Plastic Testing Case Studies:
Heat Seal Adhesive Failure Analysis
Our client’s new heat seal adhesive was not providing a hermetic seal and released after only a few days. Faced with production line shut-down and delayed shipments, the customer called EAG. They suspected that the new adhesive’s formula, a polyurethane-acrylic hot melt adhesive, was the reason for the failure. Our expert chemists deformulated both the old formula and the new formula. The results showed significant differences in the molecular weight and molecular weight distribution, as well as the urethane-acrylic ratio. After concluding that these variations were the reason for the adhesion failure, we recommended a formula adjustment. The revised formula performed well, and the customer was able to resume operations.
The Sky is Falling
A manufacturer of light fixtures received complaints about fluorescent tubes falling out of overhead light fixtures. The failed fixtures showed large fractures in the plastic components that held the fluorescent tubes in place. There was also a white powdery residue on the plastic components. Our scientists identified the white residue, confirmed the composition of the failed plastic components and in discussions with the manufacturer, determined that the white residue was from chemicals used in the facility where the failures occurred. The chemical giving the white residue was reacting with the plastic components and breaking down the structure of the polymer. This information helped the manufacturer take proper corrective action.