Simultaneous Determination of Antioxidants and Ultraviolet Stabilizers in Polyethylene by HPLC

Abstract

A simple and simultaneous determination method was developed for 18 kinds of antioxidants and 10 kinds of ultraviolet stabilizers in polyethylene. Additives were extracted with a mixed solution of cyclohexane and 2-propanol (1:1) by soaking overnight at 37°C and purified by concentration and redissolution in warm acetonitrile. They were then analyzed by reversed-phase HPLC with UV detection at 225nm. The mobile phase was a linear gradient from 3:2 acetonitrile-water to acetonitrile. The recoveries of 28 kinds of additives fortified at 20 and 100μg/g in polyethylene flakes ranged from 86.8-127.0% and 70.4-93.6%, respectively. The limits of quantitation were 2.0-10.0μg/g for each additive in polyethylene.