Montmorillonite emulsion polymerized

Li, H., Yu, Y., and Yang, Y, Synthesis of exfoliated polystyrene/montmorillonite nanocomposite by emulsion polymerization using a zwitterion as the clay modifier, Eur. Polym. J., 41, 2016-2022 (2005). 

Voorn DJ, Ming W, Van Herk AM (2006) Polymer-clay nanocomposite latex particles by inverse Pickering emulsion polymerization stabilized with hydrophobic montmorillonite platelets. Macromolecules 39(6) 2137-2143... 

Montmorillonite (MMT) is natural candidate for formation of nanocomposite due to special lamellar structure. In particular, the absorbed cation in interlayer provides ions exchange ability for intercalation of positive charged aniline monomer in the acid solution. Several approaches have been proposed to attempt to obtain ER active material based on PANI-intercalated MMT (PANI-MMT) nanocomposite [94-96]. Kim et al. [94] have introduced for the first time a kind of PANI-MMT (PANI-Na -MMT) nanocomposites as ER material. PANI-Na -MMT nanocomposite particles have been synthesized via emulsion polymerization. In the preparation, Dodecylbenzenesulfonic acid (DBSA) is used to disperse aniline monomer in xylene and then the clay colloid is added to form emulsion. 

Parker et al. [49] altered the stabilization mechanism for styrene-butadiene latex prepared by emulsion polymerization from anionic to cationic so that they could get a spontaneous flocculation with aqueous montmorillonite slurry and the latex. Evaluation of the rubber nanocomposite prepared in this manner gave dramatic increases in modulus, strength, percent elongation, and decrease in hysteresis. 

Sun F, Pan Y, Wang J, Wang Z, Hu C, Dong Q. Synthesis of conducting polyanihne-montmorillonite nanocomposites via inverse emulsion polymerization in supercritical carbon dioxide. Polym Composite 2011 31 163-172. 

When the rubber is prepared by emulsion polymerization, e.g. SBR, or harvested as an aqueous emulsion (natural rubber NR), an effective process for preparing excellent rubber-montmorillonite composites consists of blending an aqueous dispersion of the montmorillonite with the aqueous polymer dispersion [61]. This dispersion is stable, because the stabilization mechanism (anionic stabilization) is identical for the latex and montmorillonite. This dispersion can be processed with the same... 

The research around the use of montmorillonite to obtaining nanocomposites polymer-MMT has become even more intense. In a review, Biswas and Ray [45] described several features of polymer-MMT nanocomposite materials. Ray and Okamoto [24] reported various characteristics of polymer-layered silicate nanocomposite materials, some of these materials exhibited distinctive properties like biodegradability. Ahmadi et al. [46] reviewed synthetic routes, properties, and future applications of polymer-layered nanocomposites. Significantly, nanocomposites of PAni and PPY with MMT clay via emulsion polymerization technique [47, 48] were found to act as electrorehological fluids, sometimes denominated smart fluids. In this context, Ballav and Biswas [49, 50] reported high yield oxidative polymerization of thiophene, aniline, pyrrole, and furan by MMT— without extraneous oxidant—vis-a-vis nanocomposites formation of the corresponding polymers with MMT. 

Mballa Mballa MA, Ali SI, Heuts JPA, van Herk AM (2012) Control of the anisoUopic morphology of latex nanocomposites containing single montmorillonite clay particles prepared by conventional and reversible addition-fragmentation chain transfer based emulsion polymerization. Polym hit 61 861-865... 

Greesh et al described an interesting study on the effect of clay surface modification on the microstructure and properties of polymer-clay nanocomposites synthesized by using free radical emulsion polymerization. Copolymers of styrene and butyl acrylate were synthesized in the presence of montmorillonites modified with various surface modifiers in order to relate their chemical structure, degree of interaction within the clay gallery surface... 

Diaconu et alJ also reported the use of pristine sodium montmorillonite for the synthesis of very high solids poly(methyl methacrylate-ct -butyl acrylate) latexes by using seeded emulsion polymerization. Figure 1.11 shows the particle size distributions for the various latexes synthesized without or with clay following different synthetic methodologies. For the pure polymer latex (EPl), the distribution was unimodal and narrow. However, for the nanocomposite latexes, the distributions were broad and tended to have shoulders towards the... 

Yei et al7 described the synthesis of polystyrene-clay nanocomposites using emulsion polymerization and specifically modified montmorillonite. Two different surface modifications were used to organophilize the montmorillonite, with cetylpyridinium chloride (CPQ and the CPC-a-cyclodextrin (CD) inclusion complex. Glass transition temperatures of 102 and 106 °C were observed for CPC-clay and inclusion complex lay nanocomposites, compared with 100 °C for pure polystyrene. 

Emulsion polymerization and suspension polymerization have been widely studied to promote intercalation of water-insoluble polymers into layered silicates such as montmorillonite, which is well known to delaminate readily in water owing to the weak forces that stack the layers together. The... 

PMMA-based Montmorillonite Nanocomposites by Soap-free Emulsion Polymerization... 

The polymer-clay nanocomposites with core-poly(butyl acrylate) (PBA) intercalated organophilic montmorillonite (OMMT) and shell-PS were successfully prepared using y-irradiation emulsion polymerization by Wang et al., as shown in Figure 8.3. The prepared core-PBA-OMMT and shell-PS structure nanocomposites can be incorporated in a pure PS matrix the impact strength of the blend was dramatically improved and the tensile strength of PS also remained high. 

Among the variety of inorganic solids e.g. silica, iron oxides, titanium dioxide, metals), clay minerals have recently attracted considerable attention. Indeed, polymer-clay nanocomposites (PCNs) have been the topic of extensive research worldwide since scientists at the Toyota Central Research laboratories reported 10 years ago that the incorporation of small amounts of montmorillonite (MMT) into nylon-6 resulted in a remarkable enhancement of the thermal and mechanical properties of the nanocomposite material. Whereas there has been a tremendous number of studies on the synthesis, properties and applications of polymer-clay nanocomposites in the recent literature, surprisingly only a small number of reports have dealt with emulsion polymerization. 

Wang ° used two different organic modifications of the montmorillonite, one contains a styryl monomer on the ammonium ion while the other contains no double bond. A double bond that may be involved in the polymerization reaction is present in the cation of the clay. Polystyrene-clay nanocomposite has been prepared by bulk, solution, suspension, and emulsion polymerization as well as by melt blending. The organic modification as well as the mode of preparation may determine whether the composite is either exfoliated or intercalated. Exfoliation is more likely to occur if the ammonium ion contains a double bond... 

F.M. Uhl, S.P. Davuluri, S.C Wong, D.C Webster, Organically modified mont-morillonite in UV-curable urethane-acrylate films , Polymer, 2004, 45, 6175-6187. J.Y. Kim, W.C Jung, K.Y. Park, K.D. Sub, Synthesis of Na montmorillonite/ amphilitic pol3Tirethane nanocomposite via hulk and coalescence emulsion polymerization , J. Appl. Polym. Sci., 2003, 89, 3130-3136. 

Conducting polymers such as PANl- or PPY-intercalated clay-type minerals are another type of ER particle material. Kim et al. synthesized PPY-intercalated montmorillonite nanocomposites through inverted emulsion pathway polymerization, and characterized its ER effect under an electric field [38]. The nanocomposites showed not only a typical ER behavior under electric fields but also the existence of a critical electrical field when the yield stress was plotted as a function of the electric field. 

Yang et al reported the emulsion and suspension polymerization of styrene in the presence of montmorillonite modified with various modifying agents such as cetyltrimethylammonium chloride, cetylpyridinium bromide. 

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