Migration of Erucamide in Polyethylene Film

ABSTRACT Erucamide is a migratory slip agent widely used in polyethylene (PE) films for flexible packaging applications, particularly those processed on high‐speed filling and packaging lines, where control of the coefficient of friction (COF) is critical; however, its uncontrolled migration can adversely affect surface and processing properties. In this study, the migration behavior of erucamide in a three‐layer low‐density polyethylene (LDPE) film was investigated as a function of aging time and storage temperature, and its impact on COF and sealing behavior were evaluated. The film was characterized by differential scanning calorimetry (DSC), x‐ray diffraction (XRD), and thermogravimetric analysis (TGA), confirming its LDPE composition. The erucamide concentration on prepared film was determined as 3500 ± 370 ppm by high‐performance liquid chromatography (HPLC). Crystallinity values obtained from DSC and XRD showed good agreement and were correlated with additive migration. Surface morphology, topographical changes, and slip‐agent distribution were analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM), while surface energy changes were assessed by contact angle measurements. Fourier transform infrared photoacoustic spectroscopy (FTIR‐PAS) confirmed the presence of erucamide near the film surface. A rapid decrease in COF with increasing temperature was observed. So, COF values after 72 h at room temperature were similar to the ones obtained at 50°C on just warmed films; however, excessive surface crystallization was observed at elevated temperature, leading to an increase in the initial sealing temperature. The combined analytical approaches proved effective in elucidating erucamide migration and its influence on film performance.