Quantifying Surface Energy Values on Polyolefin Packaging Materials
Polyolefin surface energy quantification relies on standardized liquid titration or goniometry to secure ink adhesion and lamination bond strength across runs.
Erucamide Slip Agent Migration
Surface Migration
Additive transport within polymer layers changes the surface friction of packaging films as the material cools after extrusion. The process of erucamide slip agent migration involves the movement of fatty acid amides from the internal matrix of the film to the outer surface. Once on the surface, these molecules align to form a thin, microscopic lubricant layer that reduces the coefficient of friction.
Friction Control
Slip performance depends on the concentration of the additive and the crystallinity of the surrounding polymer matrix. If the migration happens too quickly, the excess lubricant can interfere with corona treatment and the adhesion of printing inks. Conversely, insufficient migration results in high friction that causes film wrapping on rollers or jamming on high-speed packaging lines.
Packaging Application
Managing the migration rate requires balancing storage temperatures and additive loading during the masterbatch formulation process. Cold storage conditions slow down the movement of molecules. Elevated temperatures accelerate their journey to the film surface.
When multi-layer co-extrusion is used, the slip agent is often confined to specific layers to prevent migration to surfaces where lamination or printing is planned. This directional control ensures that the film retains high bond strength during lamination while still sliding easily over metal forming collars on vertical form-fill-seal machines.