Peel Resistance
Maximum force required to separate two flexible substrates bonded together, applied at a right angle to the bond line, determines the durability of flexible packages and laminated pouches. The T-peel strength is measured by stripping the two arms of a T-shaped specimen apart in a tensile tester, with the results reported in Newtons per millimeter of width. This test is critical for determining the heat-seal and adhesive strength of thin films, metal foils, and light paper webs.
High values ensure that the pouch resists opening during shipping.
Failure Analysis
Results from this test can reveal the specific weak point of the laminated assembly by showing whether the separation occurs at the adhesive-substrate interface or within the adhesive layer. When a laminate shows low T-peel strength, it can indicate poor adhesive curing, incorrect coating weight, or insufficient surface treatment of the films. The profile of the force curve during the test provides valuable information about the uniformity of the adhesive application.
Analyzing these graphs helps to diagnose extruder or laminating roll inconsistencies.
Production Limits
Packaging lines require a minimum peel strength to ensure that the composite material holds together during high-speed bag-making and filling. This limit varies based on the product density and the severity of the filling-line drops.
