Swelling-Induced Delamination Causes Folding of Surface-Tethered Polymer Gels
Abstract
When a polymer film that is weakly attached to a rigid substrate is exposed to solvent, swelling-induced compressive stress nucleates buckle delamination of the film from the substrate. Surprisingly, the buckles do not have a sinusoidal profile, instead, the film near the delamination buckles slides toward the buckles causing growth of sharp folds of high aspect ratio. These folds do not result from a wrinkle-to-fold transition instead, the film goes directly from a flat state to a folded state. The folds persist even after the solvent evaporates. We propose that patterned delamination and folding may be exploited to realize high-aspect ratio topological features on surfaces through control of a set of boundary constraints arising from the interrelation of film-surface adhesion, film thickness and degree of swellabilty.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 26, 2011
- Accession Number
- ADA577356
Entities
People
- Richard A. Vaia
- Sachin S Velankar
- Victoria Lai
Organizations
- Air Force Research Laboratory