title: Polymer ligand-induced autonomous sorting and reversible phase separation in binary particle blends.
abstract: The tethering of ligands to nanoparticles has emerged as an important strategy to control interactions and organization in particle assembly structures. We demonstrate that ligand interactions in mixtures of polymer-tethered nanoparticles (which are modified with distinct types of polymer chains) can impart upper or lower critical solution temperature (UCST/LCST)-type phase behavior on binary particle mixtures in analogy to the phase behavior of the corresponding linear polymer blends. Therefore, cooling (or heating) of polymer-tethered particle blends with appropriate architecture to temperatures below (or above) the UCST (or LCST) results in the organization of the individual particle constituents into monotype microdomain structures. The shape (bicontinuous or island-type) and lengthscale of particle microdomains can be tuned by variation of the composition and thermal process conditions. Thermal cycling of LCST particle brush blends through the critical temperature enables the reversible growth and dissolution of monoparticle domain structures. The ability to autonomously and reversibly organize multicomponent particle mixtures into monotype microdomain structures could enable transformative advances in the high-throughput fabrication of solid films with tailored and mutable structures and properties that play an important role in a range of nanoparticle-based material technologies.
authors.affiliation: Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA.
authors.forename: Michael
authors.identifier: 0000-0002-5762-6296
authors.initials: M
authors.lastname: Schmitt
authors.affiliation: Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA.; Chemistry Department, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, USA.
authors.forename: Jianan
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA.
authors.forename: Jaejun
authors.initials: J
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA.
authors.forename: Bongjoon
authors.identifier: 0000-0001-6318-2014
authors.initials: B
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA.
authors.forename: Xin
authors.initials: X
authors.lastname: Ning
authors.affiliation: Department of Polymer Engineering, Polymer Engineering Academic Center, University of Akron, 250 South Forge Street, Akron, OH 44325-0301, USA.
authors.forename: Ren
authors.identifier: 0000-0002-9836-689X
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Department of Polymer Engineering, Polymer Engineering Academic Center, University of Akron, 250 South Forge Street, Akron, OH 44325-0301, USA.
authors.forename: Alamgir
authors.identifier: 0000-0003-1302-9374
authors.initials: A
authors.lastname: Karim
authors.affiliation: Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA.
authors.forename: Robert F
authors.identifier: 0000-0002-4437-0885
authors.initials: RF
authors.lastname: Davis
authors.affiliation: Chemistry Department, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, USA.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Matyjaszewski
authors.affiliation: Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Bockstaller
keywords: ATRP; Nanocomposite; Polymer; Self-assembly; brush; colloid; controlled radical polymerization; nanoparticle; phase separation; surface