Clays foaming process

Nam PH, Maiti P, Okamoto M, Kotaka T, Nakayama T, Takada M, Ohshima M, Usuki A, Hasegawa N, Okamoto H (2002) Foam processing and cellular structure of polypropy-lene/clay nanocomposites. Polym Eng Sci 42 1907-1918... 

Nam, R H., Maiti, R, Okamoto, M., Kotaka, T., Nakayama, T., Takada, M., Ohshima, M., Usuki, A., Hasegawa, N., and Okamoto, H., Foam processing and cellular structure of polypropylene/clay nanocomposites, Polym. Eng. ScL, 42, 1907-1918 (2002). Navarro-Banon, V., Vega-Baudrit, J., Vaquez, R, and Martm-Martinez, J. M., Interactions in naosilica-polyurethane composites evidenced by plate-plate rheology and DMTA, Macro-mol. Symp., 221, 1-10 (2005). 

Mitsunaga, M., Ito, Y., Ray, S. S., Okamoto, M., and Hironako, K. 2003. Intercalated polycarbonate/clay nanocomposites Nanostructure control and foam processing. Macromol Mater Eng 288 543. 

Poly(methyl methacrylate) (PMMA) was also used in MMT nanocomposite foam preparation (Fu and Naguib, 2006 Weickmann et al, 2010). Organomodified MMT was used in its preparation by in situ bulk polymerization and batch foaming process with N2. The MMT acted as a heterogeneous nucleation agent in polymer matrix that reduced cell size and increased cell density. Moreover, MMT addition decreased dielectric constant and slightly increased the thermal conductivity as well as the mechanical strength due to the well-dispersed clay mineral platelets (Yeh et al., 2009). 

Chang, Y. W., Lee, D., and Bae, S. Y, 2006. Preparation of polyethylene-octene elastomer/ clay nanocomposite and microcellular foam processed in supercritical carbon dioxide. Polymer International 55 184-9. 

Mitsnnaga, M., Y. Ito, S. S. Ray, M. Okamoto, and K. Hironaka. 2003. Intercalated polycarbon-ate/clay nanocomposites Nanostructnre control and foam processing. Macromolecular Materials and Engineering 288 (7) (July) 543-548. doi 10.1002/mame.200300097. http //doi.wiley.eom/10.1002/mame.200300097. 

Cao X, James Lee L, Widya T, Macosko C. Polyurethane/clay nanocomposites foams processing, structure and properties. Polymer 2005 46 775-83. 

Surface Behavior. Most extraction processes deal with several phases. At the boundaries between these phases, an interface exists which can be populated with or depopulated of polymer. Situations in which the polymer should accumulate at the surface of one phase are 1. the flocculation of clays and fines or 2. the formation of foams, while situations in which the polymer should depopulate the surface of the phase boundary are 3 minimizing adsorption in mineral acid leaching or 4. minimizing surface tension with surfactants in oil recovery by miscible flooding.,... 

Kaolloid. [Evans Clay] Hydrated aluminum silicate reinforcing filler in NR, SR, latexes, resins, plastics color and processing aid used in coated materials, footwear, flooring, V-belts, rolls, belts, matting, molded and extruded goods, foam goods, o-iings, seals, sundries. 

Clays are considered detrimental to EOR processes that are based on the injection of chemicals, such as foam-forming surfactants, because clays provide a large amount of surface area for adsorption. Table VII shows a comparison of specific surface areas of some clays (97, 117, 118) and of the solids used in the adsorption experiments of Figure 15 (12, 119, 120). Figure 15 allows comparison of adsorption levels in Berea sandstone, which consists mainly of quartz and 6-8% clays, with adsorption on clean quartz sand. 

The process involves blending PPCO with a resin or its blend that is to be foamed. The blend is then heated to T > 300°C, sufficient to melt the principal resin and to decompose PPCO. Talc, wollastonite, clay, CaCOj or citric acid can be used as a nucleating agent. The densities of the molded articles were reduced by at least 50%. Most recently, foaming of the engeneering resims by supercritical CO was introduced. 

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