Mechanically Interlocked Resilient Additives (MIRA)
Abstract
Throughout the performance period of this project, teams from UC Berkeley, GE Research, and the University of Southern Alabama (USA) developed strategies to synthesize and characterize a new class of polymer composites. Based upon the principles of molecularly interlocked molecules (MIMs), the teams generated woven and interlocked covalent organic frameworks (COFs) to be used as filler materials in different polymer systems. The resulting composites were tested for enhanced performance and the filler-matrix interactions were characterized by a variety of techniques. UC Berkeley reported meaningful advancements in the synthesis, characterization, and scaling of metal-free woven and interlocked COFs. Initial target structures were tested for their scalability, which also included an investigation into the accessibility of starting materials. Specifically, methodologies to scale woven COF-506 both by reflux and solvothermal syntheses were developed to reach multi-gram scale. The recycling of metal ions from the demetallation process was achieved via a chemical reduction of copper ions. These studies resulted in two pathways to produce and demetalate imine-linked and amine-linked woven COFs. These findings are directly translatable to other COFs, which poses significant progress in the feasibility of this class of materials. Furthermore, the Berkeley team employed characterization techniques involving 2D solid-state nuclear magnetic resonance (NMR) techniques provided valuable insight into the polymer-COF interactions in the composites. These studies revealed two types of possible interactions between the polymer matrix and the framework fillers. Polymethylmethacrylate (PMMA) showed surface interactions with the woven COFs, which resulted in marginal or no improvements in the mechanical behavior of the resulting composites. However, the interactions of the COF with polyimide (PI) revealed significant spatial closeness between the polymer backbone and the framework.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 16, 2024
- Accession Number
- AD1222451
Entities
People
- Omar M. Yaghi
Organizations
- University of California Regents