	(13)
Introduction	219	(1)
An introductory example: sodium dodecylsulfate-based mixtures	220	(2)
The Lα phase in some lyotropic mixtures	222	(4)
Structures of the lamellar phases	226	(6)
Two- and three-dimensionally ordered phases	232	(22)
Introduction	232	(1)
Two-dimensional phases	232	(10)
Three-dimensionally ordered phases	242	(6)
The mesh phase	248	(1)
References	249	(5)
Recent developments and related areas	254	(47)
Introduction	254	(1)
Magnetic colloids	255	(16)
Definition of a ferrofluid	255	(1)
Surfacted ferrofluids	255	(1)
Ionic ferrofluids	256	(2)
Stability of the colloid	258	(2)
The mechanisms of rotation of the magnetic moment	260	(1)
Thermodiffusion in ferrofluids: The Soret effect	261	(3)
Doping of liquid crystals with ferrofluids	264	(7)
Microemulsions	271	(4)
Phase diagrams	272	(1)
Models and theoretical approaches	273	(2)
Langmuir--Blodgett films	275	(6)
Langmuir films	276	(2)
Deposition of Langmuir-Blodgett films	278	(1)
Characterization of the film	279	(1)
Applications of LB films in the study of lyotropics	280	(1)
Diblock copolymers	281	(5)
Structures of diblock copolymers	282	(4)
New lyotropic-type mixtures	286	(15)
Chromonics	286	(3)
The lyo-banana mesophases	289	(2)
Transparent nematic phase	291	(1)
References	292	(9)
Index	301