Exfoliation definition

Fibers are observed by STM as thin tubes about 2.5 nm in diameter and 20 nm long formed by agglomeration of threads. Atomic resolution at fibers can also be obtained, although with a poor definition. They are produced by step rupture by exfoliation. 

Synonyms Hydrated magnesium aluminum iron silicate Definition Hydrated magnesium-iron-aluminum silicate a specific form of mica that exfoliates under heat into thin, lightweight flakes Properties Lt. brown platelet-type cryst. structure sol. in hot cone, sulfuric acid insol. in water and org. soivs. sp.gr. 2.25 bulking value 0.053 gal/lb... 

Definition Extract obtained from honey Uses Biological additive, moisturizer in cosmetics exfoliating agent, conditioner for skin care preps. 

Uses Humectant in cosmetics Hydrogenated isomaltulose. See Isomalt Hydrogenated jojoba oil CAS 92457-12-0 EINECS/ELINCS 296-292-4 Synonyms Jojoba oil, hydrogenated Definition End prod, of the controlled hydrogenation of jojoba oil Uses Abrasive, emollient, skin conditioner, exfoliant in cosmetics Features Oily... 

Jojoba (Buxus chinensis) powder Synonyms Buxus chinensis Jojoba powder Jojoba seed powder Powdered jojoba seed Definition Powder obtained from the ground seeds of jojoba, Buxus chinensis Uses Exfoliant for cosmetics Trade Name Synonyms Jojoba Meal 24/60 [Floratech Am. http //www.floratech.com]. Jojoba Meal 40 [Floratech Am. http //www.floratech.com]. Jojoba Meal 60 [Floratech Am. http //www.floratech.com] Jojoba esters... 

Synonyms Esterase, jojoba wax Definition Semisolid fraction of jojoba oil Uses Emollient in cosmetics natural chewing gum base exfoliant for cosmetics Regulatory Japan approved Trade Name Synonyms Jojoba 28/60 Gypsy Rose [Floratech Am. 

In general, the dispersion of clay particles in a polymer matrix can result in the formation of three general types of composite materials (Figure 1). Conventional composites contain clay tactoids with the layers aggregated in unintercalated face - face form. The clay tactoids are simply dispersed as a segregated phase. Intercalated clay composites are intercalation compounds of definite structure formed by the insertion of one or more molecular layers of polymer into the clay host galleries and the properties usually resemble those of the ceramic host. In contrast, exfoliated polymer-clay nanocomposites have a low clay content, a monolithic structure, a separation between layers that depends on the polymer content of the composite, and properties that reflect those of the nano-confmed polymer. 

WAXS indicated that higher levels of vinyl acetate and PEMA could provide more efficient dispersion of the montmorillonite. Since no TEM pictures were provided, the degree of exfoliation of the montmorillonite in the polymer blends cannot be assessed definitively. No experimental design was provided and no statistical analysis was carried out. No analysis was provided to determine the statistical relevance of the presumed significant independent variables, vinyl acetate and PEMA content. 

Full exfoliation of montmorillonite in polystyrene has not been achieved. Hence, the full realization of the reinforcing benefit of montmorillonite with regard to the mechanical property enhancement of polystyrene has not been exploited. The definitive discussion that relates to the complex and confounding problem relating to the inability to exfoliate montmorillonite into polystyrene is found in the work of Stretz and Paul [31]. The factors that relate to improved dispersion and exfoliation of montmorillonite in polyolefins that are discussed above do not provide a satisfying response with polystyrene. The conclusion found in this work is the result of extensive investigations of acrylonitrile (SAN) and maleic anhydride (SMA) modified polystyrene [32,33,34]. 

Eurther work needs to be done with WAXS, a higher magnification TEM, and tensile modulus evaluations of injected molded test samples before a definite judgment can be made concerning the degree of exfoliation of this organomontmorillonite in a styrene composite prepared by bulk polymerization. 

However, it is difficult to draw definitive conclusions on the microstructure of the nanocomposites from XRD patterns exhibiting diffraction patterns, as the relatively featureless diffraction pattern of the exfoliated structure may have been covered up by the diffraction peak of the intercalated structure. In some cases, the featureless diffraction patterns do not mean exfoliated structure. Therefore TEM is necessary to determine the nature of the nanocomposites and to provide additional information that will be helpful in the interpretation of the XRD results. 

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