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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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At least 199 records · Page 11
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Dynamic Impact Testing of Rigid Polyurethane Foam

At the request of SRNL/Packaging Technology and Pressurized Systems, a Dynamic Impact Tester was developed by SRNL/Materials Evaluation that provides ease of use and the ability to test rigid polyurethane foam of various densities and sizes. In this initial testing comparisons were made between the properties of a currently approved foam product (General Plastics LAST-A-FOAM® FR3724) to those of an alternative supplier’s product (Paragon Dow Beta Foam). The basis for how the equipment and test methodology were developed is discussed. Overall, the testing showed very good correlation of energy absorption (ft-lb/in 3 ) versus %Crush data between General Plastics LAST-A-FOAM® FR3724 literature data and Paragon Dow Beta Foam on the Dynamic Impact Tester developed.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Additive Manufacturing of Polyurethane Materials

ORNL worked with The DOW Chemical Company to validate the feasibility of 3D printing DOW’s polyurethane (PU) materials using ORNL’s equipment and know-how. This led to the development of the first directly-3D-printable PU material.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Modeling Heat Transfer and Pressurization of Polymeric Methylene Diisocyanate (PMDI) Polyurethane Foam in a Sealed Container

Polymer foam encapsulants provide mechanical, electrical, and thermal isolation in engineered systems. It can be advantageous to surround objects of interest, such as electronics, with foams in a hermetically sealed container to protect the electronics from hostile environments, such as a crash that produces a fire. However, in fire environments, gas pressure from thermal decomposition of foams can cause mechanical failure of the sealed system. In this work, a detailed study of thermally decomposing polymeric methylene diisocyanate (PMDI)-polyether-polyol based polyurethane foam in a sealed container is presented. Both experimental and computational work is discussed. Three models of increasing physics fidelity are presented: No Flow, Porous Media, and Porous Media with VLE. Each model us described in detail, compared to experiment, and uncertainty quantification is performed. While the Porous Media with VLE model matches has the best agreement with experiment, it also requires the most computational resources.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Characterization of Radiation Hardened Polyurethane Foams for DOE Decontamination and Decommissioning (D&D) Operations

The use of polyurethane foams has been under investigation to see if they can be used in DOE decontamination and decommissioning (D&D) operations, specifically to fixate and shield any remaining contamination that is left in any voided structure such as a glovebox. To fix this problem, SRNL attempted to characterize different commercial epoxy foams to evaluate their foam characteristics in different environments, temperature profiles, viscoelastic behavior, shielding capability, and any changes to these characteristics when different weight percent additives were included in the foam matrix. The use of these foams has not been realized yet because of excessive heat generation and flammability concerns during thecuring process.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Room Temperature Quasi-static Characterization and Constitutive Model Parametrization of Flexible Polyurethane Foams of Different Densities Loaded in Different Orientations

This report describes the efforts to characterize and model General Plastics TF6070 and EF4000 flexible polyurethane foams under room temperature, large deformation quasi-static cyclic mechanical loading conditions. Densities from three to fifteen pound per cubic foot (PCF) are examined, which correspond to relative densities of approximately 4 to 20%. These foams are open cell structured and flexible at room temperature with a glass transition transition less than -30°C, and they fully recover their original shape when unloaded (at room temperature). Uniaxial compression tests were conducted with accompanying lateral image series for Digital Image Correlation (DIC) analysis with the goal of extracting transverse strain responses. Due to difficulties with DIC analysis at large strains, lateral strains were instead extracted for each test via edge tracking. The experimental results exhibit a nonlinear elastic response and anisotropic material behavior (particularly for the lower densities). Some hysteresis is observed that is different between the first and subsequent cycles of deformation indicating both a small degree of permanent damage (reduced stiffness during reloading) and viscoelasticity. These inelastic mechanisms are not considered in the modeling and calibration in this report. This work considers only the rate independent, room temperature foam behavior. Individual foam densities were calibrated for loading in two directions, parallel and perpendicular to the foam bubble rise direction, since the mechanical behavior is different in these two directions. The Flex Foam constitutive model was used for all parameterizations despite the fact that the model is isotropic. A review of the constitutive model is given as well as necessary data reduction procedures to parameterize it for each foam density and orientation are discussed. Finally, two different parameterizations are developed that take the undeformed foam density as an input that span all densities considered. These two parameterized models represent foams loaded in the rise and transverse directions respectively. We summarize the assumptions and limitations of the parameterizations provided in this report to guide analysis choices with them. All parameterizations presented herein have the following traits, room temperature, rate independent, damage-free, and non-dissipative . Isotropy (even if they are representing anisotropic data). Supplied Sierra Solid Mechanics Flex Foam Model Inputs are in units: pounds, inches, Celsius, and seconds

36 MATERIALS SCIENCE↗
DOE OSTI2021

Experimental Study of Mechanical Response of Polyurethane Rubber at Varying Strain Rates for W80-4 System

This report describes an experimental study to determine the mechanical behavior of the polyurethane rubber material that was used in the W80-4 MCC Shock/Breach Phase 1 test series. Compression experiments were conducted on cylindrical specimens over a wide range of loading rates to characterize the material over the range of strain rates that were experienced in the shock/breach testing. Additionally, specimen diameter was varied to determine the effect of confinement on the material response and was found to be significant. This data is used to populate a material model to enable accurate analyses and finite element simulations of the shock/breach test series.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Advanced Algal Biofoundries for the Production of Polyurethane Precursors (CRADA Final Report)

The primary goal of the BEEPs project was to develop a process that could accelerate the development of algae as bioproduction platforms, from initial chemical product concept to an economically viable market supply. Under this program we elected to develop strains of algae that could generate polyurethane precursors, while simultaneously developing basic genetic tools to enable improved algal production systems. This program was specifically designed to incorporate National Laboratories as a means to utilize the expertise and facilities for new bioproduction platforms.

09 BIOMASS FUELS↗
DOE OSTI2024

Development of Radiation and Fire Resistant Polyurethane Foam in Support of Deactivation and Decommissioning [Poster]

FoamBag™ is a two-part polyurethane foam that has been down selected as a possible engineering solution for the decommissioning of radiologically contaminated pipes. Our main objective consists of establishing an internal barrier (plug) to mitigate the release of residual contamination prior to cutting operations and required pipework for deactivation and decommissioning projects. To ensure worker safety, we will also be analyzing hazards associated with the off gasses present during curing.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2025

TDI-Free Polyurethane Encapsulants: Alternatives to EN-7/EN-8

This report documents a cross-site effort to identify and evaluate materials that are suitable replacements for the polyurethanes known as EN-7 and EN-8. EN-7 and EN-8 are commercial formulations that contain free toluene diisocyanate (TDI) and which are used as adhesives and as encapsulants in many weapon applications. TDI is an OSHA-regulated volatile diisocyanate and has been targeted for elimination from future weapons use, prompting the need for a TDI-free replacement material.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Green Biodegradation: Analysis of Potential Polyurethane-degrading Enzymes and Their Secretion in Chlamydomonas reinhardtii

Plastic pollution is a critical global issue, with only 5% of plastics currently recycled. Polyester polyurethane (PU), a widely used plastic, can potentially be broken down using enzymatic biodegradation rather than mechanical processing that generates microplastics. This study focuses on PS5, a potential PU-degrading enzyme with esterase activity, capable of cleaving ester bonds found in PU structures. Researchers investigated the expression and secretion of PS5 in the green microalga Chlamydomonas reinhardtii, a sustainable production platform capable of generating PU precursors such as lipids and diacids while sequestering carbon. Experiments demonstrated that PS5 significantly outperformed commercial lipase in cleaving the FDA substrate, indicating high esterase activity. Algal transformants expressing PS5 also showed halo formation on Impranil®-agar plates, suggesting PU dispersion degradation. These findings highlight C. reinhardtii as a viable chassis for the production and secretion of plastic-degrading enzymes, offering a sustainable route to both upcycle and degrade PU products at the end of their lifecycle.

Diaz, Crisandra Jade↗
DOE OSTI2023

Simple Bioparticle Filtration Device Based on an Ultralow-Fouling Zwitterionic Polyurethane Membrane for Rapid Large-Volume Separation of Plasma and Viruses from Whole Blood

Plasma separation from whole blood is oftent required as an essential first step when performing blood tests with a viral assay. However, developing a point-of-care plasma extraction device with a large output and high virus recovery remains a significant obstacle to the success of on-site viral load tests. Here, we report a portable, easy-to-use, cost-efficient, membrane-filtration-based plasma separation device that enables rapid large-volume plasma extraction from whole blood, designed for point-of-care virus assays. The plasma separation is realized by a low-fouling zwitterionic polyurethane-modified cellulose acetate (PCBU-CA) membrane. The zwitterionic coating on the cellulose acetate membrane can decrease surface protein adsorption by 60% and increase plasma permeation by 46% compared with a pristine membrane. The PCBU-CA membrane, with its ultralow-fouling properties, enables rapid plasma separation. The device can yield a total of 1.33 mL plasma from 10 mL whole blood in 10 min. The extracted plasma is cell-free and exhibits a low hemoglobin level. In addition, our device demonstrated a 57.8% T7 phage recovery in the separated plasma. The results of real-time polymerase chain reaction analysis confirmed that the nucleic acid amplification curve of the plasma extracted by our device is comparable to that obtained by centrifugation. With its high plasma yield and good phage recovery, our plasma separation device provides an excellent replacement for traditional plasma separation protocols for point-of-care virus assays and a broad spectrum of clinical tests.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Bio-Based Polyurethane Materials: Technical, Environmental, and Economic Insights

Polyurethane (PU) is widely used due to its attractive properties, but the shift to a low-carbon economy necessitates alternative, renewable feedstocks for its production. This review examines the synthesis, properties, and sustainability of bio-based PU materials, focusing on renewable resources such as lignin, vegetable oils, and polysaccharides. It discusses recent advances in bio-based polyols, their incorporation into PU formulations, and the use of bio-fillers like chitin and nanocellulose to improve mechanical, thermal, and biocompatibility properties. Despite promising material performance, challenges related to large-scale production, economic feasibility, and recycling technologies are highlighted. The paper also reviews life cycle assessment (LCA) studies, revealing the complex and context-dependent environmental benefits of bio-based PU materials. These studies indicate that while bio-based PU materials generally reduce greenhouse gas emissions and non-renewable energy use, their environmental performance varies depending on feedstock and formulation. The paper identifies key areas for future research, including improving biorefinery processes, optimizing crosslinker performance, and advancing recycling methods to unlock the full environmental and economic potential of bio-based PU in commercial applications.

Jayalath, Piumi↗
NASA NTRS1967

Nonwoven glass fiber mat reinforces polyurethane adhesive

Nonwoven glass fiber mat reinforces the adhesive properties of a polyurethane adhesive that fastens hardware to exterior surfaces of aluminum tanks. The mat is embedded in the uncured adhesive. It ensures good control of the bond line and increases the peel strength.

Roseland, L. M.↗
NASA NTRS1969

Improved primer for bonding polyurethane adhesives to metals

Primer ensures effective bonding integrity of polyurethane adhesives on metal surfaces at temperatures ranging from minus 423 degrees to plus 120 degrees F. It provides greater metal surface protection and bond strengths over this temperature range than could be attained with other adhesive systems.

Constanza, L. J.↗