Polymer-inorganic nanocomposites – materials in which inorganic nanoscale inclusions (“fillers”) are added to a polymer host (“matrix”) – are of great interest for many industrial applications. The physical and mechanical properties of nanocomposites depend crucially on our ability to design and control their morphology, i.e., the arrangement of the particles in the matrix. The nanocomposite morphologies depend on a number of factors, such as the size and shape of the fillers, the molecular weight and composition of the matrix polymer, and the interactions between the filler and the matrix. In most cases, the interaction between the matrix and the filler is very unfavorable, leading to aggregation of the filler particles and poor mechanical or physical properties. To counter this effect, in recent years, filler particles are being functionalized by oligomeric ligands covalently bonded to particle surfaces. These “hairy” nanoparticles can organize into complex soft-crystalline 3d, 2d, or 1d structures. We develop a mesoscale field theory (combination of Self-Consistent Field Theory for polymers and Density Functional Theory for particles) to describe the nanocomposite morphologies. Two specific examples are considered. In the first case, we investigate the arrangements of organically modified (“hairy”) spherical nanoparticles dispersed in a polymer matrix. Depending on the particle volume fraction, ligand grafting density, and ligand/matrix polymer molecular weight ratio, we find structures such as 3d-aggregates, 2d-sheets, and 1d-strings. Those results are in a good qualitative agreement with earlier experiments (P. Akcora et al., Nature Materials 2009) and simulations. The second example is the case of single-component nanocomposites (“hairy” nanoparticles with no matrix). Here, again, we find various structures, from 3d FCC crystals to 2d sheets to 1d lamellae. These predictions are also in good qualitative agreement with experimental results and particle-based simulations of Glotzer and co-workers (R. Marson et al., MRS Communications 2015). These findings demonstrate that field-based mesoscale simulations are going to play important role in designing new polymeric and polymer-based nanocomposite materials.

I received my B.S. (Physics) and Ph. D. (Polymer Physics) from Moscow Institute of Physics and Technology (“FizTech”), Moscow, Russia, with Ph.D. thesis on “Modeling the Dynamics and Thermodynamics of Melting Polyethylene Crystals” (advisor Prof. Leonid I. Manevitch). After moving to the US in 1992, I worked as a postdoctoral researcher at the University of Colorado (1993-97, advisor Prof. Noel A. Clark) and the University of Pittsburgh (1998-2000, advisor Prof. Anna C. Balazs). In early 2001, I joined Corporate R&D of The Dow Chemical Company in Midland, Michigan, where I am currently a Senior Research Scientist. My research interests are in applied theoretical and computational polymer science, with specific emphasis on polymer-inorganic nanocomposites, polyurethane foams and elastomers, directed self-assembly of block copolymers, and other applications of polymer theory to predict structure-property relationships in industrially relevant systems. I am a Fellow of American Physical Society (2014), and recipient of Dow internal award for Excellence in Science (2015).