An exploratory study of a new class of stepladder and ladder polymers - polyimidazopyrrolones
Synthesis of aromatic heterocyclic polymers /polyimidazopyrrolones/ - thermal and radiolytic stability
THERMOSTABILITY↗
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Results for “AZO COMPOUND”
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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2-Oxazolidones.
Classification of 2-oxazolidones, examining preparation, physical chemistry, properties and polymerized derivatives
ORGANIC COMPOUND↗
Polyimidazopyrrolones - A new route to ladder polymers.
Synthesis of polyimidazopyrrolones, using previous macromolecular synthesis of ladder segments of aromatic-heterocyclic polymers
AROMATIC COMPOUND↗
The use of azo arsine III as a color comparing reagent for scandium
Azo arsine as color comparison reagent for scandium determination
AZO COMPOUND↗
Chromophores from photolyzed ammonia reacting with acetylene: Application to Jupiters Great Red Spot
The high altitude of Jupiter's Great Red Spot (GRS) may enhance the upward flux of gaseous ammonia (NH3 ) into the high troposphere, where NH3 molecules can be photodissociated and initiate a chain of chemical reactions with downwelling acetylene molecules (C2H2 ). These reactions, experimentally studied earlier by (Ferris and Ishikawa [1987] Nature 326, 777-778) and (Ferris and Ishikawa [1988] J. Amer. Chem. Soc. 110, 4306-4312), produce chromophores that absorb in the visible and ultraviolet regions. In this work we photolyzed mixtures of NH3 and C2H2 using ultraviolet radiation with a wavelength of 214 nm and measured the spectral transmission of the deposited films in the visible region (400-740 nm). From these transmission data we estimated the imaginary indices of refraction. Assuming that ammonia grains at the top of the GRS clouds are coated with this material, we performed layered sphere and radiative transfer calculations to predict GRS reflection spectra. Comparison of those results with observed and previously unreported Cassini visible spectra and with true-color images of the GRS show that the unknown GRS chromophore is spectrally consistent with the coupled NH3-C2H2 photochemical products produced in our laboratory experiments. Using high-resolution mass spectrometry and infrared spectroscopy we infer that the chromophore-containing residue is composed of aliphatic azine, azo, and diazo compounds.
Jupiter↗
Synthesizing, Compounding, and Characterizing a Heat Labile Polyurethane Foam
ABSTRACT A need exists for a packaging foam material that can be converted from solid to gaseous degradation products at reasonably low energy levels or temperatures, such as 100O C. This paper will primarily discuss the approaches currently being used to synthesize and characterize such a material. These approaches include the incorporation of novel polyols such as azo containing diols, polycarbonate diols, and polypropylene carbonate polyols into polyurethane foams. Characterization methods include NMR, FTIR, TGA, finite element analysis, impact strength, and others. This project will be funded for a duration of three years. Year 1 focused on developing the proposed test methods and producing an initial rigid polyurethane foam. Year 2 focuses on refining the materials and test methods. If appropriate, design of experiment (doe) techniques will be used to optimize components, component levels, density and other variables to attain required final material properties (TGA weight loss, impact strength, etc.). Year 3 focuses on scaling up to larger engineering quantities. The application for this material is in load securement for transportation of low level radioactive waste materials within the US Department of Energy (DOE) complex. Foam in place process equipment and operators will be shielded using this novel method over current practice. Current practice can involve time consuming methods of load securement in low level radiation environments. This new technique would eliminate exposure time securing the load and greatly improve the As Low As Reasonably Attainable (ALARA) conditions. The objective is to progress to higher Technical Readiness Levels (TRL) and larger pilot scale quantities. This paper discusses methodologies and presents current results to date.
Kranjc, Mark D.↗