| Abstract
| - Chemically functionalized alumina nanoparticles (carboxylate-alumoxanes) are used asthe inorganic component of a new class of inorganic−organic hybrid materials. Lysine- orp-hydroxybenzoic acid-derivatized alumoxanes are readily prepared from the reaction ofboehmite, [Al(O)(OH)]n, with the appropriate carboxylic acid. The peripheral organichydroxides and amines of these carboxylate-alumoxanes either react directly with epoxideresins, such as the diglycidyl ether of bisphenol A (DER 332), to form a hybrid material, orin the presence of an organic resin and hardener system to form a composite material. SEMwith associated EDX analysis, and AFM shows a uniform distribution of alumina nanoparticles within the resin matrix. Solid-state 13C and 27Al NMR spectroscopy demonstrates thatthe carboxylate-alumoxane nanoparticles are chemically bound to the epoxide resin matrix.The model compounds PhOCH2CH(OH)CH2OPh (1), PhOCH2CH(OH)CH2NHnPr (2), andPhOCH2CH(OH)CH2NHiPr (3) have been prepared to assist in the NMR characterizationof the hybrid materials. The properties and cure times of the alumoxane hybrid and compositematerials are distinct from both the pure resins and from a physical blend of the resinswith traditional ceramic fillers. A significant increase in thermal stability and tensile strengthis observed for both the hybrid and composite resin systems. In addition, both carbon fiberand carbon/Kevlar matting have been successfully incorporated into the hybrid resin systemsresulting in further property improvements.
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