Abstract
Many soft materials, such as block copolymers and micelles, are characterized by a tunable organization that can be exploited for formation of nanostructures. In this work, drying patterns, formed when nanoparticle solutions are spin coated on ultrathin films of the block copolymer poly[styrene-b-ethylenepropylene] (PS-PEP), are investigated as a function of the film's organization. Prior to particle deposition, thermal annealing was used to adjust the polymer film organization between a layer of PS-PEP micelles (no annealing) and a bilayer with a uniform PEP 'polymer brush' layer on top of an underlying layer of PS (extensive annealing). For intermediately annealed films, ring-shaped drying patterns consisting of as few as 5 or as many as 30 nanoparticles are observed. The nanorings are polydisperse with a diameter between 15 and 50 nm, and cover macroscopic surface areas of the film. It is suggested that these rings form as a consequence of inhomogeneous drying of particle solutions due to heterogeneities in the film structure, as deposition of nanoparticles on extensively annealed, uniform films did not produce rings.
Original language | English (US) |
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Pages (from-to) | 1483-1488 |
Number of pages | 6 |
Journal | Nanotechnology |
Volume | 15 |
Issue number | 11 |
DOIs | |
State | Published - Nov 2004 |
ASJC Scopus subject areas
- Bioengineering
- General Chemistry
- General Materials Science
- Mechanics of Materials
- Mechanical Engineering
- Electrical and Electronic Engineering