SYNTHESIS AND PROPERTIES OF AN ALUMINUM NITRIDE POLYIMIDE NANOCOMPOSITE PREPARED BY A NONAQUEOUS SUSPENSION PROCESS

A nanocomposite of a chemically synthesized nanostructured aluminum ni tride (AIN) and a polyimide has been studied. Using a nonaqueous polar solvent, N-methylpyrrolidinone (NMP), as the suspension media, the de gree of particle agglomeration of AlN was reduced dramatically from mi cron to nanoscale size. Upon the addition of poly(amic acid) to the Al N/NMP suspension, a further deagglomeration of the particles was obser ved. The surface physicochemical interactions have been investigated b y characteristic model reactions using FTIR spectroscopy. A mechanisti c interpretation for the deagglomeration and stabilization behavior is discussed. The formation of the AlN/PI nanocomposite was achieved by the rapid solidification of the precursor suspension followed by compr ession molding. Such an approach for nanocomposites exhibits better ho mogeneity with ultrafine fillers and allows a tailorable composition a nd property at the nanoscale level. Finally, AlN/PI nanocomposites wit h an increased ceramic loading, up to 65% by volume, were attained and their thermal and mechanical properties, along with the compositional effects, have been investigated.