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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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Identification of primary mechanisms in solar radiation induced damage to optical properties of zinc oxide-type semiconductor pigments
Mechanisms of light scattering in concentrated pigment films and experiments in optical properties of silver halide particle arrays
Light scattering behavior of pigmented coatings
Monte Carlo simulation techniques applied to light scattering in highly reflective pigmented coatings
Monte Carlo treatment to find light scattering parameters of metal filled, reflecting pigmented coatings
Monte Carlo method applied to pigment particle clusters, and relevance of Mie scattering function to reflected light
Powdered metal oxide pigments by nucleation for temperature control coatings
Synthesis of mediators of sympathetic nervous system and pigmentation in ontogenesis of vertebrates
Light scattering in highly reflecting pigmented coatings - silver bromide and particle suspensions and paint films
Pyrolysis offers a relatively green and economical method to convert waste plastics into valuable chemicals and fuels without the need for harmful solvents, toxic chemicals, or costly high-pressure reactors. Despite its popularity among chemical upcycling technologies, industrial adoption suffers from feedstock heterogeneity, low-quality products, and catalyst deactivation. Most plastics in our daily lives are formulated with functional additives, fillers, and colorants. These additives remaining in end-of-life waste streams increase feedstock heterogeneity, creating a challenging issue in recycling plastics. Still, the potential impacts of additives on the chemical upcycling of plastics have been poorly understood. In this study, polyethylene compounded with a range of widely used additives (antioxidants, stabilizers, pigments, fillers, slip agents, and flame retardants) was subjected to both thermal pyrolysis and catalytic pyrolysis in different catalyst-to-feedstock contact modes. It showed that many inorganic additives, such as talc, kaolin, CaCO 3 , TiO 2 , carbon black, and zinc stearate, facilitated polymer decomposition during pyrolysis, increasing light hydrocarbons while also promoting aromatic and carbon residue formation. Conversely, antioxidants and stabilizers inhibited depolymerization, favoring heavier hydrocarbons. During catalytic pyrolysis with HZSM-5 zeolite, additives strongly enhanced aromatic and catalytic coke formation, especially when there was direct contact between plastics and catalysts. Although certain additives seem beneficial in the short term by promoting polymer cracking and improving the selectivity of aromatics, the transport of the additives and their degradation products and increased carbon coking can contaminate products, deactivate or modify catalysts, and foul reactors. These findings address a critical knowledge gap in effectively converting waste plastics via a greener route.
The solvent-targeted recovery and precipitation (STRAP) process separates and recovers the constituent resins in multilayer plastic packaging films by selective polymer dissolution. In this work, the cause of coloring in the STRAP-recycled polyethylene (PE) resins from postindustrial printed films was identified as decomposed diarylide pigments. Two different approaches are needed to completely remove the dissolved colorants during the STRAP process including (i) adding an activated carbon (AC) adsorbent to the solvent after polymer dissolution and (ii) proper mechanical filtration of the polymer-solvent cake to remove as much solvent from the cake as possible. Colorless recycled PE can be produced by a combination of the proposed approaches (choosing the proper solvent, adding an AC adsorbent, and doing proper mechanical filtration) with minimal accumulation of colorants in the recycled STRAP solvents. This study demonstrated that high-quality STRAP low-density PE can be obtained from printed plastic films, enhancing the potential circularity of these packaging materials.
Light scattering in highly reflecting pigmented coatings - silver halide crystals
Coating pigment composed of zinc oxide and potassium silicate resists the effects of thermal shock and long exposure to direct sunlight.
Application of light scattering theories to highly pigmented coatings
Solar radiation induced damage to optical property of zinc oxide semiconducting pigment coating
Difference spectra of glucose cultures of Chlorella vulgaris beyernick indicate increased pigmentation in white light and monochromatic light over dark controls
Degradation model of solar radiation damage to optical properties of zinc oxide pigments used for spacecraft thermal control coatings
Mechanisms of solar radiation damage to optical properties in zinc oxide pigments in visible and infrared regions