Bharath Natarajan

• PhD, Materials Science and Engineering. B.Tech, Mechanical Engineering.
• Member of Technical Staff at ExxonMobil

Carbon nanotube (CNT) reinforced polymers are next-generation, high-performance, multifunctional materials with a wide array of promising applications. The successful introduction of such materials is hampered by the lack of a quantitative understanding of process-structure-property relationships. These relationships can be developed only through t...

Developing structure–property relationships between the filler/matrix interface chemistry and the dispersion and interface properties of polymer nanocomposites (PNC) is critical to predicting their bulk mechanical, electrical, and optical properties. In this paper we develop quantitative relationships between interfacial surface energy parameters a...

RAFT (reversible addition–fragmentation chain transfer) polymerization has been widely used to synthesize different polymer architectures such as polymer brushes on nanoparticles for incorporation into polymer nanocomposites. It is believed that these polymer brushes, with the same chemistry as the matrix polymer, can be employed to improve filler...

Accelerated insertion of nanocomposites into advanced applications is predicated on the ability to perform a priori property predictions on the resulting materials. In this paper, a paradigm for the virtual design of spherical nanoparticle‐filled polymers is demonstrated. A key component of this “Materials Genomics” approach is the development and...

While recent efforts have shown how local structure plays an essential role in the dynamic heterogeneity of homogeneous glass-forming materials, systems containing interfaces such as thin films or composite materials remain poorly understood. It is known that interfaces perturb the molecular packing nearby, however, numerous studies show the dynami...

While recent efforts have shown how local structure plays an essential role in the dynamic heterogeneity of homogeneous glass-forming materials, systems containing interfaces such as thin films or composite materials remain poorly understood. It is known that interfaces perturb the molecular packing nearby, however, numerous studies show the dynami...

Economical CO2 capture demands low-energy separation strategies. We use a liquid-infused surface (LIS) approach to immobilize reactive liquids, such as amines, on a textured and thermally conductive solid substrate with high surface-area to volume ratio (A/V) continuum geometry. The infused, micrometer-thick liquid retains that high A/V and directl...

The ability to predict liquid transport rates on textured surfaces is key to the design and optimization of devices and processes such as oil recovery, coatings, reaction-separation, high-throughput screening, and thermal management. In this work we develop a fully analytical model to predict the propagation coefficients for liquids hemiwicking thr...

The use of nanoparticle reinforced polymer matrices in continuous fiber composites for infrastructure applications requires a comprehensive understanding of viscoelastic creep. Critical parameters affecting the mechanical reinforcement offered by nanoparticles include nanoparticle size and concentration, as well as the interaction between the nanop...

In all prior electromagnetic modeling studies of carbon nanotube (CNT) composites, the exact three-dimensional (3D) shape and spatial distribution of the CNTs in the composite were unknown. Therefore, simplifying assumptions had to be made regarding the CNT distributions. The effect of such assumptions on the electromagnetic response of CNT composi...

Carbon nanostructure (CNS) based polymer nanocomposites (PNCs) are of interest due to the superior properties of the CNS themselves, scale effects, and the ability to transfer these properties anisotropically to...

Carbon-nanotube (CNT) grafted glass-fiber-reinforced epoxy nanocomposites (GFRP) present a range of stiffnesses (MPa to GPa) and length scales (µm to nm) at the fiber-matrix interface. The contribution of functionalized CNT networks to the local and bulk polymer dynamics is studied here using a combination of torsion dynamical mechanical thermal an...

Graphitic carbon has attracted tremendous research interest in recent years owing to its exceptional thermal and electrical properties that arise from the ordered sp² hybridized carbon structure. Due to its high activation energy, graphitization is often energy- and chemical-intensive. In addition, the electrical conductivity of graphitized materia...

The development of biocompatible polymer nano-composites that enhance mechanical properties while maintaining thermoplastic processability is a longstanding goal in sustainable materials. When the matrix is semi-crystalline, the nanoparticles may induce significant changes to crystallization kinetics and morphology due to their ability to act as nu...

Metal organic framework materials (MOFs) have been primarily recognized for their ability to promote selective storage of gas molecules. In their as-synthesized (powdered) form, MOFs are not easily processed for use in end-devices where their properties might be exploited. Composites have been produced in which either zeolite imidazolate framework-...

The interaction between the metal nanoparticles and their substrate plays a critical role in determining the particle morphology, distribution, and properties. Here we present the pronounced impact of a thin oxide coating to the dispersion of metal nanoparticles on a carbon matrix. We employ Al2O3-supported Pt nanoparticles in comparison with direc...

The twisted plywood, or Bouligand, structure is the most commonly observed microstructural motif in natural materials that possess high mechanical strength and toughness, such as that found in bone and the mantis shrimp dactyl club. These materials are isotropically toughened by a low volume fraction of soft, energy-dissipating polymer and by the B...

For many reaction processes, such as catalysis, phase transformations, nanomaterial synthesis etc., nanoscale observations at high spatial (sub-nanometer) and temporal (millisecond) resolution are required to characterize and comprehend the underlying factors that favor one reaction over another. The combination of such spatial and temporal resolut...

The push to advance efficient, renewable, and clean energy sources has brought with it an effort to generate materials that are capable of storing hydrogen. Metal–organic framework materials (MOFs) have been the focus of many such studies as they are categorized for their large internal surface areas. We have addressed one of the major shortcomings...

The effect of large deformation on the chain dynamics in attractive polymer nanocomposites was investigated using neutron scattering techniques. Quasielastic neutron backscattering measurements reveal a substantial reduction of polymer mobility in the presence of attractive, well-dispersed nanoparticles. Additionally, large deformations are observe...

During the catalytic synthesis of graphene, nanotubes, fibers, and other nanostructures, many intriguing phenomena occur, such as phase separation, precipitation, and analogs of capillary action. We demonstrate that catalytic nanoparticles display metastable states that influence growth, reminiscent of some protein ensembles in vivo. As a carbon na...

During the catalytic synthesis of graphene, nanotubes, fibers, and other nanostructures, many intriguing phenomena occur, such as phase separation, precipitation, and analogs of capillary action. We demonstrate that catalytic nanoparticles display metastable states that influence growth, reminiscent of some protein ensembles in vivo. As a carbon na...

The utility of gold nanorods for plasmonic applications largely depends on the relative orientation and proximity of the nanorods. Though side-by-side or chain-like nanorod morphologies have been previously demonstrated, a simple reliable method to obtain high-yield oriented gold nanorod assemblies remains a significant challenge. We present a faci...

Measuring the Phase Transformation Kinetics Under Non-Equilibrium Conditions from Time Resolved High Resolution TEM Images - Volume 23 Issue S1 - Renu Sharma, Zahra Hussani, Pin Ann Lin, Bharath Natarajan

A known deterrent to the large-scale development and use of cellulose nanocrystals (CNCs) in composite materials is their affinity for moisture, which has a profound effect on dispersion, wetting, interfacial adhesion, matrix crystallization, water uptake and hydrothermal stability. To quantify and control the hydration and confinement of absorbed...

Rational catalyst design requires an atomic scale mechanistic understanding of the chemical pathways involved in the catalytic process. A heterogeneous catalyst typically works by adsorbing reactants onto its surface, where the energies for specific bonds to dissociate and/or combine with other species (to form desired intermediate or final product...

Using neutron spin-echo spectroscopy, X-ray photon correlation spectroscopy and bulk rheology, we studied the effect of particle size on the single chain dynamics, particle mobility, and bulk viscosity in athermal polyethylene oxide-gold nanoparticle composites. The results reveal an ≈ 25 % increase in the reptation tube diameter with addition of n...

Cellulose is the most abundant renewable material in nature. In this work, ordered cellulose nanocrystals (CNCs) have been transformed into porous carbon with an increased short-range ordered lattice and percolated carbon nanofiber at a relatively low carbonization temperature of 1000 °C. When evaluated as anode for sodium-ion batteries (SIBs), the...

Polymer nanocomposites consist of at least two phases: a polymeric matrix phase and an inorganic nanofiller phase. To enhance the overall performance of polymer nanocomposites, efforts have been made to improve the intrinsic properties of both the matrix and the nanofiller. A hidden lever for performance optimization, however, lies in understanding...

Carbon nanotube composites are lightweight, multifunctional materials with readily adjustable me-chanical and electrical properties-relevant to the aerospace,[1] automotive,[2] and sporting goods[3] indus-tries as high-performance structural materials.[4,5] Here, we combine well-established and newly-developed characterization techniques[6,7] to de...

Carbon nanotube (CNT) polymer nanocomposites are attractive multifunctional materials with a growing range of commercial applications. With the increasing demand for these materials, it is imperative to develop and validate methods for on-line quality control and process monitoring during production. In this work, a novel combination of characteriz...

Carbon nanotube (CNT) nanocomposites are enticing materials that enable engineers to tailor structural and electrical properties for applications in the automotive and aerospace industries. CNT mass fraction and the matrix cure temperature are two ways to tune the direct and alternating current electrical properties of these nanocomposites; yet, ho...

div class="title">Automated Image Processing Scheme to Measure Atomic-Scale Structural Fluctuations - Volume 22 Issue S3 - Zahra Hussaini, Pin Ann Lin, Wenhui Zhu, Bharath Natarajan, Renu Sharma

Carbon nanotube (CNT) sheets represent a novel implementation of CNTs that enable the tailoring of electrical and mechanical properties for applications in the automotive and aerospace industries. Small molecule functionalization and postprocessing techniques, such as irradiation with high-energy particles, are methods that can enhance the mechanic...

Prevention of microbially induced corrosion (MIC) is of great significance in many environmental applications. Here, we report the use of an ultra-thin, graphene skin (Gr) as a superior anti-MIC coating over two commercial polymeric coatings, Parylene-C (PA) and Polyurethane (PU). We find that Nickel (Ni) dissolution in a corrosion cell with Gr-coa...

Superconductivity results from a Bose condensate of Cooper-paired electrons with a macroscopic quantum wave function. Dramatic effects can occur when the region of the condensate is shaped and confined to the nanometer scale. Recent progress in nanostructured superconductors has revealed a route to topological superconductivity, with possible appli...

Electromagnetic scattering from Carbon Nanotubes (CNT) has received wide interest in the past decade. Many different CNT configurations have been computationally investigated such as single CNTs, infinite planar arrays of CNTs, finite arrays with simple distributions, and bundles of CNTs. In all of the previously reported configurations, the CNTs w...

Maximum performance enhancement in polymer nanocomposites is predicated on the simultaneous realization of maximum filler loading, controlled filler dispersion and structural integrity. Through the example of high refractive index ZrO2/polydimethylsiloxane encapsulants for LEDs for enhanced light extraction efficiency, this paper demonstrates that...

The Materials Genome Initiative (MGI) was conceived as a unified effort to capture, curate, and exploit materials structure/property information on a grand scale to enable rapid, cost-effective development of novel materials with predictable properties. While the use of "genomic" methods to facilitate property prediction, virtual design, and discov...

The enthalpic incompatibility of organic polymer matrices and high surface energy inorganic nanoparticles often leads to phase separation in polymer nanocomposites (PNC) precluding the realization of anticipated property enhancements. The grafting of polymer chains to nanoparticles holds promise as a means for controlling dispersion. A single popul...

Polymer nanocomposites (PNC) are complex material systems in which the dominant length scales converge. Our approach to understanding nanocomposite tradespace uses Materials Quantitative Structure-Property Relationships (MQSPRs) to relate molecular structures to the polar and dispersive components of corresponding surface tensions. If the polar and...

Polymer Nanocomposites (PNC) are a fascinating category of material systems, in which nanoscopic fillers are found to induce remarkable improvements in the properties of the polymeric matrix.[1] This improvement is often determined by the interfacial energetic interactions which dictate the matrix chain mobility, filler dispersion, and distribution...