Available on-demand - S.CT04.06.10
Interphase Engineering for 1D and 2D Nanocarbon-Included Functional Composites
Kenan Song1,Weiheng Xu1,Sayli Jambhulkar1,Dharneedar Ravichandran1
Arizona State University1
The interface and interphase between a matrix and the fillers will influence the stress transfer, energy transport, stabilization of dispersant, degree of confinement or bonding, and, other new property generations. Both physical (e.g., molecular wrapping on filler surfaces or self-assembly) and chemical (e.g., surface functionalization) can modify the matrix-filler interfacial interactions. This talk will introduce two kinds of interface/interphase manipulations for precisely controlling nanoparticle morphologies. Our unique manufacturing and the resulted advanced composites have potential applications in wearable, robotics, biomedical, and other areas.
The first example was the use of polymer-graphene interphase design to achieve two dimensional (2D) nanoparticle orientation management. As well known that atomically thin 2D materials are challenging to be aligned as compared with their allotropes, such as carbon nanotubes. Free-standing graphene in ambient conditions will wrinkle, crumple or fold due to their instability of thermodynamic states. Our unique design of the different phases consisted of macromolecules and 2D graphene allowed the material system to take advantage of the interphase structural evolutions for confining, exfoliating and aligning the nanoparticles. Different polymers such as semicrystalline polyvinyl alcohol (PVA) and thermoplastic polyurethane were used to study the interphase engineering and their influence on graphene or similar nanocarbons for mechanical enhancement or functionality incorporations. The unique material system of composite fibers were used as piezo- and chemi-resistive sensors.
The second demonstration utilized layer-by-layer-based deposition techniques. Both additive manufacturing (e.g., 3D printing) and dip-coating methods were used on the same processing platform. One dimensional carbon nanofibers (CNF) were used as an example to be selectively deposited on polymer surfaces with pre-printed patterns. The control of the surface patterns and the nanoparticle assembly conditions (e.g., thermodynamic parameters, nanoparticle interactions, solid-liquid-air contact lines, etc.) led to selective deposition and preferential alignment of CNF. As a result, the conductive paths on the substrate were developed to be anisotropic; following this characterization, the multifunctional sensitivity to strain, temperature, chemical liquids and volatile organic compounds (VOCs) were also displayed.
Jambhulkar, S., Xu, W., Ravichandran, & Song, K. (2019). Selective Deposition and Preferential Alignment of Nanoparticles on Surface Patterns. Under review.
Ravichandran, D., Xu, W., Franklin, R., Kanth, N., Jambhulkar, S., Shukla, S., & Song, K. (2019). Fabricating Fibers of a Porous-Polystyrene Shell and Particle-Loaded Core. Molecules, 24(22), 4142.
Xu, W., Jambhulkar, S., Verma, R., Franklin, R., Ravichandran, D., & Song, K. (2019). In situ alignment of graphene nanoplatelets in poly (vinyl alcohol) nanocomposite fibers with controlled stepwise interfacial exfoliation. Nanoscale Advances, 1, 2510-2517.