Determination of Polyolefin Additives by Normal-Phase High Performance Liquid Chromatography following Soxhlet Extraction

Methods were developed for the determination of three classes of polyolefin additives. These classes are: mono and digly-cerides, tertiary C 12 -C 16 alkyldiethanolamines, and alkyldithiopropionates. Soxhlet extractions were performed on 50 g ground samples with chloroform for 2 hours. The extracts were concentrated and the additives were determined by high-performance liquid chromatography on a μ-Porasil stationary phase. The methods were studied with both polyethylene and polypropylene.