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Results for “PROPYLENE”

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 163 records · Page 9
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Co-solvents with high coulombic efficiency in propylene carbonate based electrolytes

A homologous series of cyclic carbonate or propylene carbonate (PC) analog solvents with increasing length of linear alkyl substitutes were synthesized and used as co-solvents with PC for graphite based lithium ion half cells. A graphite anode reaches a capacity around 310 mAh/g in PC and its analog co-solvents with 99.95% Coulombic efficiency. Cyclic carbonate co-solvents with longer alkyl chains are able to prevent exfoliation of graphite when used as co-solvents with PC. The cyclic carbonate co-solvents of PC compete for solvation of Li ion with PC solvent, delaying PC co-intercalation. Reduction products of PC on graphite surfaces via single-electron path form a stable Solid Electrolyte Interphase (SEI), which allows the reversible cycling of graphite.

25 ENERGY STORAGE↗
DOE OSTI2018

Insight into Thermal Aging of Jacket-bonded Ethylene-propylene Rubber Cable Insulation

Electrical cables are integral to nuclear power plant operation and control during power generation, during planned outages, and during design basis events. Polymeric insulation and jacketing used in cable construction does age over time as a function of environmental stresses including heat, moisture, and radiation. Degradation of polymer mechanical properties can lead to breaks in the insulation and consequent electrical shorting. In this work we consider the thermal aging behavior of one of the two most common insulation polymer classes in nuclear power plants, ethylene-propylene rubber (EPR), both as an independent material and within a cable in which the EPR is bonded to a chlorinated polyethylene (CPE) jacket. Understanding the changes in these two materials with aging, both independently and in concert, will allow the establishment of aging lifetime curves and enable the development of effective non-destructive methods for tracking the condition of installed cables composed of similar material systems. Additional and more effective methods for monitoring the condition of installed cables are needed as a technical basis for continued safe use of aging cables in long term operation and to minimize operating costs for cable aging management through better informed retain/repair/replace decisions.

Light Water Reactors, electrical cables, aging, EP↗
DOE OSTI2012

Microwave Enhanced Direct Cracking of Hydrocarbon Feedstock for Energy Efficient Production of Ethylene and Propylene

This project demonstrated microwave cracking of ethane with good product conversion and ethylene selectivity, with a short residence time (~0.001 sec). The laboratory scale equipment was designed and built, along with concept designs for larger scale implementation. The system was operated below atmospheric pressures, in the range of 15-55 torr, with argon as a carrier gas. The measured products included hydrogen, methane, acetylene, and ethylene. The results followed similar trends to those predicted by the modeling software SPYRO®, with the exception that the microwave appeared to produce slightly lower amounts of ethylene and methane, although enhanced analytical analysis should reduce the difference. Continued testing will be required to verify these results and quantify the energy consumption of microwave vs. conventional. The microwave cracking process is an attractive option due to the possibility of selectively heating the reaction volume rather than the reactor walls, which may allow novel reactor designs that result in more efficient production of ethylene. Supplemental studies are needed to continue the laboratory testing and refine processing parameters.

02 PETROLEUM↗
DOE OSTI2012

Banded Spherulitic Morphology in Blends of Poly(propylene fumarate) and Poly( -caprolactone) and Interaction with MC3T3-E1 Cells

The thermal properties, morphological development, crystallization behavior, and miscibility of semicrystalline PCL and its 25, 50, and 75 wt% blends with amorphous PPF in spin-coated thin films crystallized at various crystallization temperatures (T{sub c}) from 25 to 52 C are investigated. The surface roughness of PPF/PCL ({phi}{sub PCL} = 75%) films increases with increasing T{sub c} and consequently the adsorption of serum proteins is also increased. No significant variance is found in surface hydrophilicity or in mouse MC3T3-E1 cell attachment, spreading, and proliferation on PPF/PCL ({phi}{sub PCL} = 75%) films crystallized isothermally at 25, 37, and 45 C, because of low ridge height, nonuniformity in structures, and PPF surface segregation

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2018

Poly(propylene)/carbon composite thin films obtained by pulsed electron‐beam deposition

For the first time pulsed electron beam deposition (PED) was used to deposit thin films composed of polymer‐carbon composite material. The targets were polypropylene‐carbon (PP/C) composites, with different carbon fillers: carbon black, nanotubes, or graphene. It was confirmed that coatings with composite structure were obtained – the PED method enables complex structures, including nanotubes, to be ablated whole from the target, transported toward substrate, and incorporated into the polymer matrix. These breakthrough results can contribute significantly to improved understanding of the mechanism of electron beam ablation of polymer and composite materials, and open up new possibilities for the deposition of complex composite thin films for use in, for example, advanced sensor applications.

Jędrzejewski, Roman↗