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We report a rapid route to reclaim carbon fiber (CF) fabric and monomeric chemicals from amine-epoxy CF-reinforced polymer (CFRP) composites. We use a reaction that occurs in molten NaOH- KOH eutectic to selectively cleave aryl ether and amine linkages, which involves two temperature-dependant mechanisms. Bisphenol-A is isolated in up to quantitative yields, and recovered CF fabric is remanufactured into 2nd-generation CFRPs. 

Carbon fiber reinforced polymer (CFRP) composites are uniquely essential materials in the aerospace, automobile, energy, sporting, and an increasing number of other industries. Consequently, we are amassing an accumulation of CFRP waste latent in value. Electrochemical techniques to recycle carbon fiber reinforced polymers have recently emerged as viable methods to remove the composite matrix from these materials and recover fibers. In many of these techniques, the composite is immersed in a solvent and acts as an electrochemical anode while a voltage is applied to the electrolytic cell. Still, few methods leverage the conductivity of the composite to mediate its own disassembly. We have introduced an electrolytic method that leverages this conductivity to electrolyze acetic acid to form methyl radicals that cleave the C-N bonds of the epoxy matrix and cleanly separate ordered fibers from the matrix. This talk will discuss the motivation and development for this new electrochemical method and explain the chemical mechanism through which it works. 

We introduce an electrochemical approach to recycle carbon fiber (CF) fabrics from amine-epoxy carbon fiber-reinforced polymers (CFRPs). Our novel method utilizes a Kolbe-like mechanism to generate methyl radicals from CH 3 COOH to cleave C–N bonds within epoxy matrices via hydrogen atom abstraction. Recovered CFs are then remanufactured into CFRPs without resizing. 

Most students enter college without any exposure to polymer science, which leads to the poor understanding and slow implementation of plastics recycling programs in the United States. To address the knowledge gap in chemical recycling, we introduce a 2-part laboratory experiment that was conducted in multiple high schools and public outreach events to demonstrate the depolymerization of PET via aminolysis and the remanufacturing of cleaved PET fragments into a new aramid polymer. Student experiences were evaluated with two post-lab assignments. 

This presentation will describe conditions for the use of oxygen as a reagent for the selective cleavage of thermoset composites. Carbon fiber-reinforced polymer (CFRP) composites have a prominent role in aviation, sporting goods, marine, and other manufacturing sectors and are accumulating en masse as waste, both at end-of-life and as manufacturing defects. We have recently introduced a method to use oxygen itself along with an appropriate catalyst selectively to disassemble such fully-cured composite wastes to recover both ordered carbon fiber sheets and organic materials suitable for re-manufacturing of second-life resin systems. 

This chapter describes two mechanical expansion microscopy methods with accompanying step-by-step protocols. The first method, mechanically resolved expansion microscopy, uses non-uniform expansion of partially digested samples to provide the imaging contrast that resolves local mechanical properties. Examining bacterial cell wall with this method, we are able to distinguish bacterial species in mixed populations based on their distinct cell wall rigidity and detect cell wall damage caused by various physiological and chemical perturbations. The second method is mechanically locked expansion microscopy, in which we use a mechanically stable gel network to prevent the original polyacrylate network from shrinking in ionic buffers. This method allows us to use anti-photobleaching buffers in expansion microscopy, enabling detection of novel ultra-structures under the optical diffraction limit through super-resolution single molecule localization microscopy on bacterial cells and whole-mount immunofluorescence imaging in thick animal tissues. We also discuss potential applications and assess future directions.