Synthesis of inorganic gels in a lyotropic liquid crystal medium. I. Synthesis of silica gels in lamellar phases obtained from non-ionic surfactants

1995 ◽  
Vol 4 (2) ◽  
pp. 107-116 ◽  
Author(s):  
T. Dabadie ◽  
A. Ayral ◽  
C. Guizard ◽  
L. Cot ◽  
C. Lurin ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Lyotropic Liquid Crystal ◽  
Silica Gels ◽  
Ionic Surfactants ◽  
Lamellar Phases ◽  
Crystal Medium

scholarly journals Two-Step Self-Assembly and Lyotropic Liquid Crystal Behavior of TiO2Nanorods

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Zhimin Ren ◽  
Chao Chen ◽  
Rong Hu ◽  
Kaiguang Mai ◽  
Guodong Qian ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Self Assembly ◽  
Driving Force ◽  
Growth Process ◽  
Lyotropic Liquid Crystal ◽  
Synthesis Process ◽  
Lamellar Phases ◽  
Promising Application ◽  
Lower Temperature ◽  
Secondary Assembly

Several self-assembly structures of anatase TiO2nanorods were obtained by a two-step assembly process, and these structures formed different lyotropic liquid crystal in solution. Primary self-assembly occurred in synthesis process and formed two structures, in the morphology of ribbon and honeycomb, respectively. Secondary-assembly took place when the products were placed at lower temperature, where unique structures were obtained as the relative amount of ribbon and honeycomb changed with the increase of TiO2concentration. These structures showed nematic, spherulites, and lamellar phases. The mechanism of the two-step self-assembly was clarified. The driving force of primary assembly is deduced to be anisotropic attractive force, for NRs can assemble at any concentrations, while gravity is the driving force of the secondary assembly. It is worth mentioning that this paper is the first report about spherulites composing of anatase TiO2nanorods. The spherulites obtained were negative or of tangential type, and its structure, growth process, and temperature influences were also investigated. The spherulites may have promising application in temperature microsensor.

Liquid Crystal Templating Effects on Silica Gels Synthesized using Quaternary Ammonium Surfactants

1994 ◽  
Vol 346 ◽  
Author(s):  
T. Dabadie ◽  
A. Ayral ◽  
C. Guizard ◽  
L. Cot ◽  
J.C. Robert ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Quaternary Ammonium ◽  
Sol Gel ◽  
Structural Evolution ◽  
Lyotropic Liquid Crystal ◽  
Silica Gels ◽  
Promising Tool ◽  
Crystal Phases ◽  
Quaternary Ammonium Surfactants ◽  
Liquid Crystal Phases

ABSTRACTThe use of lyotropic liquid crystal phases is a promising tool in tailoring the porous structure of inorganic gels. In this work, we examine the effect of hexagonal liquid crystal phases produced with quaternary ammonium surfactants on the textural ordering of silica gels.The sol-gel polymerization of the silicon alkoxide precursor (tetramethoxysilane) is followed by 29Si NMR and rheological measurements. The structural evolution of the material from the starting sol to the thermally treated gel is studied using low angle X-ray diffraction. The textural characteristics of the gels are correlated with the nature of the surfactant molecules.

scholarly journals Hydrogen-bonded silica gels dispersed in a smectic liquid crystal: A random fieldXYsystem

2002 ◽  
Vol 65 (5) ◽  
Author(s):  
S. Park ◽  
R. L. Leheny ◽  
R. J. Birgeneau ◽  
J.-L. Gallani ◽  
C. W. Garland ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Silica Gels ◽  
Smectic Liquid Crystal ◽  
Hydrogen Bonded

Lamellar Lyotropic Liquid Crystal Phases as a Carrier for Skin Delivery of Morus alba Stem Extract

2021 ◽  
Vol 901 ◽  
pp. 67-72
Author(s):  
Chein Yhirayha ◽  
Sakchai Wittaya-Areekul ◽  
Tasana Pitaksuteepong
Keyword(s):  
Liquid Crystal ◽  
Biological Activities ◽  
Polarized Light ◽  
Water Extract ◽  
Skin Penetration ◽  
Morus Alba ◽  
Lyotropic Liquid Crystal ◽  
Mixed Surfactant ◽  
Skin Delivery ◽  
Stem Extract

Morus alba stem extract possesses several biological activities. However, skin delivery of the extract is limited by the stratum corneum. In this study, lamellar lyotropic liquid crystal (LLC) was investigated for the potential application in the skin delivery of M. alba stem extract. The four formulations were developed and incorporated with M. alba stem extract at 3% w/w. These formulations were stored at room temperature in light-protected containers for 3 months. The optical pattern under polarized light microscope, viscosity and remaining of the extract were determined. The skin penetration enhancing property of the formulations was investigated using excised porcine ear skin model. The results showed that all formulations remained stable after 3-month storage. The two formulations exhibiting good penetration enhancing properties were F3 consisting of PEG-7 glyceryl cocoate/n-Dodecane/Water/extract (55.29/19.40/22.31/3.00 %w/w) and F4 consisting of mixed Surfactant/n-Dodecane/Water/extract (48.50/4.85/43.65/3.00 %w/w). The mixed surfactant composed of PEG-7 glyceryl cocoate/PEG-40 hydrogenated castor oil/Glyceryl oleate (40/33.24/26.76 %w/w). It can be concluded that the lamellar LLC formulations developed in this study can be used as a carrier for delivering of M. alba stem extract. The components of the formulations which play important roles are the oil and the surfactant.

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