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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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At least 541 records · Page 30
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Abstract for CRADA between National Energy Technology Laboratory and American Institute of Chemical Engineers dba RAPID Manufacturing Institute

NETL and RAPID Manufacturing will develop advanced electromagnetic (EM) reactors and catalysts to produce light olefins from alternative feedstocks using CO2 soft oxidation. Light olefins are the building blocks for many plastic products, in addition to synthetic fibers, rubbers, and polymers. This project has the potential to produce high-value light olefins from alternative feedstocks with reduced energy consumption (50-70%), carbon intensity (50-70%), and production cost (15-25%) compared to the traditional olefin production processes.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
NASA NTRS1975

Development of a special purpose spacecraft interior coating, phase 1

Coating formulations were developed consisting of latex blends of fluorocarbon polymers, acrylic resins, stabilizers, modifiers, other additives, and a variety of inorganic pigments. Suitable latex primers were also developed from an acrylic latex base. The formulations dried to touch in about one hour and were fully dry in about twenty-four hours under normal room temperature and humidity conditions. The resulting coatings displayed good optical and mechanical properties, including excellent bonding to (pre-treated) substrates. In addition, the preferred compositions were found to be self-extinguishing when applied to nonflammable substrates and could meet the offgassing requirements specified by NASA for the intended application. Improvements are needed in abrasion resistance and hardness.

Bartoszek, E. J.↗
NASA NTRS1981

Composition and method for making polyimide resin-reinforced fabric

A composition for making polyimide resin reinforced fibers or fabric is discussed. The composition includes a polyfunctional ester, a polyfunctional amine, and an end capping agent. The composition is impregnated into fibers or fabric and heated to form prepreg material. The tack retention characteristics of this prepreg material are improved by incorporating into the composition a liquid olefinic material compatible with the other ingredients of the composition. The prepreg material is heated at a higher temperature to effect formation of the polyimide resin and the monomeric additive is incorporated in the polyimide polymer structure.

Serafini, T. T.↗
NASA NTRS1981

Aspects of the mechanisms of smoke generation by burning materials

An investigation of smoke generation during the burning of natural and synthetic solid materials (relevant to fire safety problems), under simulated fire conditions, is presented. Smoke formation mechanisms, including flaming and nonflaming combustion, are reviewed, and the complex physical, chemical, and electrical processes, important in smoke particulate production, are identified. With reference to the smoke formation mechanisms, measured experimental data are discussed, and include effects of ventilation gas temperature, dependence on material composition, and chemical analysis of smoke particulates. Significant differences in smoke characteristics are observed between flaming and nonflaming conditions, which is attributed to specific differences in controlling mechanisms and resultant ways leading to particulate formation. The effects of polymer substrate properties and effects of additives for a given substrate on smoke properties are also discussed in terms of basic processes. It is shown that many of the measured trends can be interpreted by considering postulated mechanisms of particulate formation.

Bankston, C. P.↗
NASA NTRS1991

Drag reduction in nature

Recent studies on the drag-reducing shapes, structures, and behaviors of swimming and flying animals are reviewed, with an emphasis on potential analogs in vehicle design. Consideration is given to form drag reduction (turbulent flow, vortex generation, mass transfer, and adaptations for body-intersection regions), skin-friction drag reduction (polymers, surfactants, and bubbles as surface 'additives'), reduction of the drag due to lift, drag-reduction studies on porpoises, and drag-reducing animal behavior (e.g., leaping out of the water by porpoises). The need for further research is stressed.

Bushnell, D. M.↗
NASA NTRS2009

Complex Multifunctional Polymer/Carbon-Nanotube Composites

A methodology for developing complex multifunctional materials that consist of or contain polymer/carbon-nanotube composites has been conceived. As used here, "multifunctional" signifies having additional and/or enhanced physical properties that polymers or polymer-matrix composites would not ordinarily be expected to have. Such properties include useful amounts of electrical conductivity, increased thermal conductivity, and/or increased strength. In the present methodology, these properties are imparted to a given composite through the choice and processing of its polymeric and CNT constituents.

Patel, Pritesh↗
NASA NTRS2019

Advanced CMCs, Additive Manufacturing, and Joining/Integration Technologies

An overview of ceramic matrix composite (CMC) and additive manufacturing capabilities at GRC is provided. The additive manufacturing methods include laminated object manufacturing (LOM), binder jetting, 3-D printing, extrusion, direct writing and multi-materials additive manufacturing. Examples are given of GRC's extensive experience in the development and implementation of CMCs in various aerospace systems. Additive manufacturing offers significant advantages in fabricating preforms, ceramics, and CMCs. They will have to be selectively applied to "traditional" components but can also enable new applications. Additive manufacturing of lightweight and multifunctional polymer composites can provide wide ranging properties. Multi-material printing approaches could provide new opportunities to explore and expand the design envelope. Joining and Integration technologies, gaskets and sealants, as well as repair and refurbishment are also keys for Hypersonic applications.

Grady, Joseph E.↗
DOE OSTI2023

One-Component, Vinyl-Functional Fluorosilicone Pastes for Direct Ink Write Additive Manufacturing

In this study, one-component (“all-in-one”) fluorosilicone pastes specifically designed for application in direct ink write (DIW) additive manufacturing (AM) have been developed. They consist of vinyl-functional, methyltrifluoropropyl-containing (MeTfpS) terpolysiloxane base polymer(s), hydrosilyl-functional cross-linker(s), UV-sensitive hydrosilylation catalyst, thixotropic additive, and trimethylsilylated fumed silica filler, with other additives that are optional. Their base polymers were completely amorphous and linear, with molecular weights (M n ) ranging from approximately 7000 to 50,000 and specifically targeted for the viscosity range ideal for DIW. These polymers were prepared by anionic ring-opening polymerizations (A-ROP) of appropriate mixtures of cyclic siloxanes initiated by oligomeric, difunctional tetramethylammonium silanolate in the presence of a difunctional tetramethyldivinyldisiloxane end-blocker and molecular weight regulator. Two series of these terpolymers were prepared: one containing 5 mol % MeTfpS repeat units but varying degrees of polymerization (DP) from 80 to 600 and the other containing 5, 10, and 15 mol % MeTfpS at a constant DP of 600. All polymers contained mostly random distributions of MeTfpS repeat units. The pastes were prepared by speed-mixing, ready for use in DIW, they exhibited ideal thixotropy, long-term (over a year) rheological stability, and can be quickly (within seconds) and permanently cured by room-temperature, UV-activated hydrosilylation in air. The resulting elastomers showed base polymer molecular weight- and composition-dependent stress-induced crystallization (SIC) at higher molecular weights and lower trifluoropropyl contents and tunable Shore A hardness (30A–40A) typical for soft polysiloxane rubbers. Preliminary DIW tests indicated excellent printability with high precision of printed shapes and clearly present these one-component pastes as prime candidates for simple and practical printing of silicone elastomer objects.

36 MATERIALS SCIENCE↗
NASA NTRS2004

ITO-MgF2 Film Development for PowerSphere Polymer Surface Protection

Multi-kilogram class microsatellites with a PowerSphere electric power system are attractive for fulfilling a variety of potential NASA missions. However, PowerSphere polymer surfaces must be coated with a film that has suitable electrical sheet resistivity for electrostatic discharge control, be resistant to atomic oxygen attack, be transparent to ultraviolet light for composite structure curing and resist ultraviolet light induced darkening for efficient photovoltaic cell operation. In addition, the film must be tolerant of polymer layer folding associated with launch stowage of PowerSphere inflatable structures. An excellent film material candidate to meet these requirements is co-sputtered, indium oxide (In2O3) - tin oxide (SnO2), known as 'ITO', and magnesium fluoride (MgF2). While basic ITO-MgF2 film properties have been the subject of research over the last decade, further research is required in the areas of film durability for space-inflatable applications and precise film property control for large scale commercial production. In this paper, the authors present film durability results for a folded polymer substrate and film resistance to vacuum UV darkening. The authors discuss methods and results in the area of film sheet resistivity measurement and active control, particularly dual-channel, plasma emission line measurement of ITO and MgF2 plasma sources. ITO-MgF2 film polymer coupon preparation is described as well as film deposition equipment, procedures and film characterization. Durability testing methods are also described. The pre- and post-test condition of the films is assessed microscopically and electrically. Results show that an approx. 500A ITO-18vol% MgF2 film is a promising candidate to protect PowerSphere polymer surfaces for Earth orbit missions. Preliminary data also indicate that in situ film measurement methods are promising for active film resistivity control in future large scale production. Future film research plans are also discussed.

Hambourger, Paul D.↗
NASA NTRS2026

Influence of Processing Parameters on the Mechanical Properties of 3D Printed Borosilicate Particulate Reinforced Polymer Composites

Emerging composite materials are expanding the potential of additive manufacturing and enabling applications previously restricted by traditional manufacturing methods. The multi-phase nature of these composite materials combined with the complex in-ternal geometry of additively manufactured parts have enabled unique behavior, and potentially new applications. Additionally, these materials can be pyrolyzed to create dense metal, ceramic, and glass parts with geometries typically not achievable by tra-ditional processes. Additive manufacturing of borosilicate glass-based systems can open new applications in nuclear engineering, astronomy, and bone regrowth therapy. To elucidate the process-parameter relationship of borosilicate-polylactic acid (PLA) composites, mechanical testing was conducted and compared with a pure polylactic acid polymer baseline. Test specimens were fabricated by fused-filament fabrication with minimal post-processing. Yield strength, ultimate strength, and elastic modulus were calculated from stress-strain curves. Optical and scanning electron microscopy were conducted to observe the specimen microstructure before and after testing. The highest compressive yield strength for the composite was 28.22 MPa, and the highest compressive yield strength for PLA was 49.30 MPa. Print orientation was found to benefit the composite material but have a detrimental effect on the pure matrix material. An elastic modulus of 2.66 GPa was recorded for the borosilicate-PLA composite at 100% infill, 1 shell wall, and layer lines parallel to compression axis. Microscopy revealed that lower modulus composite specimens had the particulates re-distributed within the matrix. Tensile testing was done according to a polymer testing standard, which caused difficulties obtaining consistent fracture within the gauge length.

mechanical testing↗
DOE OSTI2023

Additive Manufacturing of Self‐Sensing Carbon Fiber Composites

Carbon fiber-reinforced polymer (CFRP) composites have gained substantial attention across various industries owing to their exceptional mechanical properties and lightweight nature. The emergence of additive manufacturing technologies brings new opportunities to the industry, offering advantages such as design freedom, rapid prototyping, and customization. However, the fabrication of CFRP composites through 3D printing techniques poses challenges pertaining to low resolution and limitations in complex geometry realization. This work introduces digital light processing printing as a versatile, high-resolution method ideal for CFRP composite fabrication. Furthermore, the development and characterization of CFRP are focused on and the manipulation of mechanical properties through variations in matrix resins and fiber loadings is investigated, showcasing the versatility of CFRP composites for tailored applications. Additionally, the integration of self-sensing capabilities in CFRP structures is explored, which opens up opportunities for applications in smart components for automotive and structural health monitoring.

carbon fiber composites↗
DOE OSTI2023

Reaction Current Heterogeneity at the Interface between a Lithium Electrode and Polymer/Ceramic Composite Electrolytes

Although lithium metal anodes are expected to increase the energy density of next-generation batteries, dendrite growth during charge remains a major bottleneck preventing widespread implementation. Composite solid electrolytes with ceramic particles embedded in a polymer matrix have the potential to prevent dendrites owing to the higher mechanical stiffness while also possessing the flexibility to maintain contact with the electrode. However, microscopically, the different mechanical and electrochemical properties of the polymer and ceramic domains can cause inhomogeneous charge transfer at the Li/electrolyte interface, which can lead to nonuniform Li deposition and propagation of dendrites. Here, we computationally examine the coupled electrochemical, transport, and mechanical processes at the interface to determine the propensity for dendrite formation and possible approaches to mitigate this issue. Predictions of two possible microstructures at the interface, namely, (i) where both the polymer and ceramic come in contact with Li metal and (ii) when only the polymer comes in contact with Li metal, suggest that the former has a greater tendency for nonuniform plating. In addition, predictions suggest that minimizing the interfacial resistance between polymers and ceramics and incorporating interlayers between the electrode and electrolyte help mitigate current heterogeneity. In conclusion, these predictions provide guidance for experimental approaches to prevent dendrites in composite electrolytes.

25 ENERGY STORAGE↗
NASA NTRS2018

Mechanoresponsive Healing Polymers

Methods are provided to produce new mechanoresponsive healing systems. Additionally, various embodiments provide a two tier self-healing material system concept that provides a non-intrusive method to mitigate impact damage in a structure ranging from low velocity impact damage (e.g., crack damage) to high velocity impact damage (e.g., ballistic damage.) The various embodiments provide the mechanophore linked polymer PBG-BCB-PBG. The various embodiments provide methods for synthesizing PBG-BCB-PBG.

Gordon, Keith L.↗
DOE OSTI2025

Investigating Fast Scanning Calorimetry and Differential Scanning Calorimetry as Screening Tools for Thermoset Polymer Material Compatibility with Laser-Based Powder Bed Fusion

As additive manufacturing (AM) technology has developed and progressed, a constant topic of research in the area is expanding the library of materials to be used with these techniques. Among AM methods that utilize polymers, laser-based powder bed fusion (PBF-LB) has preferentially used thermoplastic polymers as its starting materials, but the deposition and material joining method employed in PBF-LB may also be compatible with powdered thermoset polymer precursors as feedstocks. To assess the compatibility of candidate thermosetting polymers and PBF-LB, characterization techniques and protocols that link fundamental material behavior to material behavior in the processing environment are needed. Therefore, the objectives of this work are to compare the curing behavior measured with two different calorimetry techniques that can operate in different heating rate regimes, differential scanning calorimetry (DSC) and fast scanning calorimetry (FSC), and to assess the capabilities of these techniques to act as materials screening tools for PBF-LB. A commercial polyester powder coating is used as a model material to evaluate the potential of obtaining complimentary information for material screening through a combination of calorimetry methods, and its non-isothermal curing behavior is measured at heating rates between 5 °C/min and 7500 °C/min. Curing exotherms are observed with both calorimetry techniques, and comparing the enthalpy associated with curing shows that incomplete curing occurs at higher heating rates, with relative conversion values of approximately 30%. The curing data are fit with two isoconversional models, Friedman and Starink, which show a reduced activation energy at higher heating rates as well, signifying a lower barrier to curing at the conditions used in the FSC experiments. Overall, the results of this work indicate that using these two calorimetry techniques as tiered screening tools can provide valuable information about how curing may proceed in PBF-LB and inform materials selection and design activities for additive manufacturing.

36 MATERIALS SCIENCE↗
NASA NTRS1982

Synthesis and characteristics of poly/bisdichloromaleimides/

The characteristics of six bisdichloromaleimides with different aromatic structures are investigated. The compounds are prepared by reacting 2,3-dichloromaleic anhydride with 1,5-diaminonaphthaline; bis (m-aminophenyl)methylphosphine oxide; 2,5-bis (p-aminophenyl) 1,3,4-oxadiazole; 3,3-bis (p-aminophenyl)phthalide; 9,9-bis (p-aminophenyl) fluorene; 10,10-bis (p-aminophenyl)anthrone. Dynamic thermogravity is used to determine the effect of structural differences on the thermal characteristics of these compounds. These compounds are polymerized by nucleophilic displacement of chlorine with 9,9-bis (p-aminophenyl)fluorene. The polymers are then characterized by IR spectroscopy and reduced viscosity measurements. The anaerobic char yields of these polymers at 800 C are found to range from 55-60%. A complete loss of weight is observed between 600-650 C in the presence of air. In addition, the thermal cross-linking of these polymers is investigated.

Varma, I. K.↗
DOE OSTI2022

Nanoscale Hybrid Electrolytes with Viscosity Controlled Using Ionic Stimulus for Electrochemical Energy Conversion and Storage

As renewable energy is rapidly integrated into the grid, the challenge has become storing intermittent renewable electricity. Technologies including flow batteries and CO 2 conversion to dense energy carriers are promising storage options for renewable electricity. To achieve this technological advancement, the development of next generation electrolyte materials that can increase the energy density of flow batteries and combine CO 2 capture and conversion is desired. Liquidlike nanoparticle organic hybrid materials (NOHMs) composed of an inorganic core with a tethered polymeric canopy (e.g., polyetheramine (HPE)) have a capability to bind chemical species of interest including CO 2 and redox-active species. In this study, the unique response of NOHM-I-HPE-based electrolytes to salt addition was investigated, including the effects on solution viscosity and structural configurations of the polymeric canopy, impacting transport behaviors. The addition of 0.1 M NaCl drastically lowered the viscosity of NOHM-based electrolytes by up to 90%, reduced the hydrodynamic diameter of NOHM-I-HPE, and increased its self-diffusion coefficient, while the ionic strength did not alter the behaviors of untethered HPE. This study is the first to fundamentally discern the changes in polymer configurations of NOHMs induced by salt addition and provides a comprehensive understanding of the effect of ionic stimulus on their bulk transport properties and local dynamics. These insights could be ultimately employed to tailor transport properties for a range of electrochemical applications.

25 ENERGY STORAGE↗
DOE OSTI2025

LiNi0.8Mn0.1Co0.1O2 Thin Films Prepared by Polymer-Assisted Deposition for the Study of Cathode-Electrolyte Interphases in Lithium-Ion Batteries

High-nickel layered oxide cathodes such as LiNi0.8Mn0.1Co0.1O2 (NMC811) are critical for next-generation lithium-ion batteries (LIBs) due to their superior energy density and reduced reliance on cobalt. However, many Ni-rich cathodes suffer from rapid capacity fade and structural instability originating from complex interfacial reactions at the cathode-electrolyte interface. Traditional composite electrodes exhibit degradation mechanisms that are challenging to quantitatively understand due to additives, including binders and carbon black. In this study, we demonstrate a new synthesis approach for binder- and additive-free NMC811 thin films using polymer-assisted deposition (PAD). PAD-NMC811 are model thin-film cathodes for investigating interfacial phenomena that can be obscured in composite cathodes. Structural and chemical characterization by X-ray diffraction, soft X-ray absorption spectroscopy, and atomic force microscopy show that PAD-NMC811 films possess high phase purity, crystallinity, chemical homogeneity, and morphological uniformity. Electrochemical analyses using cyclic voltammetry and galvanostatic cycling revealed electrochemical behavior consistent with that of composite electrodes, along with a moderate capacity fade indicative of cathode-electrolyte interphase (CEI) formation. Our findings illustrate the effectiveness of PAD synthesis of thin films tailored for detailed mechanistic studies, which offer critical insights into CEI evolution and cathode degradation pathways.

25 ENERGY STORAGE↗