Interface-Mediated Assembly Of Tunable Anisotropic Nanoparticle Clusters And Phases
July 21-24, 2019
This talk will introduce a new approach for assembling spherical nanoparticles into anisotropic architectures within a polymer matrix . The approach takes advantage of differences in the surface tension between two immiscible polymers forming a bilayer, and those between polymer grafts attached on the particles and the two polymer layers, to trap nanoparticles within 2D planes at tunable distances parallel to the interface. The interactions between multiple nanoparticles trapped in distinct planes can then be used to assemble particles into unique arrangements near the interface. We carry out molecular dynamics simulations of coarse-grained models of polymer-grafted nanoparticles in a polymer bilayer to demonstrate the viability of the proposed strategy. We demonstrate the assembly of nanoparticles clusters, such as dimers with tunable tilt relative to the interface and trimers with tunable bending angles. We also show how these nanoparticle motifs can be further assembled into quasi-1D phases, such as linear serpentine chains and branched structures, as well as 2D macroscopic phases, such as ridged hexagonal monolayers and square-ordered bilayers. We develop an analytical model to predict the positions and free energies of trapped nanoparticles that shows excellent agreement with simulation results. Lastly, we demonstrate that our approach could also be used for controlling the orientation and assembly of anisotropic nanoparticles at the interface.
 T-Y Tang, Y Zhou, and G Arya, “Interfacial Assembly of Tunable Anisotropic Nanoparticle Architectures,” ACS Nano 13, 2019: 4111-4123
Guarav Arya, Tsung-Yeh Tang, and Yilong Zhou, "Interface-Mediated Assembly Of Tunable Anisotropic Nanoparticle Clusters And Phases" in "Colloidal, Macromolecular and Biological Gels II", Samiul Amin, Manhattan College, USA Saad Khan, North Carolina State University, USA Srini Raghavan, University of Maryland College Park, USA Eds, ECI Symposium Series, (2019). https://dc.engconfintl.org/cmb_gels_ii/9