Tuning the Dimensions and Periodicities of Nanostructures Starting from the Same Polystyrene‐block‐poly(2‐vinylpyridine) Diblock Copolymer

Abstract

The controlled tuning of the characteristic dimensions of two‐dimensional arrays of block‐copolymer reverse micelles deposited on silicon surfaces is demonstrated. The polymer used is polystyrene‐block‐poly(2‐vinylpyridine) (91 500‐b‐105 000 g mol–1). Reverse micelles of this polymer with different aggregation numbers have been obtained from different solvents. The periodicity of the micellar array can be systematically varied by changing copolymer concentration, spin‐coating speeds, and by using solvent mixtures. The profound influence of humidity on the micellar film structure and the tuning of the film topography through control of humidity are presented. Light scattering, atomic force microscopy, scanning electron microscopy, transmission electron microscopy, and X‐ray photoelectron spectroscopy were used for characterization. As possible applications, replication of micellar array topography with polydimethylsiloxane and post‐loading of the micelles to form iron oxide nanoparticle arrays are presented.

Aggregation Processes of a Weak Polyelectrolyte, Poly(allylamine) Hydrochloride

“…The experimental values were smaller than the theoretical, indicating the aggregated PAH (turbid state) exists as a structure with a well-defined domain rather than a random coil. [16][17][18] The Interaction between PAH and Hydrophobic Salt. As the aging time increased, PAH formed self assemblies with potassium hydrogen phthalate.…”

Nanopatterned Surfaces for Biomedical Applications

“…A relatively simple method to generate micro-and nanotopographies with a certain degree of control is by phase separation of polymers. This can either be polymer blends (Affrossman, Henn et al 1996;Affrossman, Jerome et al 2000) or block copolymers (Olayo-Valles, Lund et al 2004;Krishnamoorthy, Pugin et al 2006). Here the polymers are dissolved in a common solvent and spin coated on relevant substrates (often glass).…”

Combining Micelle Self‐Assembly with Nanostencil Lithography to Create Periodic/Aperiodic Micro‐/Nanopatterns on Surfaces

“…[15][16][17][18][19] Realizing nanodevices or technology-platforms based on nanostructures often demands excellent control over the dimensions, spacing, surface coverage and also surface placement of nanostructures. In our earlier work, we had demonstrated the tunability of characteristic dimensions of 2D arrays of copolymer micelles [20] and that of nanopillars on diverse substrates (Si, Si 3 N 4 , SiO 2 , and Quartz) derived from use of copolymer micelles as dry etch masks. [21] In this report, we present a smart exploitation of nanostencil lithography, a high-throughput top-down tool, to define the surface placement of copolymer derived surface nanostructures.…”