Session: 03-04-01: Emerging Materials Technology

Paper Number: 120816

120816 - Radio Frequency Heating of Healable Polymeric Composites 

Fiber-reinforced plastics (FRP) with superior strength- and stiffness-to-weight ratios are replacing their metal counterparts in a wide variety of structural applications. FRPs are projected to represent a $31 Billion market by 2024, driven by the soaring demand in the automotive, aerospace, sports equipment and interestingly in circuit boards. However, the principal limitations of FRP are their brittle failure, insufficient fatigue life and poor recyclability, which results in deficiencies in terms of performance, cost, safety, and reliability of structural components. Consequently there is great interest in developing new concepts for fatigue-resistant, tough and re-processable/sustainable FRP. To address the issue of recyclability, reprocessability and reusability of polymeric systems, the molecular network structure of polymers must be considered. We show that a new class of materials called vitrimers that fall under the category of polymers with covalent adaptive network can be instrumental in addressing these challenges. We found that vitrimeric system, reusability (reversing damage and fatigue) can be achieved repeatedly, by heating the material to above its topology freezing transition temperature. The recent discovery that carbon materials can heated using electric fields in the radio frequency range (RF, 1–200 MHz) provides an interesting opportunity for heating such materials in an energy efficient, out-of-oven, and non-contact manner. Using this approach, we show that fatigue failure in vitrimers and in carbon-fiber reinforced vitrimers (vCFRP) can be postponed indefinitely. Such vCFRPs could open the door to future materials, in which natural aging and fatigue processes can be periodically reversed, so as to guarantee safe and reliable long-term operation of composite for various applications.

Presenting Author: Aniruddh Vashisth University of Washington

Presenting Author Biography: Prof Aniruddh Vashisth is an Assistant Professor at University of Washington, Seattle. Aniruddh's main areas of interest are in the discovery, development, and deployment of sustainable materials for applications in mechanical, aerospace, materials, and transportation industries. He did his postdoc in Chemical Engineering from Texas A&M, PhD in Engineering Mechanics from Penn State and Bachelor’s in Civil Engineering from IIT-BHU, India. His group focuses on understanding the underlying physics of sustainable materials using a closely coupled experimental and theoretical approach. Specifically, his group has two focal areas: (a) sustainability in processing to develop novel, energy-efficient methods for ultrafast synthesis and fabrication of materials and (b) discovering new material chemistries using molecular dynamics and machine learning. In the future, we hope to converge these two areas of thrust to synthesize new chemistries using novel synthesis methodologies. Aniruddh molecular dynamics frameworks that has been implemented in multiple software including Software for Chemistry of Materials ADF and LAMMPS. Additionally, Aniruddh has published more than 30 peer-reviewed journal articles and holds 4 patents (granted and pending) on application of RF heating for material processing. His work is funded by companies and federal agencies such as The Boeing Company, Department of Energy, Microsoft, Lynntech, Navy, and Army.