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.
Solventless Lamination Bond Strength
Laminate Cohesion
Adhesive film metric in flexible packaging determines the mechanical resistance of laminated layers to peel forces during storage and use. Measuring solventless lamination bond strength ensures that the multi-layer barrier films will not separate when subjected to high temperatures or product chemistry. This quality check is performed on a tensile tester to ensure the adhesive has cured properly and anchored the layers together.
Adhesive Curing
Developing a strong bond requires the two-component polyurethane adhesive to cross-link completely over a period of several days. If the mixing ratio is incorrect or the curing temperature is too low, the laminate will fail to achieve its full potential strength. The presence of slip agents or moisture on the film surface can also inhibit the chemical reaction, resulting in a weak or spotty bond.
Performance Evaluation
Checking the strength of the bond involves pulling the layers apart at a constant speed and measuring the force required to peel them. The results are compared to the minimum standards required for the intended application, such as retort processing or dry food storage. High-performance films require higher peel values to prevent package failure when exposed to acidic foods or high pressure during sterilization.
In many cases, the bond is so strong that the film itself tears before the adhesive layer separates.