The intercalation of organically modified montmorillonite (OMMT) in the polymer blend of poly(ethylene oxide) (PEO) and poly(methyl methacrylate) (PMMA) has been demonstrated using dichloromethane as the cosolvent at room temperature. X-ray diffraction has been used to confirm the formation of nanoscale polymers-OMMT hybrids and the localization of the polymers between the organosilicate layers. The silicate nanocomposites have higher tensile modulus and elongation at break than the polymer matrix, revealing the dispersion of the clay particles in the polymer matrix. The specific interaction between the components was quantified by the Flory-Huggins interaction parameters, B, for pairs, determined by combining the melting point depression and the binary interaction model. The estimated B values for the binary PMMA/OMMT and PEO/OMMT pairs were all negative, showing both proper intercalation of the polymer into the gallery of OMMT and the homogeneous dispersion of OMMT in the polymer matrix. The B value for the PMMA/OMMT pair was smaller than that measured for the PEO/OMMT pair, suggesting that PMMA had better affinity for OMMT than PEO.

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Polyaniline-Na + -montmorillonite nanocomposite particles were synthesized using an emulsion intercalation method, and electrorheological (ER) fluids were produced by dispersing the synthesized nanocomposite particles in an electrically-insulating silicone oil. The emulsion of an aniline monomer with dodecyl benzenesulfonic acid was inserted into the layers of clay, and polymerization was processed by adding the oxidant initiator solution. DBSA as a emulsifier and a dopant took a important role for polyaniline clay nanocomposite. This insertion of polyaniline was confirmed by Xray diffraction. To observe its ER properties, we measured the shear viscosity and the shear stress by controlling shear rate. Furthermore, we conducted dynamic tests to investigate the viscoelastic properties of the ER fluid under an electric field in the linear viscoelastic region.

Styrene-acrylonitrile copolymer (SAN)/clay nanocomposites were synthesized through an emulsion copolymerization of styrene and acrylonitrile in the presence of sodium montmorillonite, and their physical properties and electroresponsiveness under an applied electric field were characterized. Thermogravimetric analysis (TGA) showed that the thermal stability of the synthesized polymer was sustained. X-ray diffraction (XRD) analysis confirmed the insertion of SAN into the interlayers of clay, whose separation consequently increased, as compared to those of the pristine clay. Transmission electron microscopy (TEM) was used to observe the suspended state of clay. Dry-base electrorheological (ER) fluids were prepared by mixing intercalated SAN nanocomposite particles into silicone oil. Typical ER behavior, i.e., enhancement of shear and yield stresses in the presence of an applied electric field, was observed using a rotational rheometer equipped with a high-voltage generator. A universal yield stress scaling equation was also found to fit our experimental data well.

Polyaniline (PANI) and its various copolymers were synthesized using different monomers such as o-methyl-, o-methoxy-, o-ethyl-, o-ethoxyaniline and sodium diphenylamine sulfonate by the chemical oxidation polymerization as air-stable organic conducting polymers, and adopted as one of the most potential materials of electrorheological (ER) fluids, especially for the anhydrous system. A relatively low density, a controllable conductivity, and thermal stability are advantages of the PANI based ER system compared with other ER materials. An FT-IR analysis was adopted to confirm their synthesis and a scanning electron microscopy (SEM) analysis indicated the shape of PANI derivatives was irregular. The effect of functional group of PANI on electric and electroresponsive properties of poly(aniline-co-ethoxyaniline) (COPA) particles were examined. A universal scaling equation of the yield stress was applied to these ER fluids and it was found that all data were collapsed successfully onto a single curve regardless of monomer type of the polyaniline synthesized. EXPERIMENTALThe PANI and its derivatives were synthesized through chemical oxidation polymerization by feeding different monomers using the modified method. [23][24][25] Non-ionic as well as