Control of the migration behavior of slip agents in polyolefin‐based films

Unsaturated long‐chain carboxylic acid amides like Erucamide are very efficient as slipping agents in polyolefin films and other polymers. A problem is the uncontrolled migration of this additive. The main goal of the present project was therefore the study and understanding of Erucamide diffusion through the film and how the diffusion behavior can be altered using plasma surface treatments or additional additives with varying molecular weights and hydrophilic–hydrophobic balance. The determination of the amount of Erucamide and co‐additive at the surface of the polymer film has been carried out by attenuated total reflectance (ATR) spectroscopy. The study shows that the system is highly sensible to the chemical structure of the surface modifier and particularly their hydrophilic–hydrophobic balance and their molecular weight. The most efficient surface modifier tested in this work was a block‐co‐oligomer with 50% polyethylene (PE) and 50% polyethylene oxide (PEO) sequences that can successfully be used to reduce Erucamide migration at both sides of the three‐layer‐PE‐films. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers