SYNTHESIS AND CHARACTERIZATION OF PRECURSORS FOR GROUP-II METAL ALUMINATES

Precursors to Group II metal aluminates (MAI(2)O(4), M = Mg, Ca, Ba, S r) are synthesized from inexpensive starting materials including Group II metal oxides/hydroxides, Al(OH)(3), triethanolamine (TEA) and ethy lene glycol, in a one-pot synthesis process, The precursors are solubl e in common organic solvents and can be handled in moist air for a rea sonable period of time, On pyrolysis in air to 1200 degrees C, all thr ee precursors transform to the corresponding Group II metal aluminates , A termetallic double alkoxide, 'ionomer-like' structure is proposed, wherein the alkalineearth metal is encapsulated by a TEA molecule bri dging two alumatrane units, The precursors were characterized using TG A, NMR, mass spectroscopy and elemental analyses, and the pyrolysed pr ecursors were briefly characterized using x-ray diffraction analysis. (C) 1997 John Wiley & Sons, Ltd.