IMX Seminar Series - Multiscale Materials by Design: From Additive Manufacturing to Self-Assembly

The ability to precisely dictate material structure over multiple length scales — from molecular composition to material microstructure to macroscale architecture — to obtain enhanced or previously impossible material properties, is key to the development of new technologies that could help tackle many of the sustainability challenges facing society today. As such, there have been significant interest in developing synthetic and manufacturing strategies
that enable the fabrication of materials with precise form and function. In this seminar, I will highlight two such strategies, additive manufacturing (AM) and self-assembly, and discuss how rational polymer design can enable the manufacturing of advanced materials at varying length scales.
At the micro- to centimeter length scale, I will discuss how in-situ materials synthesis can be used with polymer AM to fabricate nano/micro-architected ceramics and metals. Central to this strategy is the printing of polymers that contain the necessary precursors for the in-situ synthesis of the desired inorganic material, i.e. printing a “chemical reactor”. To demonstrate this concept, I will
show how polymer gels can be designed to undergo solution combustion synthesis for the manufacturing of a wide variety of complex metal oxides, metals, and alloys, providing us with a versatile and accessible method for ceramic and metal AM.
Taking it a length scale smaller into the nano- to micrometer regime, I will discuss how polymer grafted nanoparticles that have supramolecular recognition groups at their chain ends can be used to form 3D ordered nanoparticle superlattices. I will briefly show that these nanoparticle superlattices can be designed to undergo a phase transition and exhibit twinning, and discuss how unlocking these mechanisms in nanoparticle superlattices can enable us to create complex
hierarchical materials with augmented properties.
Together, these demonstrations highlight how rational polymer design can be used to increase the complexity of materials made via additive manufacturing and self-assembly, expanding our ability to design and manufacture materials with precise form and function.
Bio: Daryl W. Yee is currently a tenure-track assistant professor in the Institute of Electrical and Micro Engineering at EPFL. He was previously a postdoctoral associate at MIT and obtained his Ph.D. in Materials Science from Caltech in 2020. Daryl was also a Young National University of Singapore Fellow, and his work has been featured in the ACS Polymer Division’s ‘Excellence in Graduate Polymer Research’. Prior to Caltech, he received his B.Eng in Materials Science and Engineering from Imperial College London.