Research

Research Overview

My research integrates polymer physics, dielectric physics, and polymer nanocomposite science blended with an engineering approach to advance energy materials for next-generation electronics and storage technologies. Using various techniques like broadband dielectric spectroscopy, as well as, dynamic mechanical analysis, rheology, and calorimetry, and combined with rigorous data analysis and fitting approaches, I establish relationships between molecular characteristics, relaxation and charge transport dynamics, and performance. This enables rational design of materials with tailored electrical, thermal and mechanical properties. By optimizing processing and structure–property relationships, my work advances scientific understanding and technological innovation to address global energy challenges.

Representitives Research Articles

Polyacrylate Vitrimer Network via In Situ Isocyanide Copolymerization: Synthesis and Molecular Dynamics
Journal of the American Chemical Society (2026)

Widespread plastic pollution highlights the urgent need for materials with sustainable end-of-life management. Vitrimers, cross-linked polymers containing dynamic covalent bonds, combine the durability of thermosets with their recyclability. Here, we report a one-step photocopolymerization using multifunctional isocyanides as readily accessible cross-linkers that directly introduce vinylogous urethane-like linkages into polyacrylate networks, structures difficult to obtain via amine–β-ketoester condensation. The resulting materials show good reprocessability, maintaining a comparable mechanical performance after three processing cycles. Broadband dielectric spectroscopy (BDS) reveals that the temperature dependence of the bond-exchange relaxation times evolves from a kink-like response in fresh samples to Arrhenius behavior after annealing, visualizing topological rearrangement and defect healing. A scaling relationship between bond-exchange relaxation and electrical conductivity establishes that the former is the underlying mechanism for charge transport in vitrimers. Furthermore, dipolar intermediates generated during bond exchange increase the dielectric permittivity, providing new insight into designing sustainable dielectric materials. Read more

Universal Scaling of DC Conductivity with Dielectric Interfacial Polarization in Conjugated Polymers
Macromolecules (2024)

Understanding the intricate relationship between conductivity and polymer film microstructure is paramount to designing and developing high-performance conjugated-polymer-based electronic devices. Conjugated polymers are typically semicrystalline, and their films comprise both highly crystalline and amorphous regions with significant disparity between the conductivity of these regions. However, traditional conductivity measurements under steady-state conditions overlook the presence of the amorphous phase, offering an incomplete perspective on charge transport. Here, by employing isothermal dielectric measurements, we reveal that the amorphous phase plays a pivotal role and dominates the electrical conductivity at temperatures more pertinent to practical applications, while the crystalline fraction takes precedence at temperatures below room temperature. The conductivity mismatch between the amorphous and crystalline phases yields the Maxwell-Wagner-Sillars interfacial polarization (MWS-IP) effect. Here we demonstrated that the existence of MWS-IP ensues a universal scaling between the electrical conductivity, the relaxation time and the dielectric relaxation strength, for various conjugated polymers and their blends. Shedding light on the contribution of the amorphous phase in the conductivity of conjugated polymers can lead to the development of new polymers for applications in electronic devices with improved performance at operationally relevant temperatures. Read more

Epoxy/clay nanodielectrics: from relaxation dynamics to capacitive energy storage
Advanced Composites & Hybrid Materials (2024)

Nanodielectric systems based on a high glass-to-rubber transition temperature (T_g) epoxy resin modified with laponite® (Na⁺_0.7[(Si₈Mg_5.5Li_0.3)O₂₀(OH)₄]^–0.7) cylindrical nanoparticles were developed and examined as dielectric materials for capacitive energy storage applications. Laponite is an inexpensive synthetic nanoclay that has recently gathered attention as potent electrode material for batteries, due to its high specific surface area and ionic groups. The dielectric properties of the developed nanocomposites were investigated extensively by means of broadband dielectric spectroscopy (BDS), which revealed intense Maxwell–Wagner-Sillars interfacial polarisation (MWS-IP) phenomena at the organic/inorganic interface and an additional dielectric process that showed a strong dependence on the nanoclay concentration, thus attributed to laponite (IDE). It was also found that the presence of laponite significantly altered the temperature dependence of MWS-IP, leading to an enhancement in relaxation times at higher temperatures. The observed phenomenon is attributed to less mobile, adsorbed polymer fragments entrapped between two or more laponite nanoparticles that alters the interphase between the particle and the epoxy. MWS-IP was observed to obey the Barton-Nakajima-Namikawa relation with the dc conductivity values being indicative that both phenomena are associated with the same charge carriers, at different timescales. Moreover, the cycle life performance of epoxy/laponite nanodielectrics was also examined at 30 °C and 120 °C conducting charge/discharge measurements in dc conditions. The addition of laponite nanoparticles endowed the nanodielectric systems with significantly improved capacitive energy efficacy. Read more

Flexible Polymer-Based Nanodielectrics Reinforced with Electrospun Composite Nanofibers for Capacitive Energy Storage
ACS Applied Polymer Materials (2022)

Nanocomposite materials based on polydimethylsiloxane (PDMS) reinforced by electrospun poly(vinylidene fluoride) (PVDF) nanofibers and barium titanate (BTO) nanoparticles were fabricated and tested as dielectric materials for capacitive energy storage applications. Two types of BTO nanoparticles were examined, prior and after ball milling, to investigate the effect of interfacial area and size on the dielectric properties. The morphology of the produced PVDF nanofibers was evaluated via scanning electron microscopy (SEM) to ensure the optimum electrospinning conditions and verify the incorporation of BTO nanoparticles. The composite systems were analyzed by dielectric spectroscopy, and three dielectric processes were revealed: the dynamic glass-to-rubber transition processes of PDMS and PVDF and an interfacial polarization process. It was observed that the dynamic glass-to-rubber transition process of the PVDF nanofibers strongly depends on the size of the BTO nanoparticles that introduce confinement effects and affect thus the temperature dependence of the relaxation. In addition, as verified by ac conductivity, ball milling reduced the conduction of the nanocomposites by 80%, indicating the increase of the charge carrier trapping area around the BTO nanoparticles. Finally, the developed nanocomposites were tested as dielectric materials for capacitor applications at room temperature conducting charge/discharge measurements under the influence of a dc electric field, and their discharge performance and efficiency were examined at various dc voltages (50–300 V) and cycle life. Here, experimental evidence regarding the importance of interfacial area on the energy storage performance in nanodielectrics is presented that will aid the development of more efficient energy materials. Read more

Relaxation Dynamics in Disentangled Ultrahigh Molecular Weight Polyethylene via Torsional Rheology
Industrial & Engineering Chemistry Research (2020)

The relaxation dynamics of disentangled ultrahigh molecular weight polyethylene (UHMWPE) were analyzed by means of torsional rheology in a broad frequency and temperature range. The disentangled specimens were compression-molded at two different temperatures, solid state (125 °C) and melt state (160 °C), and the latter was compared with a melt-state-processed commercial UHMWPE specimen. Three different relaxation processes were observed, namely, α_c-, β-, and γ-relaxations, as expected for polyethylene. The relaxation strengths of the α_c- and γ-relaxations were found to be dependent on the crystallinity content, verified by means of differential scanning calorimetry. The relaxation molecular dynamics of the γ-relaxation in the solid-state-compressed disentangled sample follows a Vogel–Fulcher–Tammann–Hesse trend, suggesting a dynamic glass-to-rubber transition. The same trend is not found for the γ-relaxation of both melt-state-processed samples, thus suggesting a role of crystalline polydispersity and entanglement density in the free volume of the amorphous segments. Read more

Future Research

Dielectrics are a class of materials that are utilized in energy storage devices like capacitors that store and release energy by reorienting dipoles and charges under the influence of externally applied electric fields. The key elements at play in complex dielectrics are permittivity, conductivity, and dielectric loss and depend across different length scales, from molecular interactions to macroscopic architecture. As a future professor, my ambition is to pioneer the development of sustainable multi-functional polymer-based composite materials to enable next-generation energy storage solutions that are efficient, reliable, and environmentally responsible. Through interdisciplinary collaboration and integration of fundamental polymer physics with industrial application, the work creates a strategic platform for innovation that could extend to flexible electronics, solid-state batteries, and lightweight energy systems. Our efforts will revolve around the fundamentals and engineering aspects of energy storage, approaching it from three different directions, as seen below.