Polyolefin Resin Grade Verification via Attenuated Total Reflectance Spectroscopy
ATR-FTIR verifies polyolefin grades by measuring specific infrared absorbance ratios to quantify comonomer content, branching density, and copolymer structure.
Erucamide Slip Additive
Meaning
Fatty acid amide compound incorporated into polyolefin resins to reduce the coefficient of friction of extruded films. An erucamide slip additive migrates to the surface of the polymer as it cools, forming a microscopic lubricating layer that prevents film layers from sticking together. This migration continues until a state of equilibrium is reached between the bulk resin and the surface.
Surface Migration
The rate of additive movement depends on the crystallinity of the host polymer. In highly crystalline polyethylene, the erucamide slip additive moves quickly because the dense molecular structure forces the amide out of the polymer matrix. High storage temperatures accelerate this exudation process.
If the film is stored in hot warehouses, the additive can build up excessively and cause printing or sealing failures.
Friction Reduction
Sliding resistance between film layers during high-speed packaging causes processing bottlenecks. Introducing the erucamide slip additive lowers the coefficient of friction from over zero point six to below zero point two. This change allows smooth transport over metal forming collars and sealing jaws.
The lower friction prevent scuffing and tear defects in the finished package.
Processing Interface
Excessive additive migration can interfere with secondary conversion processes. The presence of the erucamide slip additive on the surface can reduce the adhesion of inks and lamination adhesives. This requires careful balancing of slip levels.