The Organic Particulate Thermal Analysis (OPTA) of Amine Arenesulfonates,Malonic Acids,and Metal Acetylacetonates

Abstract

The new technique of organoparticulate thermal analysis (OPTA) has been used to investigate the thermal decomposition reactions of various types of organic compounds (i.e., malonic acids, metal acetylacetonates, arenesulfonic acids and their amine salts). With a few exceptions, most of the compounds in these classes exhibit strong organoparticulation characteristics at temperatures below 200°C as indicated by their influence on the output current of an ion chamber detector.

In general, no direct correlation between the melting and decomposition temperatures and their organoparticulation temperature ranges (OPTR) was evident. In several instances, the OPTR values lay well above or well beneath the known melting point and decomposition temperatures of the compounds.

To explain the organoparticulating properties of these compounds, vapor phase association of polar molecules (such as amines, carboxylic acids, etc.) would appear to be necessary to give organoparticulate sizes detectable with the present instrumentation. Alternatively, the formation of an “aerosol” suspension of organic molecules in gases, such as SO₂, CO₂, might be occurring with some of these compounds