Schadler Group Research

The focus in my research group is tailoring of the interface between nanoscale fillers, and a matrix material (be that a polymer or a biomolecule) in order to control macroscopic properties.

We currently have projects in the Materials Genome, Nanodielectrics, Functional optical nanocomposites, tailoring biological function with nanoparticles, and understanding the fundamental behavior of interfaces in polymer nanocomposites.

My philosophy on advising is to have a small enough group that I have time to meet with each project for at least 30 min every week, and to allow the students to take ownership of the project as soon as they are able. We also have a weekly group meeting during which one or two students present their latest results and critically review a recent paper.

Examples of our past contributions include:

Most Recent Field - Materials Genome

This early work demonstrated, we believe for the first time, the use of heuristics models, specifically MQSPR to bridge length scales from the atomistic to the continuum level. Later work is expanding into database development and tools.

"Dielectric Spectroscopy Analysis using Viscoelasticity-inspired Relaxation Theory with Finite Element Modeling," He Zhao, Yang Li, Yanhui Huang, Tim Krentz, Michael Bell, Brian Benicewicz, Linda S. Schadler, L. Catherine Brinson, Computer Methods in Applied Mechanics and Engineering, submitted, 2015

"Towards the Development of a Quantitative Tool for Predicting Dispersion of Nanocomposites Under Non-Equilibrium Processing Conditions," I. Hassinger, X. Li, H. Zhao, H. Xu, Y. Huang, A. Prasad, L. S. Schadler, W. Chen, L.C. Brinson, Journal of Materials Science, 2015 (in press).

"Microstructure Reconstruction and Structural Equation Modeling for Computational Design of Nanodielectrics," Y. Zhang, H. Zhao, I. Hassinger, L.C. Brinson, L.S. Schadler, W. Chen, Integrating Materials and Manufacturing Innovation, 2015, (published online and in press).

"Stalking the Materials Genome: A Data-Driven Approach to the Virtual Design of Nanostructured Polymers," C. M. Breneman, L.C. Brinson, L.S. Schadler, B. Natarajan, M. Krein, K. Wu, L. Morkowchuk, Y. Li, H. Deng, D. Gai, Advanced Functional Materials, vol. 10, no. 6, 1-7 (2013).

"The Effect of Interfacial Energetics on Dispersion and Glass Transition Temperature in Polymer Nanocomposites," B. Natarajan, Y. Li, H. Deng, C. Brinson, L. S. Schadler, Macromolecules, vol. 36, no. 7, 2833-2841 (2013).

Recent Papers in Nanodielectrics

This work has focused on understanding how to control the dielectric properties of nanofilled polymers including the non-linear field grading response, and the insulating properties. Much of this work has been funded by ABB Corporation or EPRI and has resulted in several scale up projects. At the same time, we have been able to gain significant insight into the mechanisms underlying the improvement in dielectric breakdown strength and endurance strength.

"Dielectric Breakdown Strength of Epoxy Bimodal-Polymer-Brush-Grafted Core Functionalized Silica Nanocomposites," S. Virtanen, T. Krentz, J.K. Nelson, L.S. Schadler, M. Bell, B.C. Benicewicz, H. Hillborg, S. Zhao, IEEE Transactions on Dielectrics and Electrical Insulation, vol. 21, no. 2, 563-570 (2014).

"Dielectric Constant and Breakdown Strength of Polymer Composites with High Aspect Ratio Fillers Studied by Finite Element Models," Z. Wang, J.K. Nelson, S. Zhao, H. Hillborg, L.S. Schadler, Composites Science and Technology, vol. 76, 29-36 (2013).

"The Influence of Moisture on the Electrical Properties of Crosslinked Polyethylene/Silica Nanocomposites," L.Hui, L.S. Schadler, J.K. Nelson, IEEE Transactions on Dielectrics and Electrical Insulation, vol. 20, no.2, 641-653 (2013).

"High Temperature Breakdown Strength and Voltage Endurance Characterization of Nanofilled Polyamideimide," L.S. Schadler, J.K. Nelson, C. Calebrese, A. Travelpiece, D. Schweikart, IEEE Transactions on Dielectrics and Electrical Insulation, vol. 19, no. 6, 2090-2101 (2012).

"Graphene Oxide Filled Nanocomposite with Novel Electrical and Dielectric Properties," Zepu Wang, J. Keith Nelson, Henrik Hillborg, Su, Zhao, Linda.S. Schadler, Advanced Materials, vol. 24, no. 23, 3134-3137 (2012).

"Effect of High Aspect Ratio Filler on Dielectric Properties of Polymer Composites: A Study on Barium Titanate Fibers and Graphene Platelets," Zepu Wang, J. Keith Nelson, Jianjun Miao, Robert J. Linhardt, Linda S. Schadler, Henrik Hillborg, Su Zhao, IEEE Transactions on Dielectrics and Electrical Insulation, vol. 19, no. 3, 960-967 (2012).

Papers in Grafted Polymer Nanoparticle Composites

This fundamental work has focused on understanding how to control the dispersion and properties of the interfacial region in spherical nanoparticle filled polymer composites through control of the enthalpic and entropic interface energy. The predictive ability gained is leading to excellent control over morphology for applications in lighting and nanodielectrics

"Effect of graft density and molecular weight on mechanical properties of rubbery block copolymer grafted SiO2 nanoparticle toughened epoxy," J. Gao, J. Li, S. Zhao, B. Benicewicz, H. Hillborg, and L. S. Schadler, Polymer, vol. 54, no.15, 3961-3973 (2013).

"Transparent Luminescent Silicone Nanocomposites Filled with Bimodal PDMS-Brush-Grafted CdSe Quantum Dots," Peng Tao, R.W. Siegel, L.S. Schadler, J. Materials Chemistry C. vol. 1, no. 1, 86-94 (2013).

"Bulk Transparent TiO2/Epoxy Nanocomposites Filled with Poly(glycidyl methacrylate) Brush-Grafted Nanoparticles," P. Tao, A. Viswannath, Y. Li, R. W Siegel, B. C Benicewicz, L. S Schadler, Polymer, vol. 54, no. 6, 1639-1646 (2013).

"Biomodal Surface Ligand Engineering: The Key to Tunable Nanocomposites," Y. Li, P. Tao, A. Viswanath, B.C. Benicewicz, L.S. Schadler, Langmuir (Cover), vol. 29, no. 4, 1211-1220 (2013).

"The Mechanical Properties of Epoxy Composites Filled with Rubbery Copolymer Grafted SiO2," Jianing Gao , Junting Li, Brian C. Benicewicz , Su Zhao , Henrik Hillborg, and Linda S. Schadler, Polymers, vol. 4, no. 1, 187-210 (2012).

"TiO2 nanocomposites with high refractive index and transparency," Peng Tao, Yu Li, Atri Rungta, Anand Viswanath, Jianing Gao, Brian C. Benicewicz, Richard W. Siegel, and Linda S. Schadler, J. Mater. Chem., vol. 21, no. 46, 18623 - 18629 (2011).

"Preparation and Optical Properties of Indium Tin Oxide/Epoxy Nanocomposites with Polyglycidyl Methacrylate Grafted Nanoparticles," Peng Tao, Anand Viswanath, Linda S. Schadler, Brian C. Benicewicz, and Richard W. Siegel, ACS Applied Materials and Interfaces, vol. 28, no. 39, 3638-3645 (2011).

"Gel-like" Mechanical Reinforcement in Polymer Nanocomposites," Pinar Akcora, Sanat K. Kumar* , Sarah Lewis, Linda S. Schadler, Yu Li, Brian C. Benicewicz, Alec Sandy, Suresh Narayanan, Pappannan Thiyagarajan, Ralph H. Colby, Jack F. Douglas, Macromolecules, vol 43, 1011-1015 (2010).

"Conformational Transitions of Spherical Polymer Brushes: Synthesis, Characterization, and Theory," Douglas Dukes, Yu Li, Sarah Lewis, Brian Benicewicz, Linda Schadler, Michael Tambasco, Sanat Kumar, Macromolecules, vol. 43, 1564-1570 (2010).

"Anisotropic Self-Assembly of Spherical Polymer-Grafted Nanoparticles," Pinar Akcora, Hongjun Liu, Sanat K. Kumar, Yu Li, Brian C. Benicewicz, Linda S. Schadler, Devrim Acehan, Athanassios Z. Panagiotopoulos, Jack F. Douglas, Nature Materials, vol. 8, no. 4, 354-U121 (2009).

Papers in Nanotube Composites

Our work in this field provided insight into the micro/nanomechanical behavior of nanotube filled polymers and we also did some of the early work on nanotube surface modification to control properties.

"Polymer Nanocomposite Foams," L. Chen, D. Rende, R. Ozisik, L.S. Schadler, Invited Paper for J. Materials Chemistry A: Featured Articles, vol. 1, no. 12, 3837-3850 (2013).

"Controlling Bubble Density in MWNT/Polymer Nanocomposite Foams by MWNT Surface Modification," L. Chen, R. B.K. Goren, R. Ozisik, L.S. Schadler, Composites Science and Technology, vol. 72, no. 2, 190-196 (2012).

"An Experimental and Theoretical Investigation of the Compressive Properties of Multi-walled Carbon Nanotube/Poly(methyl methacrylate) Nanocomposite Foams," L. Chen, B.K. Goren, R. Ozisik, L.S. Schadler, Polymer, vol. 52, no. 13, 2899-2909 (2011).

"The influence of carbon nanotube aspect ratio on the foam morphology of MWNT/PMMA nanocomposite foams," Limeng Chen, Rahmi Ozisik, Linda S. Schadler, Polymer, vol. 51, 2368-2375 (2010).

"Viscoelastic behavior of nanotube-filled polycarbonate: effect of aspect ratio and interface chemistry," Renée K. Duncan, R. Qiao, J.B. Bult, D. Burris, L.C. Brinson and L.S. Schadler, International Journal of Smart and Nano Materials, vol.1, no. 1, 53-68 (2010).

"Measurement of the Critical Aspect Ratio and Interfacial Shear Strength in MWNT/Polymer Composites," R.K. Duncan, X.G. Chen, J.B. Bult, L.C. Brinson, L.S. Schadler, Composites Science and Technology, vol. 70, no. 4, 599-605 (2010).

Papers in Short Molecule Modified Polymer Nanocomposites

These papers are a mix of many different projects exploring the impact of nanofillers on properties ranging from glass transition temperature to tribology to mechanical properties.

"Supercritical carbon dioxide assisted dispersion and distribution of silica nanoparticles in polymers," Kerem Goren, Osman B. Okan, Limeng Chen, Linda S. Schadler, Rahmi Ozisik, Journal of Supercritical Fluids, vol. 67, 108-113, (2012).

"Improvements and Mechanisms of Fracture and Fatigue Properties of Well-Dispersed Alumina/Epoxy Nanocomposites," Su Zhao, Linda S. Schadler, Henrik Hillborg, Tommaso Auletta, Composite Science and Technology, vol. 68, no. 14, 2965-2975 (2008).

"Mechanisms Leading to Improved Mechanical Performance in Nanoscale Alumina Filled Epoxy," Su Zhao, Linda S. Schadler, Henrik Hillborg, Tommaso Auletta, Composite Science and Technology, vol. 68, no. 14, 2976-2982 (2008).

"Tribological Investigation of the Effects of Particle Size, Loading and Crystallinity on Poly(Ethylene) Terephthalate Nanocomposites," Praveen Bhimaraj, David Burris, W. Gregory Sawyer, C. Gregory Toney, Richard W. Siegel, Linda S. Schadler, Wear, vol. 264, 632-637 (2008).