Lamellar functional materials

SYNTHESIS OF LAMELLAR FUNCTIONAL MATERIALS BY SELF-ASSEMBLY... 

We then showed that this strategy could be extended to the formation of lamellar functional materials starting from bridged organosilica precursors with long alkylene... 

Scheme 12.16. Preparation of amino functionalized lamellar hybrid materials by self-assembly.

Fig. 18. Plot of residual depth parameter as a function of the ratio H/E according to equation 10. A value of v = 0.41 is taken for PE. Data for die-drawn PE (O) and POM ( ) and for soda-glass (A) and hard-steel (A) are shown. H/E values for lamellar isotropic PE with a 200 A thick surface (ft) and isotropic chain-extended material (1 2 x 103 A) (f) are also indicated...

The fact that crystalline polymers are multiphase materials has prompted a new approach in characterizing their internal structure (lamellar thickness, perfection, etc.) and relating it to the hardness concept (volume of material locally deformed under a point indenter). In lamellar PE microhardness is grossly a given increasing function of lamellar thickness. In using the composite concept care must be exercised to emphasize and properly account for the non-crystalline phase and its various... 

If the scattering entities in our material are stacks of layers with infinite lateral extension, Eq. (8.47) is applicable. This means that we can continue to investigate isotropic materials, and nevertheless unwrap the ID intensity of the layer stack. To this function Ruland applies the edge-enhancement principle of Merino and Tchoubar (cf. Sect. 8.5.3) and receives the interface distribution function (IDF), gi (x). Ruland discusses isotropic [66] and anisotropic [67] lamellar topologies. 

Layered materials are of special interest for bio-immobilization due to the accessibility of large internal and external surface areas, potential to confine biomolecules within regularly organized interlayer spaces, and processing of colloidal dispersions for the fabrication of protein-clay films for electrochemical catalysis [83-90], These studies indicate that layered materials can serve as efficient support matrices to maintain the native structure and function of the immobilized biomolecules. Current trends in the synthesis of functional biopolymer nano composites based on layered materials (specifically layered double hydroxides) have been discussed in excellent reviews by Ruiz-Hitzky [5] and Duan [6] herein we focus specifically on the fabrication of bio-inorganic lamellar nanocomposites based on the exfoliation and ordered restacking of aminopropyl-functionalized magnesium phyllosilicate (AMP) in the presence of various biomolecules [91]. 

Patil, A.J., Muthusamy, E. and Mann, S. (2005) Fabrication of functional protein-organoclay lamellar nanocomposites by biomolecule-induced assembly of exfoliated aminopropyl-functionalized magnesium phyllosilicates. Journal of Materials Chemistry, 15, 3838-3843. 

PCH materials offer new opportunities for the rational design of heterogeneous catalyst systems, because the pore size distributions are in the supermicropore to small mesopore range (14-25A) and chemical functionality (e.g., acidity) can be introduced by adjusting the composition of the layered silicate host. The approach to designing PCH materials is based on the use of intercalated quaternary ammonium cations and neutral amines as co-surfactants to direct the interlamellar hydrolysis and condensation polymerization of neutral inorganic precursor (for example, tetraethylorthosilicate, TEOS) within the galleries of an ionic lamellar solid. 

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