90 Degree Peel

The 90-degree peel test is a mechanical method used to measure the adhesive strength between two bonded materials. One substrate is peeled away from another at a fixed 90-degree angle while the force required to maintain separation is recorded. This produces a measure of peel strength and adhesion performance.

The test is commonly applied to pressure-sensitive tapes, labels, laminates, flexible films and bonded assemblies where reliable adhesion is critical. It is also widely used for packaging seals, insulation panels and engineered composites. By providing quantitative data, the 90-degree peel test enables manufacturers to ensure consistent quality, optimise adhesive formulations and comply with international standards.

Adhesion is fundamental in industries such as packaging, automotive, construction and electronics. A reliable adhesive bond ensures product integrity, safety and consistent performance.

The 90-degree configuration is particularly useful when one substrate is rigid and the other is flexible. Unlike the 180-degree peel test, which is suited to flexible-to-flexible joints, the 90-degree test maintains a constant angle where one component cannot bend. This makes it ideal for applications such as tapes applied to cartons, labels on containers and insulation panels bonded to rigid surfaces.

By analysing peel behaviour, engineers can identify adhesive failures at the bond line, cohesive failures within the adhesive itself or substrate delamination. This understanding supports material selection, product development and quality assurance programmes.

A standard 90-degree peel test involves four main steps:

• Specimen preparation - Bonded samples are prepared according to the chosen standard and conditioned under laboratory conditions, typically 23 °C and 50 percent relative humidity.
• Fixture and alignment - The specimen is mounted in a fixture designed to maintain a 90-degree peel angle during testing.
• Controlled peel - The test stand crosshead moves at a constant speed, commonly 300 mm per minute for pressure-sensitive adhesives, while maintaining the peel angle.
• Force measurement - A calibrated load cell records the peel force as the bond is separated. Results may be reported as average peel strength, peak force or displayed as a force-displacement curve.

Typical forces recorded in peel tests range from 5 newtons for light adhesives up to 200 newtons or more for structural bonds. These results provide engineers with measurable data on bond performance under controlled conditions.

Mecmesin provides a range of test systems designed for peel and adhesion applications:

• MultiTest-dV motorised test stands offer affordable and precise control of speed and movement, making them ideal for routine peel tests.
• MultiTest and OmniTest universal testers deliver advanced capability for higher force ranges, programmable routines and more complex testing requirements.
• 90-degree peel fixtures ensure that the peel angle remains constant throughout the test for repeatable and standardised results.
• VectorPro software captures and analyses data in real time, providing clear graphical displays, statistical outputs and automated reporting.

These systems are used across industries, from packaging and adhesives to insulation and electronics. Custom fixtures are available for unusual sample geometries. Examples include testing packaging seals for beverages to ensure consistent opening behaviour and evaluating the adhesion of insulation panels to verify durability in construction applications.

The 90-degree peel test is defined by several recognised international standards, which provide consistent methodology and reporting requirements:

• ASTM D6862-11 - Peel resistance of adhesives with rigid substrates.
• ASTM D6252 - Peel adhesion of pressure-sensitive tape.
• ISO 8510-1 - Determination of peel resistance of flexible bonded to rigid substrates.
• FINAT FTM 2 - 90-degree peel adhesion test for pressure-sensitive adhesives at a constant speed of 300 mm per minute.

Mecmesin equipment, fixtures and software are designed to comply with these standards, giving engineers confidence that their test results are accurate and repeatable.

The 90-degree peel test is an essential method for assessing adhesive performance in packaging, tapes, insulation and industrial applications. Mecmesin’s equipment provides engineers with precise, repeatable and application-specific results.

To discuss your requirements or to explore tailored solutions for peel and adhesion testing, speak to an expert at Mecmesin.