DEVELOPMENT OF A NOVEL TECHNIQUE FOR MONITORING OF CO-2 GAS-FLOW RATES AS A BASIS FOR QUANTITATIVE-ANALYSIS OF POLYMER ADDITIVES USING DIRECTLY COUPLED SFE/SFC

A novel technique for accurately measuring CO2 gas flow rates has been used to develop a directly coupled SFE/SFC (supercritical fluid extraction/supercritical fluid chromatography) technique for quantitative analysis of additives in polymers. The apparatus measures the concentration Of CO2 in air at the FID and split restrictor outlets using an electroconductivity principle. Quantitative measurement of triacetin additive in Biopol (a biodegradable polymer) was made. Studies of Irganox 1076 and 1010 additives in polypropylene showed some selectivity of the method over the higher molecular weight additive 1010 which has a molecular weight over 1100.