Redox-Active Organic Materials: From Energy Storage to Redox Catalysis
Not Available
25 ENERGY STORAGE↗
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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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High-Strength Organic–Inorganic Composites with Superior Thermal Insulation and Acoustic Attenuation
Not Available
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
A Trifunctional Cyclohexasilane for Branched Poly(cyclosilane)s
The poly(cyclosilane)s are a class of hybrid inorganic-organic polymers with an all Si–Si backbone, arranged into repeating cyclohexasilane motifs, and mixed methyl and hydro side chains. The synthesis of a densely functionalized cyclosilane with three-fold symmetry enabled copolymerization studies yielding poly(cyclosilane)s with variable amounts of branching. The properties of the novel branched poly(cyclosilane)s were investigated and it was found that branching led to less volatilization during pyrolysis in an inert atmosphere, suggesting the utility of poly(cyclosilane)s for applications as preceramic polymers.
Coschigano, Marissa G. [Johns Hopkins University, ↗
A Cable Condition Monitoring Strategy for Safe and Reliable Plant Operation
Electrical cables provide essential functions, such as delivery of power or instrumentation signals for monitoring systems. Most cables installed in industrial applications are constructed with organic polymer insulations that can become brittle, crack, or degrade over time from exposure to harsh environmental conditions, such as elevated temperatures, moisture, vibration, mechanical shock, and radiation. This paper describes an overall strategy for assessing the health and managing the aging of cables during the operating life of an industrial facility. This strategy involves performing condition assessments and monitoring of electrical cables using both in situ and laboratory testing techniques. It includes in situ testing to identify anomalies in the circuits, such as degraded terminations, splices, connections, and degraded sections of cable insulation, as well as as-found evaluations to determine the current condition of installed cables. Furthermore, these cable condition evaluations provide important information about the current state of the cable circuits. Moreover, the test results can be used to trend/monitor age-related degradation and estimate the remaining useful life of installed cables.
36 MATERIALS SCIENCE↗
Dielectric properties of neutron and proton irradiated polymeric nanocomposite insulation for superconducting magnets of fusion power plants
Studies on radiation-resistant electrical insulation for superconducting magnets of nuclear fusion power plants are discussed. Metal oxide nanoparticle-incorporated organic polymer composite (MONAP) insulation films were manufactured and studied for their dielectric breakdown strength after exposure to neutrons and proton radiation at varying levels. Samples with up to 5 wt% of nanoparticles (NPs) of SiO 2 , MgO, and ZrO 2 were studied. The samples were exposed to radiation of up to 2 × 10 16 neutrons/cm 2 and 200 Mrad of protons. The addition of the nanoparticles improved the radiation resistance of the MONAP, and the performance depended on the type of NPs and the radiation exposure. Dielectric breakdown measurements at 77 K showed little degradation. Enhancement of dielectric strength was observed in some instances.
36 MATERIALS SCIENCE↗
Enhancing the performance of solvent-borne poly(ethyl methacrylate) coatings for high-power laser applications via low-temperature drying
Organic polymers are a versatile class of materials employed in a broad range of optical coating applications. However, their use as coatings in high-power laser applications, particularly in the UV spectral region, has been limited in scope due to their relatively low laser-induced damage thresholds (LIDTs), which decrease further with exposure to multiple pulses. This study explores the effect of post-deposition drying temperature and residual solvent on the LIDT of solvent-borne polymer coatings. In this work, poly(ethyl methacrylate) (PEMA) coatings were deposited by first spin coating solutions of PEMA (dissolved in 2,2,2-trichloroethanol (TCE)) onto fused silica substrates, then baking at temperatures of either 130°C (soft-bake) or 180°C (hard-bake). Analysis of the two coatings revealed that the soft-bake coating retained a significant amount of TCE within the polymer matrix, which functioned to plasticize the coating and reduce internal stress. The laser-induced damage resistance of the two coatings was evaluated using 351-nm, 1-ns laser pulses. The testing protocols included single-pulse (1-on-1), 1-pulse ramp (R-on-1), and a 1000-pulse ramp (1000R-on-1) test. The results showed that the plasticized, soft-bake coating exhibits a significantly increased LIDT, especially for multipulse irradiation conditions.
36 MATERIALS SCIENCE↗
Controlled Pyrolysis: A Robust Scalable Composite Recycling Technology
The reinforced composites industry is facing significant challenges in handling the scrap composite material from automobile manufacturing, the wind turbine industry, and others. The fibers in the material, whether they be carbon, glass, or other materials have commercial value if they can be recovered successfully. Successfully means the fibers are clean with no sizing or other binders and have adequate strength and physical properties that would allow them to be economically reprocessed into valuable product. The composites recycling project was an industry-collaborative effort to develop a composite recycling technology using controlled pyrolysis. Through the recycling of scrap and end-of-life (EOL) cured composite materials, this pilot study was intended to create a business case by realizing a cost-effective means for recycling EOL and production scrap composite materials, ultimately reducing the volume of composite materials destined for landfill. The project was led by the Institute for Advanced Composites Manufacturing Innovation (IACMI), the American Composites Manufacturers Association (ACMA), Oak Ridge National Laboratory (ORNL), Continental Structural Plastics (CSP) a Teijin Group Company, CHZ Technologies, and A. Schulman with support from Owens Corning, John Deere, General Electric (GE), Ashland LLC, and Plastics Europe (CEFIC). The team studied and tested CHZ Technologies’ controlled pyrolysis system, known as the Thermolyzer TM , which operates on a scalable basis to convert organic polymer materials into a clean synthesis gas and char containing the recoverable carbon and glass fiber reinforcement. The recoverable energy contained in the input polymers creates the synthesis gas that can be used to provide heat to the Thermolyzer TM primary reactor in a sustainable manner. That is, once the Thermolyzer TM is started with a small amount of external natural gas, the synthesis gas that is created from the polymers will continue to operate the burners so long as feedstock is supplied. The reinforcing fiber materials remaining in the solid phase char were separated and cleaned for re-use in other polymer systems based on the retained properties of the fibers. The study created reports (attached in the appendix) on the Mass and Energy Balances, syngas analytics, VOC assessment, yield analysis and other analytics necessary for a Techno-Economic Analysis (TEA) to quantify the economic impact of the recovery and sustainable re-use of the carbon and glass fibers. The process consisted of 4 steps: Selection of 4 samples of cured composite waste materials from project partners interested in materials recycling and recovering the reinforcing fibers for best case re-use. The materials included glass fiber (GF) polyester/vinyl ester automotive SMC from CSP, GF epoxy balsa/PVC foam wind blades from GE, carbon fiber (CF) epoxy wind blade laminated spar caps from GE, and GF/CF epoxy hybrid assembly from John Deere. Processing the waste composite samples into 1-2” shreds. Packaging the shredded composites into bulk sacks on international shipping pallets for shipment to KUG in Forst (Lausitz), Germany. Pyrolysis of the shredded composites under controlled conditions designed for each polymer system. Collecting samples of the gas and char for analysis. Shipping the char containing the CF/GF back to the US for the next steps of testing the fibers and developing protocols for sustainable re-use of the fibers in composite applications.
36 MATERIALS SCIENCE↗
Imaging Intact Filamentous Fungi from Spore to Hyphal Tip on the Nanoscale
Previously, the Pacific Northwest National Laboratory was limited by a 3-order of magnitude gap in resolution for direct 2-D and 3-D imaging of chemical, biological, energy and materials science systems. Our imaging instrumentation could directly visualize 3-D ultrastructure without labeling at resolutions less than 10-nanometers or greater than 10-micrometers. To address this gap, we procured and commissioned a Sigray NanoFast Bio-Lambda laboratory-based x-ray nanotomography system. This equipment provides the capability to image through tens of micrometers of organic materials at down to 35-nanometer resolution to bridge the nanoscale to the mesoscale for biological systems, organic polymers, environmental and particulate samples.
47 OTHER INSTRUMENTATION↗
Cross-Feeding of a Toxic Metabolite in a Synthetic Lignocellulose-Degrading Microbial Community
The recalcitrance of complex organic polymers such as lignocellulose is one of the major obstacles to sustainable energy production from plant biomass, and the generation of toxic intermediates can negatively impact the efficiency of microbial lignocellulose degradation. Here, we describe the development of a model microbial consortium for studying lignocellulose degradation, with the specific goal of mitigating the production of the toxin formaldehyde during the breakdown of methoxylated aromatic compounds. Included are Pseudomonas putida, a lignin degrader; Cellulomonas fimi, a cellulose degrader; and sometimes Yarrowia lipolytica, an oleaginous yeast. Unique to our system is the inclusion of Methylorubrum extorquens, a methylotroph capable of using formaldehyde for growth. We developed a defined minimal “Model Lignocellulose” growth medium for reproducible coculture experiments. We demonstrated that the formaldehyde produced by P. putida growing on vanillic acid can exceed the minimum inhibitory concentration for C. fimi, and, furthermore, that the presence of M. extorquens lowers those concentrations. We also uncovered unexpected ecological dynamics, including resource competition, and interspecies differences in growth requirements and toxin sensitivities. Finally, we introduced the possibility for a mutualistic interaction between C. fimi and M. extorquens through metabolite exchange. This study lays the foundation to enable future work incorporating metabolomic analysis and modeling, genetic engineering, and laboratory evolution, on a model system that is appropriate both for fundamental eco-evolutionary studies and for the optimization of efficiency and yield in microbially-mediated biomass transformation.
Methylorubrum extorquens↗
Nanoscale resolution of microbial fiber degradation in action
The lives of microbes unfold at the micron scale, and their molecular machineries operate at the nanoscale. Their study at these resolutions is key toward achieving a better understanding of their ecology. We focus on cellulose degradation of the canonical Clostridium thermocellum system to comprehend how microbes build and use their cellulosomal machinery at these nanometer scales. Degradation of cellulose, the most abundant organic polymer on Earth, is instrumental to the global carbon cycle. We reveal that bacterial cells form ‘cellulosome capsules’ driven by catalytic product-dependent dynamics, which can increase the rate of hydrolysis. Biosynthesis of this energetically costly machinery and cell growth are decoupled at the single-cell level, hinting at a division-of-labor strategy through phenotypic heterogeneity. This novel observation highlights intrapopulation interactions as key to understanding rates of fiber degradation.
59 BASIC BIOLOGICAL SCIENCES↗
Methods for preparation of concentrated graphene ink compositions and related composite materials
A rapid, scalable methodology for graphene dispersion and concentration with a polymer-organic solvent medium, as can be utilized without centrifugation, to enhance graphene concentration.
36 MATERIALS SCIENCE↗
Methods for preparation of concentrated graphene ink compositions and related composite materials
A rapid, scalable methodology for graphene dispersion and concentration with a polymer-organic solvent medium, as can be utilized without centrifugation, to enhance graphene concentration.
36 MATERIALS SCIENCE↗
Nanoporous Catalysts for Biomass Conversion
Transforming plant biomass to biofuel and chemicals has become a global effort as results of increasing fuel demand but diminishing fossil-based energy preservation and rising concerns of climate and environmental impact. Various conversion routes involving thermochemical and biological conversions have been established and well-studied. Heterogeneous catalysis is playing a critical role in the biomass conversion and, with some unique catalytic properties, nanoporous catalysts have been extensively utilized in catalytic process of biomass conversion and exhibited exciting catalytic performance. This chapter will be devoted to nanoporous catalysts used in biomass conversion. It will start with a brief introduction of current biomass conversion technologies and then a detailed review of the application of various nanoporous materials in a large diversity of catalytic reactions in biomass conversion. The nanoporous materials include zeolites and zeotypes, metal-organic frameworks (MOFs), nanoporous carbons and carbon nitrides, nanoporous oxides, hydroxides and complex oxide forms, porous organic polymers (POPs), and porous metals.
Shi, Hui↗
Methods for preparation of concentrated graphene ink compositions and related composite materials
A rapid, scalable methodology for graphene dispersion and concentration with a polymer-organic solvent medium, as can be utilized without centrifugation, to enhance graphene concentration.
36 MATERIALS SCIENCE↗
Nitrogen-sulfur-carbon nanocomposites and their application as cathode materials in lithium-sulfur batteries
The invention is directed in a first aspect to electron-conducting porous compositions comprising an organic polymer matrix doped with nitrogen atoms and having elemental sulfur dispersed therein, particularly such compositions having an ordered framework structure. The invention is also directed to composites of such S/N-doped electron-conducting porous aromatic framework (PAF) compositions, or composites of an S/N-doped mesoporous carbon composition, which includes the S/N-doped composition in admixture with a binder, and optionally, conductive carbon. The invention is further directed to cathodes for a lithium-sulfur battery in which such composites are incorporated.
25 ENERGY STORAGE↗
Structure and Dispersion of Free and Grafted Polymer in Nanoparticle Organic Hybrid Materials-Based Solutions by Small-Angle Neutron Scattering
Liquid-like Nanoscale Organic Hybrid Materials or NOHMs consisting of polymer grafted nanoparticles have shown great promise in applications, such as electrochemistry and gas separation, due to their enhanced conductivity, tunability, and negligible vapor pressure. Recently, NOHMs are considered to be used as novel electrolytes in Redox Flow Batteries (RFBs). However, to employ NOHMs in redox flow batteries as electrolytes, it is important to understand the conformation and dispersion of NOHMs in the electrochemical milieu. In this work, we report the use of small-angle neutron scattering to probe the structure and dispersion of Jeffamine M2070 polymer grafted to a SiO 2 nanoparticle in an aqueous solution with and without the presence of a supporting electrolyte. Our results indicate that, in the aqueous environment, there exists a large amount of free polymer in the solution that is not grafted to the functionalized nanoparticles. These protonated free polymers, dispersed in the aqueous solvent, may also strongly interact with the grafted polymer layer and greatly affect the neat structure of NOHMs. Thus, there also exist polymers identified as “interacting” polymers to distinguish them from tethered or truly free polymers in the fluid system. The presence of supporting electrolyte shows a greater effect on the structure of NOHMs-based fluid as it not only alters the structure of the free polymer but also hinders the interaction of the polymer with the functionalized nanoparticles. Moreover, the change in the interaction of the Jeffamine M2070 with the functionalized nanoparticles due to the addition of supporting electrolyte has revealed a drastic change in the viscosities of NOHM solutions. Overall, the dispersion of the free polymer, the interaction of the interacting polymer with grafted polymer, and the change in conformation of free polymer and grafted layers with the addition of supporting electrolyte provide valuable insight into the overall scenario of the electrochemical environment of NOHMs. These results can be applied to fine-tune the structure of liquid-like NOHMs and will aid in a better understanding of their performance as potential electrolytes in RFBs.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
A Chlorinated Donor Polymer Achieving High‐Performance Organic Solar Cells with a Wide Range of Polymer Molecular Weight
Abstract In the field of non‐fullerene organic solar cells (OSCs), compared to the rapid development of non‐fullerene acceptors, the progress of high‐performance donor polymers is relatively slow. The property and performance of donor polymers in OSCs are often sensitive to the molecular weight of the polymers. In this study, a chlorinated donor polymer named D18‐Cl is reported, which can achieve high performance with a wide range of polymer molecular weight. The devices based on D18‐Cl show a higher open‐circuit voltage ( V OC ) due to the slightly deeper energy levels and an outstanding short‐circuit current density ( J SC ) owing to the appropriate long periods of blend films and less ([6,6]‐phenyl‐C71‐butyric acid methyl ester) (PC 71 BM) in mixed domains, leading to the higher efficiency of 17.97% than those of the D18‐based devices (17.21%). Meanwhile, D18‐Cl can achieve high efficiencies (17.30–17.97%) when its number‐averaged molecular weight ( M n ) is ranged from 45 to 72 kDa. In contrast, the D18‐based devices only exhibit relatively high efficiencies in a narrow M n range of ≈70 kDa. Such property and performance make D18‐Cl a promising donor polymer for scale‐up and low‐cost production.
Zeng, Anping↗
Influence of Polymer Characteristics on the Self-Assembly of Polymer-Grafted Metal–Organic Framework Particles
Not Available
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗