SYNTHESIS AND PYROLYSIS OF NOVEL POLYMERIC PRECURSOSRS TO TIC/AL2O3, TIN/AL2O3, AND ALN/TIN NANOCOMPOSITES

The reaction between furfuryl alcohol (FuOH) and the products obtained by hydrolyzing a mixture of Ti(O-n-Bu)4 and Al(O-sec-Bu)3 resulted in the formation of soluble polymeric solids. Pyrolysis of these polymers in argon yielded TiC/Al2O3 composites at 1250-1375-degrees-C; further heating the precursors to 1500-degrees-C in argon led to the formation of a new phase due to the reaction between C, Al2O3, and TiC. When these polymers were pyrolyzed in ammonia or nitrogen, a TiN/Al2O3 Or TiN/AlN nanocomposite was formed, depending on the concentration of FuOH in the polymers. All these composites exhibited a fine-grained microstructure and excellent homogeneity. Furthermore, the structure and pyrolysis chemistry of these polymeric precursors, as well as the microstructure of the pyrolysis products, were studied by FTIR, TGA, GC, XRD, SEM, TEM, STEM, Auger electron spectroscopy (AES), and elemental analyses.