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.
Bibliographical noteFunding Information:
M.R.B., R.F.D., K.M., and A.K. acknowledge financial support by the NSF (via DMR-1410845, DMR-1501324, and DMR-1411046) and the Department of Energy (via DE-EE0006702). M.S. further acknowledges financial support from the John and Clare Bertucci Graduate Fellowship. J.Z. acknowledges scholarship support by the China Scholarship Council and by the Scott Institute for Energy Innovation at Carnegie Mellon University. The authors further acknowledge use of the Materials Characterization Facility at Carnegie Mellon University supported by grant MCF-677785. Author contributions: M.S., J.L., and X.N.
© 2016 The Authors.