Organo-montmorillonite

XRD was used to investigate the spacings of silicate layers of montmorillonite (from 1.9 to 4nm) in PP/montmorillonite (MMT) nanocomposites prepared by in situ graft-intercalation in the presence of acrylamide [331]. Similarly, XRD and TEM were used to study the dispersibility of PP/MMT nanocomposites prepared by melt intercalation using organo-montmorillonite and conventional twin screw extrusion [332]. Various delaminated and intercalated polymer (PA6, PA 12, PS,... 

PP-g-MA) silicate nanocomposites and intercalated thermoset silicate nanocomposites for flame-retardant applications were characterised by XRD and TEM [333], XRD, TEM and FTIR were also used in the study of ID CdS nanoparticle-poly(vinyl acetate) nanorod composites prepared by hydrothermal polymerisation and simultaneous sulfidation [334], The CdS nanoparticles were well dispersed in the polymer nanorods. The intercalation of polyaniline (PANI)-DDBSA (dodecylbenzene-sulfonate) into the galleries of organo-montmorillonite (MMT) was confirmed by XRD, and significantly large 4-spacing expansions (13.3-29.6A) were observed for the nanocomposites [335],... 

Several conditions are necessary for satisfactory surface coatings, e.g., nondrip applications. There is a balance between the ease of use and sagging of the paint during and after administration. Thixotropic additives, e.g., organo-montmorillonite clays are added. These form 3-dimensional networks, which are easily broken down by shear. 

Figure 7. Enthalpy of wetting at different mass of the organo-montmorillonite in methanol. 1. TDP-, 2. HDP-, 3. DMDH-montm. 4. Benton 34.

Figure 8. The molar immersional wetting enthalpy on organo-montmorillonite with different hydrophobicity in methanol (----nonswelling illite,--swelling montmorillonite).

Li, W., Huang, Y. D., and Ahmadi, S. J., Preparation and properties of ethylene-propylene-diene rubber/organo-montmorillonite nanocomposites, J. Appl. Polym. ScL, 94, 440-445 (2004). 

Chow, W.S., Lok, S.K. Flexural, morphological and thermal properties of polylactic acid/ organo-montmorillonite nanocomposites. Polym. Polym. Compos. 16(4), 263-270 (2008)... 

Biobased epoxy nanocomposites can be reinforced with organo montmorillonite clay and carbon fibers obtained from poly(acryl-onitrile) (45). To get the organically modified clay into the glassy biobased epoxy networks, a sonication technique was used. In this way, clay nanoplatelets were obtained that were homogeneously dispersed and completely exfoliated in the matrix. 

Chang, Y. W., Yang, Y, Ryu, S., and Nah, C. Preparation and properties of EEPDM/organo-montmorillonite hybrid nanocomposites. Polymer International 51 319. 

In this chapter we have divided modified clays in two different types namely organomodified montmorillonite (OMt) and expanded organo-montmorillonite (EOMt). The effect of these clay particles in NR matrix will be discussed elaborately in the forthcoming section. 

Preparation and characterization of EOMt was first reported by Das et al. Pre-intercalation of OMt was done by stearic acid. Stearic acid and OMt were taken in a porcelain mortar at a ratio of 1 1 by mass and well mixed by a pestle. The mixture was kept in an oven at 110 °C for 15 min. The mass was then cooled to room temperature and ground up again. This step was done several times to obtain a homogeneous mass. The resulting product was called expanded organo-montmorillonite (EOMt). 

Natural Rubber-Organo-Montmorillonite Nanocomposites in the Presence of External Compatibilizers... 

Natural Rubber-Expanded Organo-Montmorillonite Nanocomposites... 

Natural rubber/cw-1,4-polybutadiene (NR/BR) blends (70/30 mass ratio) have been widely used in the tire industry. Many nanocomposites based on organo-montmorillonite (OMMT)/rubber blends have been investigated. However, relatively little attention had been paid to binary rubber hybrids/ montmorillonite nanocomposites, and according to Zheng Gu et ah, no studies existed dealing with OMMT/NR/BR nanocomposites. So, the authors described the preparation of OMMT/NR/BR nanocomposites by direct mechanical blending and determined the cure characteristics, static mechanical properties, dynamic mechanical properties, and thermal stability of the nanocomposites. OMMT/NR/BR nanocomposites had exactly the same onset decomposition temperature and lower thermal degradation rate as the NR/BR blends. 

C. W. Shyang, Tensile and thermal properties on poly(butylene terephthal-ate)/organo-montmorillonite nanocomposites, Malaysian Polymer Journal rMP/), 3 1-13,2008. 

Arroyo M, Manchado MAL, Herrero B (2003) Organo-montmorillonite as substitute of caibon black in natural mbber compounds. Polymer 44 2447-2453... 

R. Scaffaro, M. C. Mistretta, F. P. La Mantia, and A. Frache, Effect of heating of organo-montmorillonites under different atmospheres. Applied Clay Science, 45 (2009), 185-93. 

Nanocomposite conventional mesoscale fibers (textile fibers that carry nanoparticulate filler) are produced via conventional fiber-spinning techniques by incorporating well-dispersed nanoparticles into the spinning dope. For instance, an intercalated poly(ethylene terephthalate) (PET)/organo-montmorillonite (MMT) nanocomposite prepared by in situ polymerization of the polyester in the presence of MMT clay was successfully melt spun into microfibers (Guan, G.-H., et al. 2005). Melt-spun conventional fibers of... 

Chiu F-C, Fu S-W, Chuang W-T and Sheu H-S (2008) Fabrication and characterization of polyamide 6,6/organo-montmorillonite nanocoinposites with and without a maleated polyolefin elastomer as toughener, Po/ywer 49 1015-1026. 

Gatos, K.G., Szazdi, L., Pukdnszky, B., and Karger-Kocsis, J. (2005) Controlling the deintercalation in hydrogenated nitrile rubber (HNBR)/organo-montmorillonite nanocomposites by curing with peroxide. Macromolecular Rapid Communications,... 

The choice of Cloisite 30B has been demonstrated in the work above as an excellent choice for exfoliation into nylon 6. The choice of Cloisite 15A is not good, based on the work above. One must be cautious when comparing the results with Cloisite 15A and Cloisite 20A. Both organo-montmorillonites utilize the same quat treatment. However, Cloisite 15A has an excess of approximately 30 meq/lOOg of montmorillonite of quat past the exchange capacity of the montmorillonite. This excess quat could diffuse into the polymer and alter the mechanical properties of the composite. The counterion of this excess quat will be chloride. The montmorillonite content in the polymer was 3.7 wt.% for Cloisite 30B and 3.1 wt.% for Cloisite 15A. 

A more pertinent evaluation of the roll of processing conditions to exfohation of montmorillonite in nylon 6 to the discussions above is provided by Chavarria et al. [7]. The nylon 6 that was evaluated was the higher molecular weight version that was evaluated above. The organo-montmorillonite was prepared by exchanging trimethyl hydrogenated... 

The Young s modulus was the highest for the polymer nanocomposites prepared with the Werner and Pfleiderer extruders when the organo-montmorillonite was added downstream to the molten polymer. The lowest Young s modulus value was obtained when the polymer was added together with the organomontmorillonite. The Haake extruder produced polymer composites with the second highest modulus values, followed by the samples prepared with the DSM extruder. 

Epoxies have been toughened with elastomer-dispersed phases with a decrease in modulus. Work by Balakrishnan et al. [35] utilized organo-montmorillonite as a dispersed phase in elastomer-toughened epoxies to recover this lost modulus. The montmorillonite was modified with octadecyl ammonium ion. The elastomer-dispersed phase in the epoxy was prepared by free radical polymerization of acrylic monomer within the epoxy. The acrylic elastomer-dispersed phase had epoxy functionality provided through the utilization of glycidyl methacrylate as a comonomer. 

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