EN 1939 is used to measure the peel adhesion properties of self-adhesive tapes. The adhesive materials are cut into 24 mm wide specimens and peeled away from the substrate at a 180° angle. EN 1939 is divided into four sections, which describe the adhesion to stainless steel, to backing material, to a liner, and for double-sided tape. The standard also describes methods to perform the peel at low temperatures and at a 90° angle. The test results in a peel strength, generally presented in an average load divided by the specimen width.
The challenges of testing to this standard are:
- Compliance with the standard
- Data rate used to capture peaks and troughs
- Gripping materials of varying thickness
- Eliminating slippage throughout the test
- Compliance with the standard – Bluehill® Universal comes with pre-configured test methods and supporting documentation to ensure that you are testing according to EN 1939.
- Data rate used to capture peaks and troughs – Instron’s 5900 series frames enable data capture of up to 2.5 kHz to ensure that all fast changing test events are captured. Too low of a bandwidth may “dull” the system and lead to missed peaks and troughs, resulting in lower average strength values.
- Gripping materials of varying thickness – When testing an adhesive to a thick substrate, standard grips can result in a misaligned specimen. The advanced screw action grips can be adjusted and offset to ensure that the specimen remains centered in the load string.
- Eliminating slippage throughout the test – The advanced screw action grips employ a patented “quick-change” jaw face design which enables operators to easily change jaw faces to accommodate the needs of their materials. Pneumatic grips can also be used for thinner substrates and are able to maintain consistent gripping pressure throughout the test.