Friction-directed self-assembly of Janus lithographic microgels into anisotropic 2D structures

Kodakkadan, Yadu Nath Vakkipurath and Maslen, Charlie and Cigler, Petr and Štěpánek, František and Rehor, Ivan (2021) Friction-directed self-assembly of Janus lithographic microgels into anisotropic 2D structures. Journal of Materials Chemistry B, 9 (23). pp. 4718-4725. ISSN 2050-750X (https://doi.org/10.1039/D1TB00572C)

[thumbnail of Kodakkadan-etal-JMCB-2021-Friction-directed-self-assembly-of-Janus-lithographic-microgels]
Preview
 Text. Filename: Kodakkadan-etal-JMCB-2021-Friction-directed-self-assembly-of-Janus-lithographic-microgels.pdf
Accepted Author Manuscript
License: Strathprints license 1.0
Download (1MB)| Preview

Abstract

We present a method for creating ordered 2D structures with material anisotropy from self-assembling micro-sized hydrogel particles (microgels). Microgel platelets of polygonal shapes (hexagon, square, and rhombus), obtained by a continuous scalable lithographic process, are suspended in an aqueous environment and sediment on an inclined plane. As a consequence of gravitational pull, they slide over the plane. Each half of the microgel is composed of a different type of hydrogel [poly(N-isopropylacrylamide) (PNIPAM), and poly(ethylene glycol) diacrylate (PEGDA), respectively] which exhibit different frictional coefficients when sheared over a substrate. Hence the microgels self-orientate as they slide, and the side with the lower frictional coefficient positions in the direction of sliding. The self-oriented microgels concentrate at the bottom of the tilted plane. Here they form densely packed structures with translational as well as orientational order.

ORCID iDs

Kodakkadan, Yadu Nath Vakkipurath, Maslen, Charlie ORCID logoORCID: https://orcid.org/0000-0003-2995-0918, Cigler, Petr, Štěpánek, František and Rehor, Ivan;
CORE (COnnecting REpositories)