CRTA FOR THE THERMOANALYTICAL SCREENING OF VOLATILE COMPOUNDS 2 - THEVOLATILITY OF TRIFLUOROACETYLACETONATES OF AL, CR AND ZR STUDIED BY THE METHOD OF QUASI-EQUILIBRIUM THERMOGRAVIMETRY

Quasi-equilibrium thermogravimetry (with sample holders specially cali brated for the vapour pressure) was used for thermoanalytical screenin g of volatile compounds. 'p-T' relationships (in the range 0.0006 to 0 .11 at) were obtained for acetylacetonates and fluoroacetylacetonates of Al, Cr and Zr. The incorporation of the trifluoromethyl group into the acetylacetone ligand noticeably increases the volatility: the enth alpy of evaporation remains practically constant, but the evaporation entropy changes distinctly.