An active film prepared from waterborne polyurethane incorporated with different concentrations of butylated hydroxytoluene (BHT) and a-tocopherol was developed, and the films antioxidant characteristicswere studied using soybean oil as food model. The release behavior of additives from such films wasstudied using isooctane as a simulant fatty food. Antioxidant activity of the films into soybean oil at three
experimental conditions was monitored by FT-IR spectroscopy. Induction time and the kinetics of the oxidation process were followed using different bands of the FT-IR spectra. Films incorporated with 2 wt.% of BHT or a-tocopherol showed enough antioxidant activity to preclude oil oxidation during 60 days at 60 C in the dark. The results showed that this type of active films could be used for food preservation
as part of a packaging containing oils or oily related products.