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NASA NTRS2003

Molecular and Enantiomeric Analysis of Organic Compounds in Carbonaceous Meteorites

Carbonaceous meteorites are relatively enriched in carbon. Much of this carbon is in the form of soluble organic compounds. The Murchison and Murray meteorites are the best-characterized carbonaceous meteorites with respect to organic chemistry. Their content of organic compounds has led to an initial understanding of early solar system organic chemistry as well as what compounds may have played a role in the origin of life (Cronin and Chang, 1993). Reported compounds include: amino acids, amides, carboxylic acids, sulfonic acids, and polyols. This talk will focus on the molecular and enantiomeric analysis of individual meteoritic compounds: polyol acids; and a newly identified class of meteorite compounds, keto acids, i.e., acetoacetic acid, levulinic acid, etc. Keto acids (including pyruvic) are critically important in all contemporary organisms. They are key intermediates in metabolism and processes such as the citric acid cycle. Using gas chromatography-mass spectrometry we identified individual meteoritic keto acids after derivatization to one or more of the following forms: isopropyl ester (ISP), trimethyIsiIy1 (TMS), tert-butyldimethylsilyl (BDMS). Ongoing analyses will determine if, in addition to certain amino acids from Murchison (Cronin and Pizzarello, 1997), other potentially important prebiotic compounds also contain enantiomeric excesses, i.e., excesses that could have contributed to the current homochirality of life.

Cooper, George↗

NASA NTRS2004

Enantiomeric and Isotopic Analysis of Organic Compounds in Carbonaceous Meteorites

Carbonaceous meteorites are relatively enriched in soluble organic compounds. The Murchison and Murray meteorites contain numerous compounds of interest in the study of early solar system organic chemistry and organic compounds of potential importance for the origin of life. These include: amino acids, amides, carboxylic acids, and polyols. This talk will focus on the enantiomeric and isotopic analysis of individual meteoritic compounds - primarily polyol acids. The analyses will determine if, in addition to certain amino acids from Murchison, another potentially important class of prebiotic compounds also contains enantiomeric excesses, i.e., excesses that could have contributed to the current homochirality of life. Preliminary enantiomeric and isotopic (C- 13) measurements of Murchison glyceric acid show that it is indeed extraterrestrial. C-13 and D isotope analysis of meteoritic sugar alcohols (glycerol, threitol, ribitol, etc.) has shown that they are also indigenous to the meteorite.

Cooper, George↗

NASA NTRS1995

Foam, Foam-resin composite and method of making a foam-resin composite

This invention relates to a foam, a foam-resin composite and a method of making foam-resin composites. The foam set forth in this invention comprises a urethane modified polyisocyanurate derived from an aromatic amino polyol and a polyether polyol. In addition to the polyisocyanurate foam, the composite of this invention further contains a resin layer, wherein the resin may be epoxy, bismaleimide, or phenolic resin. Such resins generally require cure or post-cure temperatures of at least 350.degree. F.

Cranston, John A.↗

NASA NTRS2012

Chemical Kinetics of the TPS and Base Bleeding During Flight Test

The present research deals with thermal degradation of polyurethane foam (PUF) during flight test. Model of thermal decomposition was developed that accounts for polyurethane kinetics parameters extracted from thermogravimetric analyses and radial heat losses to the surrounding environment. The model predicts mass loss of foam, the temperature and kinetic of release of the exhaust gases and char as function of heat and radiation loads. When PUF is heated, urethane bond break into polyol and isocyanate. In the first stage, isocyanate pyrolyses and oxidizes. As a result, the thermo-char and oil droplets (yellow smoke) are released. In the second decomposition stage, pyrolysis and oxidization of liquid polyol occur. Next, the kinetics of chemical compound release and the information about the reactions occurring in the base area are coupled to the CFD simulations of the base flow in a single first stage motor vertically stacked vehicle configuration. The CFD simulations are performed to estimate the contribution of the hot out-gassing, chemical reactions, and char oxidation to the temperature rise of the base flow. The results of simulations are compared with the flight test data.

Osipov, Viatcheslav↗

DOE OSTI2021

Polymer compositions and methods

The present invention encompasses polyurethane compositions comprising aliphatic polycarbonate chains. In one aspect, the present invention encompasses polyurethane foams, thermoplastics and elastomers derived from aliphatic polycarbonate polyols and polyisocyanates wherein the polyol chains contain a primary repeating unit having a structure: In another aspect, the invention provides articles comprising the inventive foam and elastomer compositions as well as methods of making such compositions.

Allen, Scott D.↗

DOE OSTI2023

Transfer hydrogenation of heavy hydrocarbons with hydrogen-donor solvents

Processes for converting the coal-derived heavy-oil fraction of syncrude to polyols are described. The processes involve mixing a feed stream comprising the coal-derived heavy-oil fraction with an alcohol and aqueous sulfuric acid, heating the mixture, reacting the coal-derived heavy-oil fraction with ozone, and reacting the ozonated heavy-oil fraction with glycerin to form the polyol. In some cases, the ozonated heavy-oil fraction can be neutralized before reacting the ozonated heavy-oil fraction with the glycerin.

Chauhan, Satya P.↗

DOE OSTI2020

Mechanical Properties of Permanent Foaming Fixatives for Deactivation and Decommissioning Activities

DOE-EM have identified an operational requirement for a fixative that can immobilize and/or encapsulate residual contamination in 3D void volumes (pipes, gloveboxes, waste containers, etc.) during D and D activities. Failure to safely and effectively immobilize residual contamination can: Put workers at risk, Contaminate the public and environment, Drive up operational costs. Commercial-off-the-shelf (COTS) polyurethane (PU) foams is one possible solution and is currently being investigated in collaboration with Savannah River National Lab (SRNL). Mechanical property testing will dictate how well PU foams can withstand physical stressors outlined in safety documents while immobilizing residual contamination. Results can provide a performance criteria for Section 5 of ASTM E3191: Standard Specification for Permanent Foaming Fixatives Used to Mitigate Spread of Radioactive Contamination. Polyurethanes consists of repeating units of urethanes which are produced from an exothermic reaction between a polyol (an alcohol with two or more hydroxyl groups in a molecule) and an isocyanate [2]. PUs consists of 3D cells that are formed by a blowing agent which is normally water. Water interacting with the isocyanate creates carbon dioxide and urea which contributes to cells' growth and expansion. The cross-linking between the polyol and isocyanate solidify the cell faces and walls. Micro scale properties that can influence mechanical properties include: Relative density (ratio between density of cellular material and density of the solid of which the cell walls are made of). Cells connectivity between edges and faces, and number of cells contact neighbors [3]. Whether a foam is open-celled or closed-celled. Closed-celled foams have a thin membrane that encloses each cell which can contribute to the stiffness of the foam. Incorporating fillers in the PU matrix like carbon-based nanoparticles in the form of expandable graphite (EG) can increase the thermal and mechanical performance [4]. When exposed to heat, EG produces a char layer that prevents heat and oxygen transfer which is known as intumescing. Mechanical performance is dependent on amount of EG loading since the cell sizes are linearly dependent on it. Overall, the rigid foams (I-R2) proved superior. SEM Analysis: I-R2 had the most consistent spherical sizes (average cell diameter: 489 μm), which enhance the relative density the most [5]. Tensile Testing Results: I-R2 experienced the largest breaking load (103.65 lbf) and stress (289.42 psi). I-R2 also had a higher Young's Modulus compared to R1 (2.99 ksi to 2.09 ksi). Compression Testing Results: I-R2 had the highest stress at 80% deflection (360.67 psi), load (1387.48 lbf) and modulus (3.92 ksi)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2024

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.↗

DOE OSTI2024

Tailoring High Hardness and Rigidity in Biodegradable Thermoplastic Polyurethanes

In response to escalating environmental concerns, there is a pressing demand for materials capable of delivering both sustainability and robust mechanical properties, thereby substituting nonrenewable counterparts in various applications. This study presents a comprehensive investigation into the synthesis and characterization of biobased aliphatic thermoplastic polyurethanes (TPUs) that exhibit impressive mechanical properties, including tensile strength in the range of 48–41 MPa and flexural modulus up to 2.2 GPa. These biodegradable TPUs displayed high shore A and D hardness between 95 and 98 and 51–42, respectively, and thus can be categorized as “extra hard” plastics according to the durometer scale for PUs. Herein, we have prepared a series of four 100% biobased polyester polyols from biobased diacid and chain-extender as precursors with molecular weights varying from 500 to 1400 g/mol. The corresponding TPUs that were prepared by using an aliphatic diisocyanate were evaluated for their thermal stability, microphase separation, mechanical properties, and biodegradation. By leveraging renewable feedstocks, these TPUs offer a sustainable alternative to petroleum-derived materials, with their mechanical performance meeting conventional benchmarks. Furthermore, postcomposting analysis revealed significant surface degradation, affirming their biodegradability and environmental compatibility.

36 MATERIALS SCIENCE↗

DOE OSTI2022

Atomistic insights into the heat conductance across the interfaces between erythritol and different metals: A non-equilibrium molecular dynamics study

The heat conductance across the interface between a phase change material (PCM) and the metal shell is important for thermal design of latent heat storage systems. Non-equilibrium molecular dynamics simulations were carried out in this work to unravel, at the atomistic level, the interfacial heat conductance mechanisms between erythritol (the most promising medium-temperature polyol PCM) and two different metals (i.e., copper and aluminum). The interfacial contact ratio was introduced as a parameter to represent different contact conditions at the interfaces, for example, different surface roughness levels of the metals. It was found that with the increase of interfacial contact ratio, the temperature difference between the erythritol/metal interfaces decreases, whereas the interfacial heat transfer coefficient increases gradually. At the perfect contact condition, i.e., the interfacial contact ratio reaches 100%, the interfacial heat transfer coefficients across the erythritol/Cu and erythritol/Al interfaces were predicted to be 398 ± 26 MW/m 2 K and 544 ± 11 MW/m 2 K, respectively. The interfacial heat conductance of erythritol/Al is better than that of erythritol/Cu. The mismatch of atomic spectral density across the interfaces between erythritol and the two metals was analyzed and distinguished. These results could guide the selection of packaging materials and the thermal design of erythritol-based latent heat storage systems.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2023

Efficient separation and coprecipitation for simplified cathode recycling

Hydrometallurgical recycling of spent lithium-ion batteries is among the most promising recovery approaches. The current hydrometallurgical method for battery recycling faces challenges such as complex separation and precipitation processes, and environmental concerns from the use of caustic inorganic acid and hazardous hydrogen peroxide. Our proposed modified method, namely polyol-metallurgy, uses citric acid in ethylene glycol as dual-function green solution to overcome these obstacles. This bifunctional solution leaches valuable metal ions from cathode materials (e.g., LiCoO 2 ), and then acts as chelating agents to selectively precipitate cobalt through an esterification reaction, without the need for additional precipitation agents. The leaching efficiency of cobalt and lithium reaches 99.55% and 97.65%, respectively, and more than 96% of cobalt could be directly self-precipitated and recovered. Further, the unique characteristics of the dual-function solution also avoids impurities from Al foils and PVDF/carbon black films, enabling the simple separation process. Therefore, the process can be completed in one-pot system with efficient leaching, separation and coprecipitation, making it more efficient and feasible for operation than existing alternatives.

25 ENERGY STORAGE↗

DOE OSTI2020

Cobalt Metal–Cobalt Carbide Composite Microspheres for Water Reduction Electrocatalysis

Microspheres of cobalt metal–cobalt carbide (Co–Co x C, Co x C: Co 2 C and Co 3 C) composite with carbon shells were prepared via an OH – - and Cl – -assisted polyol method and explored for electrocatalytic activity and stability for the hydrogen evolution reaction (HER) in acidic media. From our transmission electron microscopy observations, the outermost surfaces of the as-prepared Co–Co x C composites were primarily covered with Co 2 C crystallites. Our best performing electrocatalyst exhibited superior HER activity with an overpotential of 78 mV to reach a current density of -10 mA·cm –2 , a Tafel slope of 87.8 mV·dec –1 , and 1 h of electrode durability. We show that this excellent HER performance is primarily due to the superior intrinsic activity of Co 2 C, as well as the high electrical conductivity resulting from the inclusion of cobalt metal and the presence of graphitic carbon shells in and on the composite, respectively. Using both computational and experimental approaches, we determine here that the carbon-rich cobalt carbide (Co 2 C) phase is more favorable for the HER than the carbon-poor phase (Co 3 C).

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2021

Valorisation of technical lignin in rigid polyurethane foam: A critical evaluation on trends, guidelines and future perspectives

Lignin is one of the most abundant aromatic natural polymers. Produced as a by-product from the biomass refinery industries, lignin remains largely underutilised in high-value industrial applications. The incorporation of lignin in rigid polyurethane foam (RPUF) has been the focus of much research, due to its potential to replace fossil fuel-based components of RPUF. However, the overall sustainability of RPUF depends on numerous factors including processability, cost-effectiveness, and retention of performance throughout the service life. To date, the incorporation of lignin has been explored either as filler particles (through direct incorporation) or as a blendable liquid polyol introduced after chemical modifications (such as oxyalkylation, functionalisation, or depolymerisation). However, the production of lignin incorporated foam with high performance through cost-effective processing is still an ongoing challenge. Herein, this review critically appraises the progress on the effective incorporation of lignin in RPUF. Firstly, this review briefly covers the essential raw materials, formulation, important properties, and sustainability aspects of RPUF for industrial applications. Secondly, it provides insights on the key parameters of lignin of relevance to incorporation into RPUF. Thirdly, it benchmarks the reported studies on incorporation of lignin in RPUF systems by evaluating their important properties and proposes potential strategies for addressing the key challenges in the incorporation of lignin in RPUF. By bridging the gaps that exist in the literature on the utilisation of lignin in RPUF this account will serve as a resource for both beginners and professionals in the polyurethane and biorefinery industries towards the successful development of lignin incorporated RPUF for industrial applications

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2020

Sub‐5 nm Intermetallic Nanoparticles Confined in Mesoporous Silica Wells for Selective Hydrogenation of Acetylene to Ethylene

Abstract We report the synthesis and catalytic application of intermetallic PtSn nanoparticles confined in MSWs (Mesoporous Silica Wells) in the semi‐hydrogenation of acetylene. Platinum nanoparticles with a size of 2.9 nm supported on amine‐functionalized ∼180 nm silica spheres were enmeshed in a mesoporous silica shell. After the addition of tin via a polyol synthesis method, we obtained the final PtSn x @MSW (x=0.30, 0.50, 0.70, 1.0 and 2.0). Owing to the mesoporous encapsulation the sub‐5 nm bimetallic particles are shown to be monodisperse and well protected against aggregation on the silica sphere even under high‐temperature treatment conditions. In the gas phase semi‐hydrogenation of acetylene, the PtSn@MSW with Sn/Pt molar ratios equal to or greater than one displayed higher selectivity to ethylene. Meanwhile, increasing Sn content decreases acetylene conversion. The intermetallic PtSn@MSW catalysts also displayed long‐term stability and regenerability due to the confined environment provided by MSW.

Maligal‐Ganesh, Raghu V.↗

DOE OSTI2024

Structure Development in Cross-Linked, Soybean Oil-based Waterborne Polyurethanes

Development of waterborne polyurethanes (WPU) using bio-based sources represents a step towards sustainable materials science and industry. We synthesized bio-based cationic water-dispersed crosslinked polyurethanes from high oleic soybean oil (HOSO) polyol, isophorone diisocyanate, and methyldiethanol amine, with varying ionic group contents after neutralization with acetic acid. Our primary objective was to analyze how crosslinking affects the dispersion process and film properties in multifunctional systems. The synthesis-structure-property relationship is elucidated through comprehensive analyses of the products at different stages of the synthesis. The dispersion of the WPU particles in water must occur prior to gelation during the final preparation, leading to incomplete conversion and the formation of imperfect networks. Insight into the synthesis process and polymer structure was gained by simulating polymer network parameters. Morphological analyses using synchrotron-based X-ray scattering and atomic force microscopy revealed a hierarchical structure within the WPU films. Importantly, all the films prepared in this study, without using coalescence agents, have low water absorption and high water contact angles, demonstrating their potential for textile and leather coatings and other applications.

bio-based polymers↗

DOE OSTI2023

Hemp fiber reinforced dual dynamic network vitrimer biocomposites with direct incorporation of amino silane

Natural fiber composites are inexpensive and renewable alternatives to traditional fiber reinforced polymers (FRPs). However, existing natural fiber composites primarily rely on petrochemical based thermosetting matrices, which are difficult to recycle due to their stable crosslinked network structures. To address this challenge, it is desirable to develop natural fiber composites with inherently recyclable biobased matrices. In this study, we developed a dual dynamic network vitrimer matrix from hempseed oil and limonene derivatives and demonstrated its application in hemp fiber reinforced composites. To improve the weak interface between hemp fiber and the polymer matrix, a common challenge in the realm of natural fiber composites, we directly incorporated amino silane into the vitrimer matrix. The amino silane participated in the polymer network, increasing the crosslink density and toughening the matrix, as evidenced by a significantly improved impact strength from 3.5 kJ/m 2 to 10.3 kJ/m 2 . Moreover, the incorporation of amino silane resulted in a lower water absorption by 11% in 7-day soaking for the composites, demonstrating improved fiber/matrix interfacial interaction. Furthermore, our biobased vitrimer matrix exhibits both imine and hydroxy-ester dynamic bonds, which enable the recycling of the biocomposite through a mild and cost-effective aminolysis process (100°C, 3h, ambient pressure). The decomposed polymer matrix was successfully reused as a polyol for polyurethane adhesives, and the surface morphology of recovered hemp fibers was analyzed and compared with that of the original fibers. Furthermore, these findings will help broaden the use of vitrimers for practical natural fiber composite applications, raise awareness of the problem of recycling natural fiber composite waste, and shed light on the interfacial challenge of natural fiber reinforced vitrimer composites.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2026

A Catabolic Powerhouse for Biorefineries: Characterization and Engineering Erwinia spp. Strain LJJL01 to Produce Bioproducts

Nonmodel microbial hosts can efficiently biotransform unconventional organic feedstocks into advanced bioproducts, leveraging their superior metabolic capabilities and resilience to process-relevant physicochemical conditions. In this study, we domesticated Erwinia spp. strain. LJJL01 (Er LJJL01) as a potent microbial chassis to advance the emerging biorefinery strategy for the valorization of lignin-rich biomass and plastic, thereby enabling the circular economy. The strain exhibits remarkable chemical tolerance and can biofunnel various substrates, including sugars, acids, polyols, and aromatics, in minimal salt media to produce native fine chemicals such as acetoin, 2,3-butanediol, and lactic acid. As a proof of concept, engineering this strain with advanced genetic tools enables the production of tailored high-value chemicals, such as cis,cis-muconate from plastic-derived terephthalate and polyhydroxybutyrate from lignocellulosic hydrolysate. We established Er LJJL01 as a potent microbial chassis for the green synthesis of bioproducts from unconventional organic feedstocks.

09 BIOMASS FUELS↗

DOE OSTI2024

Scale-Up of a Two-Stage Cu-Catalyzed Alkaline-Oxidative Pretreatment of Hybrid Poplar

A two-stage alkaline-oxidative pretreatment of hybrid poplar was investigated at scale (20 L reactor volume) with the goals of understanding how reaction conditions as well as interstage mechanical refining impact downstream process responses. The pretreatment comprises a first stage of alkaline delignification (alkaline pre-extraction) followed by a second delignification stage employing Cu-catalyzed alkaline hydrogen peroxide with supplemental O 2 (O 2 -enhanced Cu-AHP). Increasing pre-extraction severity (i.e., temperature and alkali loading) and pre-treatment oxidation (increasing H 2 O 2 loading) were found to increase mass and lignin solubilization in each stage. Lignin recovered from the first stage was subjected to oxidative depolymerization and led to aromatic monomer yields as high as 23.0% by mass. As a result, lignins recovered from the second stage Cu-AHP pretreatment liquors were shown to exhibit aliphatic hydroxyl contents more than six-fold higher than for a typical hardwood kraft lignin, indicating these lignins could serve as a biobased polyol for a range of polyurethane applications.

09 BIOMASS FUELS↗