Clay surfaces, modified

Pantoustier, N., Alexandre, M., Degee, P, Calberg, C., Jerome, R., Henrist, C., et al. (2001). Poly(3-caprolactone) layered silicate nanocomposites effect of clay surface modifiers on the melt intercalation process. e-Polymer, 9, 1-9. 

Sondi, I.. Milat, O., and Pravdic, V., Electrokinetic potentials of clay surfaces modified by polymers, J. Colloid Interf. Sci., 189, 66, 1997. 

Ha Ha, S.-R., Rhee, K.-Y., Kim, H.-C., Kim, J.-T. Fracture performance of clay/epoxy nanocomposites with clay surface-modified using 3-aminopropyltriethoxysilane. CoUoids and Surfaces A - Physicochemical and Eng. Aspects 313-314 (2008) 112-115. 

Due to their rigid nature, clay platelets can function as nucleating agents that are able to modify the ciystallization behavior of the polymer matrix such as PVDF-HFP. Organically modified clay promotes an a- to 3-transformation of the polymer crystals. The degree of transformation depends on the nature of the clay surface modifier and the strength of the interactions between the clay and the polymer. ... 

Koo and co-workers [149] compared the benefits of incorporating three different types of nanoparticles on the mechanical properties of PA. The nanoparticles used were montmorillonite clay, surface modified silica and carbon nanofibre. 

Triantafillidis, C.S. LeBaron, P.C. Pinnavaia, T.J. Thermoset epoxy-clay nanocomposites the dual role of alpha.omega-diamines as clay surface modifiers and pol3mer curing agents. J. Solid State Chem. 2002, 167, 354-362. 

Ha S R, Rhee K Y, Kim H C and Kim J T (2008) Fracture performance of clay/epoxy uanocomposites with clay surface-modified using 3-aminopropyltriethoxysilane, Coll Surf A Physicochem Eng Aspects 313-314 112-115. 

Nanoadditives can increase the crystallinity behavior of a material and the transformation to polymer crystal. This effect was observed in poly(vinylidene fluoride-co-hexafluoropropylene), PVDF—EVA, enhanced by organically modified clay (Kelarakis et al., 2010). The transformation from the a-phase type to the P-phase of the crystalline stmcture depends on the nature of the clay surface modifier and scales as well as the strength of the interactions between the clay and polymer... 

E - clay surface modified with 25-30 wt% octadecylamine (Nanoclay, USA),... 

P - clay surface modified with 35 - 45 wt% dimethyl dialkyl (C14-C18) amine... 

In the case of LASIP with clay nanoparticles, polystyrene was grafted using a DPE coinitiator. The montmorillonite clay surface and intergallery interfaces were intercalated with 1,1-diphenylethylene (DPE) modified to be an organic cation as shown in Fig. 4. Its intercalation was confirmed by a series of characterization methods including X-ray diffraction (XRD), FT-IR spectroscopy, TGA, and XPS. The results showed a complete replacement of... 

These examples illustrate that biomolecules may act as catalysts in soils to alter the structure of organic contaminants. The exact nature of the reaction may be modified by interaction of the biocatalyst with soil colloids. It is also possible that the catalytic reaction requires a specific mineral-biomolecule combination. Mortland (1984) demonstrated that py ridoxal-5 -phosphate (PLP) catalyzes glutamic acid deamination at 20 °C in the presence of copper-substituted smectite. The proposed pathway for deamination involved formation ofa Schiff base between PLP and glutamic acid, followed by complexation with Cu2+ on the clay surface. Substituted Cu2+ stabilized the Schiff base by chelation of the carboxylate, imine nitrogen, and the phenolic oxygen. In this case, catalysis required combination of the biomolecule with a specific metal-substituted clay. 

The clay surface increases the probability of reagents meeting and modifies the reagents polarity. 

Special surface modifications are available to further improve reinforcement. The objective of the surface treatment is to increase filler loading and/or improve physical properties without loss of rheological characteristics. A variety of surface-modified kaolins have been introduced including clays treated with silane, titanate, polyester, and metal hydroxide. Silane-treated kaolin is used in applications requiring maximum aging characteristics in the service environment. 

LogKof Different Groups at Clay Surfaces According to Modified MUSIC Model... 

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