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In recent years, polymer clay nanocomposites have been attracting considerable interests in polymers science because of their advantages. There are many scientists who researched about this kind of material and demonstrated that when polymer matrix was added to little weight of clay, properties were enhanced considerably. Because clay is a hydrophilic substance so it is difficult to use as filler in polymer matrix having hydrophobic nature, so clay needs to be modified to become compatible with polymer. In this study, poly(ethylene oxide) was used as a new modifier for clay to replace some traditional ionic surfactants such as primary, secondary, tertiary, and quaternary alkyl ammonium or alkylphosphonium cations having the following disadvantages: disintegrate at high temperature, catalyze polymer degradation, and make nanoproducts colorific, and so forth. In order to evaluate modifying effect of poly(ethylene oxide), modified clay products were characterize d by X-ray spectrum. Then organoclay was used to prepare nanocomposite based on unsaturated polyester. Morphology and properties of nanocomposites were measure d by X-ray diffraction, transmission electron microscopy, tensile strength, and thermal stability. The results showed that clay galleries changed to intercalated state in the nanocomposites. Properties of nanocomposites were improved a lot when the loading of the organoclay was used at 1 phr.

BACKGROUND: In this study, we have fabricated a polymeric material (CNC/Im) consisting of cellulose nanocrystals (CNC) synthesized from Vietnamese rice husk biomass and imidazole (Im) dopant. Next, we propose a new approach to fabricate Nafion/CNC/imidazole (NCI) composite materials by mixing the CNC/imidazole hybrid into Nafion matrix using a very simple solution method, and then investigating the influence of CNC/Im on the properties of NCI membranes. RESULTS: Electrochemical impedance spectroscopy (EIS) analysis showed that the proton conductivity of the CNC/Im membrane depends on the linked molar ratio of Im to glucose units (denoted by the n index), and this value is higher than that of pure CNC by a factor of 6. Differential thermal analysis (DSC) showed that the value of the n index is around 1:17 with all the content ratios between CNC and Im. Next, we synthesized composite materials based on CNC/Im and Nafion 117 (NCI) and investigated the influence of CNC/Im on the properties of NCI membranes. The results demonstrated that proton conductivity of the NCI membranes changes according to the content of Nafion 117, and reaches the highest value of 6.19 × 10 −4 S m -1 with an Nafion 117/(CNC/Im) ratio of 2:1. It was observed that the CNC fiber bundles were surrounded by a polymer layer and no phase separation occurs in the scanning electron micrographs of NCI materials.CONCLUSIONS: These results indicate that the prepared NCI composites will be potential materials for eco-friendly fuel cell operating in low humidity conditions.

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