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arXiv · 2404.18129

Stability and Elasticity of Ultrathin Sphere-Patterned Block Copolymer Films

Le Qiao·Daniel A. Vega·Friederike Schmid
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Abstract

Sphere-patterned ultrathin block copolymers films are potentially interesting for a variety of applications in nanotechnology. We use self-consistent field theory to investigate the elastic response of sphere monolayer films with respect to in-plane shear, in-plane extension and compression deformations, and with respect to bending. The relations between the in-plane elastic moduli is roughly compatible with the expectations for two-dimensional elastic systems with hexagonal symmetry, with one notable exception: The pure shear and the simple shear moduli differ from each other by roughly 20%. Even more importantly, the bending constants are found to be negative, indicating that free-standing block copolymer membranes made of only sphere mono-layer are inherently unstable above the glass transition. Our results are discussed in view of experimental findings.

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Le Qiao, Daniel A. Vega, Friederike Schmid. 2024-04-28. Stability and Elasticity of Ultrathin Sphere-Patterned Block Copolymer Films. https://doi.org/10.1021/acs.macromol.4c00460

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