Effect of Free Chain Oils on Adhesion of PDMS Elastomers

The creation of soft coatings that enable surfaces to easily shed solids like ice or biofoulants is a major goal for industrial applications. One way to minimize adhesive forces is to infuse an elastomer with an oil (free polymer chains). However, there is no current framework to understand what oils and at what concentrations are optimal as there is not a complete physical picture of the system. To test the effects of oils in an elastomer network on adhesion and viscoelastic losses, we use several in-house polydimethylsiloxane-based elastomers and several different silicone oils. The oils vary in their compatibility, molecular weight, and chemical makeup. Tension adhesion tests are performed, and then analyzed using the Johnson-Kendall-Roberts model revealing the rubbery regime modulus and speed dependent energy release rate (adhesion strength). The dynamic modulus is measured using dynamic mechanical analysis experiments for temperatures ranging from 100 Celsius to the glass transition temperature. Ultimately, the measured energy release rates are compared with model results from models proposed by Persson and Brener [2], Barthel and Fretigny [1], Saulnier et al. [3], and Schapery [4].



[1] Barthel, E., & Frétigny, C. (2009). Adhesive contact of elastomers: effective adhesion energy and creep function. Journal of Physics D: Applied Physics, 42(19), 195302.

[2] Persson, B. N. J., & Brener, E. A. (2005). Crack propagation in viscoelastic solids. Physical Review E—Statistical, Nonlinear, and Soft Matter Physics, 71(3), 036123.

[3] Saulnier, F., Ondarçuhu, T., Aradian, A., & Raphaël, E. (2004). Adhesion between a viscoelastic material and a solid surface. Macromolecules, 37(3), 1067-1075.

[4] Schapery, R. A. (2022). A theory of viscoelastic crack growth: revisited. International Journal of Fracture, 233(1), 1-16.