| Nanocomposites are a relatively new class of materials, which exhibit ultrafine phase dimensions, typically in the range 1-100nm. Because of their nanometer –size disperson, the nanocomposites exhibit markedly improved properties when compared with the pure polymers or conventional composites. Nanoscale layered clays with very high aspect ratios and high strength can play an important role in forming effective polymer nanocomposites owing to their intercalation chemistry. Montmorillonite has been particularly important in polymer nanocomposites. Montmorillonite(MMT) belongs to the general family of 2︰1 layered silicates. Montmorillonite is a crystalline in which a central alumina octahedral sheet is a sandwiched between two silica tetrahedral sheets. When the nanoparticals are dispersed in the polymer matrix, two types of nanocomposites structures can be obtained. Intercalated nanocomposites are formed when there is limited inclusion of polymer chain between the clay layers with a corresponding small increase in the interlayer spacing of a few nanometers. On the other hand, exfoliated structures are formed when the clay layers are well separated from one another and individually dispersed in the continuous polymer matrix. Because exfoliated nanocomposites have higher phase homogeneity than the intercalated counterpart, the exfoliated structure is more desirable in enhancing the properties of the nanocomposites. The possibility of making nanocomposite materials with layered silicate clays in thermoset polymer resins is relatively unexplored. It has been reported in the patent literature that the dispersion of montmorillonite particles improved the mechanical properties of an amine-cured epoxy resin only slightly. Previous study reported the synthesis of diglycidyl ether of bisphenol A(E51) /montmorillonite nanocomposites. It has been demonstrated that the feasibility of dispersing molecular silicate layers within a macromolecular matrix, results in significant improvements in physical properties. Thus, it seems that a great need still exists for the development of a nanocomposite with other epoxy resin. Therefore, the present paper is directed to prepare the biphenol epoxy resin with tetra-methyl(TMBP)-MMT nanocomposites in an attempt to improve the physical properties. Also, the structure and the morphological hierarchy of its nanostructure are studied. In addition, the epoxy resin/montmorillonite nanocomposites were characterized by FTIR, XRD, SEM and impact and tensile tests.In chapter two, we disposed of Ca-montmorillonite with CH3(CH2)15N(CH3)3Br so as to low the cost of treating montmorillonite. FTIR of organ-montmorillonite shows that these positive charges such as Ca2+ have been exchanged with hexadecylamine. We get the X-ray diffraction patterns from the montmorillonite and organ-montmorillonite. The interlamellar spacing of the clay, corresponding to the (001) plane peak, increases from 1.49nm for the purified montmorillonite to 2.21 n m for the organ-montmorillonite. The interlamellar spacing of the clay increases to 2.99nm after curing in the end . The results of the study show that the intercalation nanocomposite materials have be formed. In chapter three, we chose the biphenol epoxy resin with tetra-methyl(TMBP) which was synthesized by our laboratory to synthesize epoxy resin/montmorillonite nanocomposites, compared with diglycidyl ether of bisphenol A( E 51) /montmorillonite nanocomposites. In the thesis,we used the amide curing agents DDM,DDS to study the curing performance, contrast with new type amide curing agents BADK which was synthesized by our laboratory. We first studied the cure kinetics of epoxy resin to sure the curing reaction condition. The results of the study show that the sequence of the melt point of three curing agents above is DDS>BADK>DDM, on the contrary, the sequence of the reaction activation is DDM>BADK>DDS, which is relative with molecular structure. Structures of nanocomposites were investigated by X-ray diffraction (XRD). The results of the study show that amide curing agents cured the biphenol epoxy resin with tetra-methyl...
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