Composites exfoliation

Micro-composites are formed when the polymer chain is unable to intercalate into the silicate layer and therefore phase separated polymer/clay composites are formed. Their properties remain the same as the conventional micro-composites as shown in Figure 2(a). Intercalated nano-composite is obtained when the polymer chain is inserted between clay layers such that the interlayer spacing is expanded, but the layers still bear a well-defined spatial relationship to each other as shown in Figure 2(b). Exfoliated nano-composites are formed when the layers of the day have been completely separated and the individual layers are distributed throughout the organic matrix as shown in Figure 2(c). 

Thermally exfoliated graphite (TEG) and their composites from Superior Graphite (Chicago) and TEGs prepared from Ukrainian graphite. 

Carbon composites Anatase TiCL Nanoscrolls Exfoliated graphite. 

Exfoliated graphite - amorphous carbon (EG-AC) composites are widely used in a broad range of applications like adsorption of gases and liquids, separation, and high-surface catalyst supports. They also seem to be attractive for energy- and gas- storage systems. 

In our laboratory we have elaborated the method of producing residual graphite hydrosulfate, which could be exfoliated efficiently at temperatures of about 500°C3. Having such GIC we tried to realize one-stage procedure of producing EG-AC composites. 

Modestov A., Glezer V., Maryasin I., Lev O. Photocatalytic degradation of chlorinated phenoxyacetic acids by a new buoyant titania - exfoliated graphite composite photocatalyst. J Phys Chem B 1997 101 4623-9. 

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]. 

U. Khan, P. May, A. O Neill, J.N. Coleman, Development of stiff, strong, yet tough composites by the addition of solvent exfoliated graphene to polyurethane, Carbon, 48 (2010) 4035-4041. 

This technique involves the dispersion of a nanomaterial in a monomer (Fig. 4.8). This step requires a certain amount of time that depends on the polarity of the monomer molecules, the surface treatment of the nanomaterial, and the swelling temperature. For thermoplastics, the polymerization can be initiated either by the addition of an agent or by an increase in temperature. For thermosets such as epoxies or unsaturated polyesters, a curing agent or peroxide can be added in order to initiate the polymerization. Functionalized nanomaterials can improve their initial dispersion in the monomer and consequently in the composites. In the case of layered materials, such as clays or graphene, the most important step is the penetration of the monomer between the sheets, thus allowing the polymer chains to exfoliate the material. The... 

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