Experiments on contact of a loop with a substrate to measure work of adhesion

• Published in: The Journal of adhesion 2003-06, Vol.79 (6), p.559-579
• Main Authors: Qi, Jia, Dillard, David A., Plaut, Raymond H., Dillard, John G.
• Format: Article
• Language: English
• Subjects: Applied sciences; Contact Experiments; Elastica; Exact sciences and technology; Finite Element Analysis; Inorganic and organomineral polymers; Jkr Technique; Loop; Physicochemistry of polymers; Properties and characterization; Surface Energy Of Solids; Work Of Adhesion
• ISSN: 0021-8464; 1563-518X; 1545-5823
• DOI: 10.1080/00218460309543

A technique for characterizing surface energies of solid materials is investigated experimentally and numerically. A narrow strip is bent into a loop, pushed into contact with a flat substrate, and then pulled off the substrate. Provided the loop is sufficiently flexible, the size of the contact zone during this process was expected to depend on the interfacial interactions. Larger adhesion forces should tend to increase the contact size, in a manner analogous to the JKR technique. The experiments involve a poly (dimethyl siloxane) (PDMS) loop and glass substrates with various coatings. Anticlastic bending of the loop affects the contact zone. Hysteresis is observed between the loading and unloading data. A three-dimensional finite element analysis is conducted in which adhesion forces are not included, and results from a two-dimensional elastica model of the loop are utilized for comparison purposes. The contact zone appears to be insensitive to the adhesive interactions between the loop and the substrate for the systems studied.