| Dispersedness of montmorillonite(MMT) in polymer is the key to preparation of the high-powered MMT / polymer nanocomposite. However, most of the researches just focus on the preparation of nanocomposites and the improvement of the performance, much more comprehensive and further work need to be done. In our work, MMT / epoxy(EP) nanocomposites made by intercalation was chosen to study the intercalation process ,exfoliation mechanism, dispersedness of MMT and its properties and the curing reaction kinetics, etc.First, intercalation and exfoliation behaviors of organ clays in epoxy resin has been investigated by XRD. It was found that the intercalation and exfoliation ability of organ clays was basically determined by the intercalation reagent used, also determined by the properties of curing reagent and conditions of blending and curing.The exfoliation mechanism was discussed. The results revealed that if the montmorillonite was exfoliated, both the thermodynamics condition and the dynamics condition were all fulfilled. As the heat of epoxy curing reaction calculated exceeded exfoliation impetus of montmorillonite, the driving force of montmorillonite exfoliation is the polymerization energy released by the curing reaction. In addition, the dynamics condition was needed for the exfoliation. The exfoliation of montmorillonite was laid on the competition of the curing of the intra-gallery resin with the curing of the extra-gallery resin. If the intra-gallery epoxy cured faster, it will drive the clay to exfoliate before the extra-gallery epoxy resin reaches its gel point. Otherwise the extra-gallery epoxy resin will gel firstly and block the further exfoliation of the clay. So the factors facilitating the curing of the intra-gallery epoxy would enhance the exfoliation of organ clays.Secondly, three montmorillonite / epoxy composites were prepared as filled composite, intercalated composite and exfoliated composite. The mechanism properties results indicated that the exfoliation of organ clay in epoxy resin was essential for enhancing properties of nanocomposites. It was indicated that intensity and toughness was increased by the exfoliation of organ clays in epoxy resin, and the heat-resistant property was also increased significantly. When the content of the organ clay was 2 wt %, the properties of exfoliated composite reached the optimum.Lastly, the curing reaction kinetics of E-51 and DK2 cured by 2-ethyl-4-methyl imidazole (M-Q) was investigated by DSC. The curing technical parameters werederived; it was found that the curing temperature of composite was descended by DK2. Synchronously the. activation energy of DK2 / EP / M-Q calculated by Kissinger equation and Crane equation was lower than the activation energy of EP / M-Q. Acid catalysis mechanism model of DK2 to epoxy curing was elementarily set up, thevelocity equation of this curing reaction was obtained: . Thedtmechanism model was validated by isothermal DSC experiments , the activation energy calculated was decreased by the content of DK2 increased , Ea of pure epoxy/ M-Q was 79.92 kJ/mol , and Ea of 15 % DK2 / EP / M-Q was 51.95 kJ/mol ,above judgment was testified .On the basis of the above researches on the exfoliation and dispersedness of MMT, properties and the curing reaction kinetics, an approach that using chemical reaction in the tiny intra-gallery to dis-coalesce the nano-reunite was proposed to explain the immanence driving force of the exfoliation of MMT both in nano-layered silicates and in nanoparticles .
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