Abstract
We study pore nucleation in a model membrane system, a freestanding polymer film. Nucleated pores smaller than a critical size close, while pores larger than the critical size grow. Holes of varying size were purposefully prepared in liquid polymer films, and their evolution in time was monitored using optical and atomic force microscopy to extract a critical radius. The critical radius scales linearly with film thickness for a homopolymer film. The results agree with a simple model which takes into account the energy cost due to surface area at the edge of the pore. The energy cost at the edge of the pore is experimentally varied by using a lamellar-forming diblock copolymer membrane. The underlying molecular architecture causes increased frustration at the pore edge resulting in an enhanced cost of pore formation.
- Received 17 November 2015
DOI:https://doi.org/10.1103/PhysRevLett.117.257801
© 2016 American Physical Society
Physics Subject Headings (PhySH)
Focus
Membrane Holes Can Shrink, Grow, or Stay Put
Published 16 December 2016
Pores in a polymer film do not change size over time if they have just the right diameter, according to experiments.
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