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Surface-Modified Nanoparticles Made From High-Molecular-Weight Carboxylic Acids

Starting materials include aluminum oxy hydroxides pretreated with low molecular-weight carboxylic acids. Nanoparticles Made From High-Molecular-Weight Carboxylic Acids An improved class of alumoxanes and a method of synthesizing them have been invented. Alumoxanes are aluminum oxy hydroxide particles that have been modified with compounds containing carboxylic acid groups. For typical applications in which alumoxanes are required to be compatible with polymers, it is desirable that the modifying compounds be carboxylic acids that have high molecular weights (>500 Daltons) and/or are somewhat hydrophobic (characterized by solubility <5% in boiling water). Heretofore, the hydrophobicity of such compounds has made it difficult or impossible to synthesize alumoxanes in sufficiently high yields in acceptably short reaction times, and the alumoxane products have exhibited nonuniformities, both within and between batches. The present invention overcomes these shortcomings of prior approaches to synthesis of alumoxanes.

Posted in: Briefs, TSP

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NASA PS400 High-Temperature Solid Lubricant Coating

The material provides low friction and wear over a wide temperature range. John H. Glenn Research Center, Cleveland, Ohio NASA has an ongoing need for high-temperature solid lubricant coatings to reduce friction and wear in turbine engines, rocket engines, and other mechanical systems. Such lubricants must be thermally and chemically stable in air, vacuum, and reducing environments like hydrogen. Traditional lubricants like oil, grease, and PTFE (Polytetrafluoroethylene), and even more exotic solid lubricants like graphite and molybdenum disulphide, lack such capabilities. The key problem is to identify and formulate a material that possesses good mechanical properties, long-term environmental durability, and acceptable friction and wear-reducing characteristics while being practical to apply to bearings, seals, and other mechanical components.

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Triple Orthogonal Disk Polymer Discrete Space for Cryogenic Feedline Insulation

A new material provides a superior, robust insulation for cryogenic feed lines. John H. Glenn Research Center, Cleveland, Ohio NASA vehicles using cryogenic propellants and systems need improved cryogenic storage and transfer, including insulation for cryogenic transfer/feed lines. Wrapped multi-layer insulation (WMLI) is an innovative, next-generation, high-performance multilayer insulation designed specifically for cryogenic plumbing systems. WMLI uses Quest Thermal Group’s Discrete Spacer Technology to precisely control layer spacing, layer density, and minimize system heat flux. A customized discrete spacer, the Triple Orthogonal Disk (TOD) spacer, was designed, micromolded, and tested, and provides significantly lower heat leak than current state-of-the-art MLI insulation.

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Lightweight, Flexible, Energy-Manageable Polymer Nanocomposites

Applications include solar power panels on aircraft wings or building roofs, and in hybrid car engines. Langley Research Center, Hampton, Virginia Solar energy has attracted keen attention because it is a unique, clean, and sustainable energy resource. It is also widely utilized as a power source in space exploration. A lightweight, durable, deployable, and highly efficient all polymer-based solar power panel was developed comprising a highly efficient thermoelectric conducting polymer composite layer and highly efficient solar absorbance/passive cooling coatings for maximizing efficiency of the power conversion.

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Nanocomposites for Radiation Shielding

Langley Research Center, Hampton, Virginia Currently, lead and lead-based materials are used to fabricate shields not only for X-rays, but also for other types of radiation. With the growing environmental concern about the toxicity of lead, and the high costs associated with transporting heavy lead-based shields in spacecraft, alternatives are needed for fabricating X-ray shields that are less toxic and lighter.

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Advanced Protective Coatings for Graphite Substrates

This innovation enables application of graphite components in a hydrogen environment at very high temperatures. John H. Glenn Research Center, Cleveland, Ohio The purpose of this innovation is to develop advanced multilayered coating architectures to protect graphite substrates from hot hydrogen attack. The concept consists of coating the graphite substrate with metallic and non-metallic layers consisting of ZrC; Nb, Mo, and/or Nb-Mo alloy; and/or Mo2C.

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Regenerable Trace-Contaminant Sorbent for the Primary Life Support System (PLSS)

This technology has applications in air-revitalization systems on spacecraft, submarines, automobiles, and commercial aircraft. Lyndon B. Johnson Space Center, Houston, Texas The NASA objective of expanding the human experience into the far reaches of space requires the development of regenerable life support systems. This work addresses the development of a regenerable air-revitalization system for trace-contaminant (TC) removal for the spacesuit used in extravehicular activities (EVAs). Currently, a bed of granular activated carbon is used for TC control. The carbon is impregnated with phosphoric acid to enhance ammonia sorption, but this also makes regeneration difficult, if not impossible. Temperatures as high as 200 °C have been shown to be required for only partial desorption of ammonia on time scales of 18,140 hours. Neither these elevated temperatures nor the long time needed for sorbent regeneration are acceptable. Thus, the activated carbon has been treated as an expendable resource, and the sorbent bed has been oversized in order to last throughout the entire mission.

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