COMPARISON OF SAMPLE CONCENTRATION METHODS AND CORRELATION CHROMATOGRAPHY FOR POLYMER DYNAMIC HEADSPACE STUDIES

Gas chromatography has been used to study the kinetics of evolution of volatiles from polypropylene samples (at 70 degrees C). Correlation chromatography (CC) and the trapping of volatiles on Tenax sorbents and activated charcoal were employed to improve the detector signal. As a reference, the kinetics of gas evolution was studied by making a series of direct single injections of polymer head-space gas on a GC column. The results of trapping differed from those obtained by single injection. However, the data from single injections and CC were in good agreement. The CC method was found to offer far more operator convenience for dynamic head-space analysis than sample trapping, being less subject to operator errors.