Fabrication of Micropatterned Self‐Oscillating Polymer Brush for Direction Control of Chemical Waves

• Published in: Small (Weinheim an der Bergstrasse, Germany) Vol. 13; no. 21
• Main Authors: Homma, Kenta, Masuda, Tsukuru, Akimoto, Aya Mizutani, Nagase, Kenichi, Itoga, Kazuyoshi, Okano, Teruo, Yoshida, Ryo
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.06.2017
• Subjects: Brushes; Catalysts; chemical waves; Fluorescence; Fourier analysis; Fourier transforms; Infrared lasers; Infrared spectroscopy; Isopropylacrylamide; Laser microscopy; Microscopy; Nanotechnology; oscillating chemical reaction; Photoelectron spectroscopy; Photolithography; polymer brushes; Polymerization; Polymers; Propagation (polymerization); Spectroscopic analysis; Spectrum analysis; surface‐initiated atom transfer radical polymerization; Wave propagation; photolithography; chemical waves; surface-initiated atom transfer radical polymerization; polymer brushes; oscillating chemical reaction
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.201700041

The propagation control of chemical waves via a pentagonal patterned structure in a self‐oscillating polymer brush composed of N‐isopropylacrylamide and a metal catalyst for the Belousov–Zhabotinsky (BZ) reaction is reported. The patterned self‐oscillating polymer brush is prepared by combining surface‐initiated atom transfer radical polymerization and maskless photolithography. Surface modification is confirmed by X‐ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, 3D measuring laser microscopy, and fluorescence microscopy. The polymer brush patterns are fabricated with gaps between the pentagonal regions, and investigations on the effect of the gap distance on the BZ reaction reveal that at the appropriate distance, chemical waves propagate across the array from the plane to the corner between the patterns. Unidirectional control is achieved not only in the 1D array, but also in a 2D curved array. This patterned self‐oscillating polymer brush is a novel and advantageous approach for creating an autonomous dynamic soft interface. Pentagonal patterned polymer brushes are fabricated to control spatiotemporal function on the surface. The polymer brush is prepared by surface modification of a self‐oscillating polymer that exhibits autonomous conformation changes. The microlevel precision in patterning of the polymer brush via maskless photolithography allows the chemical waves to travel in one direction along the pentagonal array of this self‐oscillating surface.