2024-2025 Kavli Heising-Simons Junior Fellow
Faculty Advisor: Professor Ting Xu
Tiffany Chen is a Chemistry PhD candidate in Ting Xu's group, working on polymer grafted nanoparticles (PGNPs) based single component composites (SCCs). She received her B.S. in Chemistry at UC San Diego in 2017 where she worked for Michael Sailor on surface modification of porous silicon nanomaterials for sensor application. In her free time, she enjoys puzzles, arts and crafts and baking.
Tiffany’s research focuses on understanding the chain conformation of grafted polymers under nanoconfinement by using their mechanical properties as readout. As artificial atoms, PGNPs self-assemble to replicate crystal structures seen in metal and ceramic, while accessing a wide range of organic/inorganic composition. The interfacial curvature provides a versatile platform to modulate polymer phase behavior at the single chain, segmental and cluster levels, which can propagate through the structures to affect microscopic properties. In previous study, Tiffany showed when single PGNP was probed under stress, the grafted glassy polymers can exhibit behaviors similar to brittle and ductile materials. These different behaviors can be explained by the heterogeneity in the radial and lateral organization of the grafted polymers on reduced curved surface. This leads to new design principles for PGNP-based SCCs.
As a Kavli ENSI Fellow, Tiffany will continue to investigate the effect of local surface curvature on the chain conformation of grafted polymers under nano-confinement by utilizing faceted nanoparticles. Faceted particles based on noble metal, which have significant distance-dependent plasmonic properties, polymer chains dissipating energy can lead to optical changes. Coupled with single particle indentation, they provide an ideal platform to interrogate how PGNP-based SCCs respond to external stress. Knowledge gains will pave the path toward multi-functional nanocomposites.