Slip Additives: Enhancing Surface Smoothness and Processability in Plastics and Films
Slip additives are internal lubricants incorporated into plastic films, coatings, and inks to reduce surface friction and improve handling properties. They function by migrating to the surface of the polymer over time (a process called blooming or exudation) to form a thin, lubricating layer. The most common chemistry for polyolefin films like polyethylene (PE) and polypropylene (PP) is fatty acid amides, particularly erucamide and oleamide. These additives have a polar amide head that has an affinity for the polymer and a long, non-polar hydrocarbon tail that orients outward, creating a slippery surface. The concentration used is very low, typically between 0.05% and 0.3% by weight, as excessive amounts can cause unwanted haze or processing issues.
The primary application for slip additives is in the flexible packaging industry for food, consumer goods, and industrial products. They are essential for enabling high-speed packaging operations on form-fill-seal (FFS) machines, where low friction prevents…