SANS studies of liquid crystalline microemulsion gels

Sans Studies of Liquid Crystalline Microemulsion Gels

We have investigated by small-angle neutron scattering (SANS) the ternary system containing water, alkane and the surfactant mixture benzyltetradecyldimethylammonium chloride and tetradecyltrimethylammonium bromide, which we have found to form a cubic liquid crystalline phase. A contrast variation experiment with equal volume fractions of water and oil showed three Bragg reflections varying in ...

Isotropic-cholesteric transition in liquid-crystalline gels.

In a nematic gel, the appearance of nematic order is accompanied by a spontaneous elongation of the gel parallel to the nematic director. If such a gel is made chiral, it has a tendency to form a cholesteric helical texture, in which local elongation of the gel parallel to the nematic director is suppressed due to the requirement of elastic compatibility. We show that a conical helix in which t...

Buckling instability in liquid crystalline physical gels.

In a nematic gel we observe a low-energy buckling deformation arising from soft and semisoft elastic modes. We prepare the self-assembled gel by dissolving a coil-side-group liquid-crystalline polymer-coil copolymer in a nematic liquid crystal. The gel has long network strands and a precisely tailored structure, making it ideal for studying nematic rubber elasticity. Under polarized optical mic...

Physical gels made of liquid crystalline B4 phase.

The achiral liquid crystalline materials showing two B4 (HN) phases have been found to exhibit strong gelation ability for various organic solvents with reversible sol-gel phase transition. The gel is formed by helical tubules, which build entangled 3D network, encapsulating the solvent. The equilibrium of left- and right-handed tubules is preserved in the gel, even if the chiral solvent is used.

Liquid Crystalline Gels by Self-Assembly of Triblock Copolymers