Self-folding PDMS polymer films in response to capillary forces
Open Access
- Author:
- Stokes, Sean M
- Area of Honors:
- Engineering Science
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Melik C Demirel, Thesis Supervisor
Melik C Demirel, Thesis Supervisor
Dr. Gary L Gray, Thesis Honors Advisor
Judith A Todd Copley, Faculty Reader - Keywords:
- PDMS
self-folding
capillary forces
PPX
microfabrication
thin films
polymer films
directional folding
anisotropic folding - Abstract:
- Folding processes have proven to be highly beneficial in both nature and manmade devices for a variety of functions such as in protein folding, insect wing functionality, and spacecraft storage. On a micro-scale, folding can be a novel and effective method for fabrication of complex 3-D structures. At this scale, capillary and surface tension forces dominate over bulk body forces, which usually pose a serious threat to nano- and micro-structures due to the deformation of surface geometries. However, in a self-folding film application, these surface tension forces can be harnessed to drive fabrication of three-dimensional structures out of easily synthesized twodimensional patterns. In this study, the effectiveness of this mode of fabrication is examined through the folding of a variety of three-dimensional polydimethylsiloxane (PDMS) shapes out of thin (25-30 μm) sheets. Furthermore, the capability to directionally fold is investigated through the deposition of a poly-p-xylylene (PPX) surface layer to induce anisotropy to the PDMS surface. Theoretically, this will allow for controllability of the direction of folds.