Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “foams”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Foaming prediction in pure liquids from dimensionless numbers inspired by the theory of fluid behavior for drops

Foaming prediction is critical for selecting materials and designing processes in industries such as bioprocessing and gas processing. Existing models lack the generality needed for a wide range of materials and overlook the foaming behavior in pure liquids. Here, this work presents a novel method for predicting foaming in pure liquids based on their density, surface tension, and viscosity, using Reynolds ( Re ) and Ohnesorge ( Oh ) numbers. A foaming prediction map, leveraging the theory of fluid drop behavior, was developed by plotting these numbers. This map delineates distinct non-foaming and foaming regions, functioning as a binary classifier for foaming predictions. The map was fitted and validated through shake test experiments on 46 liquids, demonstrating reliable predictions, except for a specific region characterized by small Oh and large Re numbers. This region corresponded to relatively low foam stability and high turbulence, making foaming predictions challenging for liquids in this category.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Heat transfer model for moving packed-bed particle-to-sCO 2 heat exchangers integrated with metal foams

Particle-to-supercritical carbon dioxide (sCO 2 ) heat exchangers (HXs) play a vital role in coupling heat transfer fluid (HTF) from high-temperature thermal receivers to power cycle working fluids (WF). Heat transfer enhancement is essential for adopting particle-based moving packed-bed heat exchangers (MPBHXs) in next-generation thermal energy storage (TES) systems, as MPBHXs usually exhibit low particle bed-to-wall heat transfer coefficients. High-porosity metal foams have shown their effectiveness in heat transfer enhancement. Here, this work presents a continuum heat transfer model to demonstrate the heat transfer enhancement in MPBHXs when the particle bed channel is filled with high porosity metal foams compared to open channel MPBHXs. The presence of metal foams increases the effective thermal conductivity in the particle channel and enhances the interstitial heat transfer coefficient between the moving particle bed and the stationary metal foams. The present model considers coupled two-dimensional (2D) heat transfer in the particle channel with metal foams and 1D heat transfer in the sCO 2 channel and the dividing wall. The temperature profiles for the particle bed, metal foam, dividing wall, and sCO 2 stream, as well as the local heat flux profiles between those, are studied in detail for various foam porosities, from which the particle bed-to-wall heat transfer coefficient, overall heat transfer coefficient, and total heat transfer rate for the MPBHX are determined. The effects of major MPBHX design and operating parameters on the particle bed-to-wall heat transfer coefficient and overall heat exchange capacity are thoroughly examined; thus, the MPBHX performance improvement with metal foams is quantified for each case. The present heat transfer model can provide valuable insights into the metal-foam MPBHX design and optimization, scale-up, and operating parameters selection.

42 ENGINEERING↗
DOE OSTI2021

Experimental validation of shock propagation through a foam with engineered macro-pores

The engineered macro-pore foam provides a new way to study thermonuclear burn physics by utilizing capsules containing deuterated (D) foam and filling tritium (T) gas in the engineered macro-pores. The implosion of a thermonuclear capsule filled with an engineered macro-pore foam will be complex due to the interaction of a shock wave with the engineered macro-pores. It is our goal to quantify how substantially complex foam structures affect the shape of shock and bulk shock speed. A cylinder-shape shock tube experiment has been designed and performed at the Omega Laser Facility. In order to examine how a foam structure will affect shock propagation, we performed several tests varying (1) engineered macro-pore size, (2) average foam density, and (3) with/without neopentane (C 5 H 12 ) gas. X-ray radiographic data indicate that shock speed through engineered macro-pore foams depends strongly on average foam density and less on pore size. In this work, experimental shock propagation data helped guide two numerical simulation approaches: (1) a 2D simulation with homogenizing foams rather than explicitly simulating engineered macro-pores and (2) a 2D toroidal-pore approximation adopting a toroidal-tube geometry to model engineered macro-pores.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2021

Simulation studies of the interaction of laser radiation with additively manufactured foams

The interaction of laser radiation with foams of various porosities and low densities has been the subject of several numerical and experimental studies. In all cases, the modeling of low-Z under-dense foams as uniform gases of equivalent average density using standard radiation-hydrodynamics codes has resulted in heat-front velocities that are considerably faster than those observed experimentally. It has been theoretically conjectured that this difference may be attributed to the breakdown of the foam’s morphology, leading to a dynamics of filament expansion where the ion and electron energy partitions are significantly different from those calculated using the uniform gas model. We found that 3D computer simulations employing a disconnected representation of the foam’s microstructure which allowed for the dynamics of foam element heating, expansion, and stagnation largely supported the theoretical picture. Simulations using this model for laser experiments on under-dense 2 mg cc -1 SiO 2 aerogel foams reproduced the experimental data fairly well. We used the validated model in simulations of low-density structured foam-like materials (produced via additive manufacturing) with a variety of morphologies. We found that the log-pile configurations were consistent with the analytical propagation model of Gus’kov et al. Further validation of the model was obtained by simulating experiments performed at the Jupiter Laser Facility using the log-pile and octet-truss foam morphologies. Simulations of the foam-laser interaction using a wave propagation code showed that the microstructure was able to enhance stimulated Brillouin scattering (SBS) by concentrating the light energy into density holes. In turn, this promotes laser filamentation, reducing SBS and bringing the predicted values closer to the experimental data.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2021

High-temperature high-pressure microfluidic system for rapid screening of supercritical CO 2 foaming agents

CO 2 foam helps to increase the viscosity of CO 2 flood fluid and thus improve the process efficiency of the anthropogenic greenhouse gas’s subsurface utilization and sequestration. Successful CO 2 foam formation mandates the development of high-performance chemicals at close to reservoir conditions, which in turn requires extensive laboratory tests and evaluations. This work demonstrates the utilization of a microfluidic reservoir analogue for rapid evaluation and screening of commercial surfactants (i.e., Cocamidopropyl Hydroxysultaine, Lauramidopropyl Betaine, Tallow Amine Ethoxylate, N,N,N' Trimethyl-N'-Tallow-1,3-diaminopropane, and Sodium Alpha Olefin Sulfonate) based on their performance to produce supercritical CO 2 foam at high salinity, temperature, and pressure conditions. The microfluidic analogue was designed to represent the pore sizes of the geologic reservoir rock and to operate at 100 °C and 13.8 MPa. Values of the pressure drop across the microfluidic analogue during flow of the CO 2 foam through its pore network was used to evaluate the strength of the generated foam and utilized only milliliters of liquid. The transparent microfluidic pore network allows in-situ quantitative visualization of CO 2 foam to calculate its half-life under static conditions while observing if there is any damage to the pore network due to precipitation and blockage. The microfluidic mobility reduction results agree with those of foam loop rheometer measurements, however, the microfluidic approach provided more accurate foam stability data to differentiate the foaming agent as compared with conventional balk testing. The results obtained here supports the utility of microfluidic systems for rapid screening of chemicals for carbon sequestration or enhanced oil recovery operations.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Fatty acid foams for nonselective physical removal of microplastics from aqueous solutions

Microplastics (MPs) are pervasive environmental contaminants whose removal from water remains a major challenge due to their small size, chemical diversity, and dynamic surface properties arising from environmental aging/weathering. Here, we present a concept of foam-based separation method that physically traps MPs in the foam phase using microtubular assemblies of 12-hydroxystearic acid. These foams are stabilized by anisotropic fatty acid microtubules formed in the presence of ethanolamine, which jam within the foam channels and suppress fluid drainage thereby enhancing MP retention and foam stability. MPs of different sizes, polymer compositions (including polystyrene, polypropylene, polyethylene terephthalate, and polytetrafluoroethylene), and weathered states were retained in the foam phase without requiring chemical modification or relying on chemical interactions between the fatty acid and MPs. Thermally induced transition of the fatty acid microtubules into nanomicelles above the characteristic phase transition temperature (∼35 °C) enables controlled foam collapse and recovery of trapped MPs. The cumulative removal efficiency can exceed 85% through multiple foaming cycles, matching predictions from a probabilistic retention model. This work shows that foams can provide a simple platform to trap MPs, thus providing a new physical-removal strategy that does not rely on the particles’ chemistry.

Guillot, Kennedy A. [Louisiana State Univ., Baton ↗
DOE OSTI2023

Evaluation of the relative importance of preheat from hohlraum x rays and a radiative shock on a low-density foam

Indirectly driven shock-tube experiments were performed on the Omega Laser Facility to evaluate the relative importance of hohlraum x ray and radiative shock preheat sources on a low-density foam. X rays emitted from the hohlraum and a subsequent shock wave are channeled into a low-density foam sample, which contains a plastic preheat-witness disk placed downstream of the foam. Simultaneous radiographic measurements of the shock speed in the foam and the expansion rate of the witness disk due to preheat allow for the observation of effects from the hohlraum's low-energy and high-energy x-ray spectrum. Here we showed, from simulations, that low-energy x rays from the hohlraum are preferentially absorbed near the ablator surface (where the hohlraum and the shock tube meet), while higher-energy x rays largely pass through the ablator and foam and are volumetrically absorbed by the witness disk. Reproducing the experimentally measured shock speed and expansion of the witness disk simultaneously, we extracted the temperature evolution of preheated foam from the simulation and evaluated the relative importance of preheat sources on a low-density foam from hohlraum x-ray radiation and radiative shock. We found that radiation from the shock front was more effective at preheating the low-density foam than the high-energy x rays from the hohlraum. This shock-tube preheat experiment is important for understanding the results of the MARBLE experiments at the National Ignition Facility because initial conditions of foam-filled MARBLE capsules are sensitive to preheat.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2020

Transient computational and experimental thermal analysis of graphite foam monoblock

A densified graphite foam is being explored for its applicability as plasma-facing material in fusion devices. Three different graphite foam monoblocks are constructed and tested in the Garching Large Divertor Sample Testing Facility. The monoblock samples consist of graphite foam press-fit to a single tube, graphite foam cubes brazed to a single, and graphite foam cubes press-fit to a single tube. The tube is composed of CuCrZr with a steel twisted tape. The monoblocks are exposed to the heat fluxes of 5, 6, and 8 MW/m 2 for 30 s to determine the maximum surface and body temperatures measured with thermocouple for each monoblock design. The press-fit monoblocks are exposed to 8 MW/m 2 for 15 s for 100 cycles to determine the effect of thermal cycling on the contact between the graphite foam and the tube. STAR-CCM+ is used to predict how much the contact between the foam and tubes varies as a result of thermal cycling. In addition, the 6 MW/m 2 loading is modeled in STAR-CCM+ to compare the transient cooldown curves of the computational results to the recorded temperatures at the surface and two different thermocouple locations. This comparison is used to validate the temperature-dependent thermal conductivity and specific heat capacity used in the models of the graphite foam. The computational modeling of the experiment has been used to hypothesize ways to use and improve upon the graphite foam as a suitable material for fusion applications.

Gehrig, Monica↗
DOE OSTI2023

Preparation of Macroscopic Low-Density Gold Foams with Good Machinability

Uniform, macroscopic monoliths (ranging from a few millimeters to a centimeter) of low-density gold foams with ~95% porosity and ~10-μm-diameter pores were prepared by the casting of gold-coated polystyrene core-shell particles followed by the thermal removal of the polymer core. The Au foams were composed of unique hollow gold spheres and showed superior mechanical integrity and resilience compared to the foams we previously reported. Highly efficient seeding and electroless gold-plating methods in this study caused a significant morphological transition in the gold coatings from coarse particles to fine particles, and finally, to a continuous layer. A modified, scalable casting approach to form large uniform monoliths (up to ~1-cm diameter) and a gentle baking condition to minimize undesirable densification of the final foams enabled us to develop a simple, efficient synthetic route to nanostructured macroscopic low-density gold foams. To demonstrate the improved mechanical stability and machinability, a representative monolithic Au foam (~0.9 g/cm 3 ) was carefully cut into the hollow cylinder of gold foams by a series of machining and processing steps. Finally, we tried to understand the unique mechanical behaviors and properties of this gold foam by nanoindentation measurement.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2025

Developing Microalgae-Based Non-Isocyanate Polyurethane Foam Materials

Polyurethane is a versatile material with a wide range of applications in the production of foam products such as car seats, mattresses, footwear, insulation foam, and more. The traditional process for producing polyurethane foam involves the fast reaction of isocyanate with water, which generates CO2 as a blowing agent. However, the use of isocyanate has raised concerns due to its potential for causing allergic reactions and aspiration symptoms. This has led to increased regulation of isocyanate, leading to a growing interest in developing alternatives. Non-isocyanate polyurethane (NIPU) has emerged as a promising alternative to traditional toxic PU production. The most promising approach for producing NIPU is the aminolysis of cyclic carbonate with diamine. The NIPU produced through this process has a polyhydroxyurethane structure, which is similar to traditional PU chemistry. We have demonstrated that microalgal oil is a favored feedstock, as it can provide high reactivity for industrial applications. However, the NIPU production process does not generate gas, and a blowing agent is required to achieve the desired foam structure. One of the challenges in producing NIPU foam is to match the bubble formation and curing rates. We have developed a novel approach to producing NIPU foam that utilizes carbamate as a bifunctional blowing and crosslinking agent. We have used vegetable oil and microalgal oil as feedstocks to produce various NIPU for characterization. The development of microalgal NIPU provides an exciting opportunity for reducing the environmental impact of foam production and improving the safety of the materials used in the production process. The production of value-added NIPU foam can also drive down the cost of microalgal biorefinery, advancing the commercialization of microalgal biofuel.

algae↗
DOE OSTI2021

Finite Element Analysis (FEA) for Water-Foam Fracturing of Granite Rock

In addition to the foam data that were obtained from literature and that were collected from the current study, simulation data was also generated from finite element analysis (FEA) conducted in this study using COMSOL Multiphysics software. The FEA models were built to simulate the experiments conducted at Oak Ridge National Laboratory (ORNL) on cement and granite samples. In these FEA models, temperature was kept at ambient while the pressure profile resembled the loading conditions during the ORNL experiments, where pressure was either monotonically increased or applied cyclically. The cement material was used as a model material and was used to study Von Mises stress and tensile stress distribution for different bore hole length geometry using a parametric sweep with water as fracturing fluid using solid-fluid interaction module. For the granite material, FEA models were developed for stress analysis of cylindrical samples with water or foam fluids. The solid mechanics module in COMSOL was implemented to solve for Von Mises stress and tensile stress. The fluid-structure interaction module was implemented to solve for water-foam interaction on granite cylinder with addition of fluid-loading on structure, i.e., large deformation in solid mechanics with no impact on fluid deformation. Foam was considered as a pseudo single-phase compressible fluid for which material properties were calculated from water and gas (nitrogen) phases. The density of foam is calculated as a function of the densities of water and nitrogen, while viscosity is a function of temperature. Four types of FEA analyses were modelled: 1. Monotonic injection with water 2. Monotonic injection with foam 3. Cyclic injection with water 4. Cyclic injection with foam All the COMSOL files are converted to a zip file which is save in .mph.

15 GEOTHERMAL ENERGY↗
DOE OSTI2026

Minimized aging of isocyanurate-based rigid cellular foams for buildings through tailored barrier facers and optimized formulation

The thermal resistivity (h·ft 2 ·°F/Btu/in.) of closed-cell rigid foam insulation materials significantly decreases over time. Diffusion-tight facers are designed to significantly enhance initial thermal resistivity and long-term thermal performance by preventing gas diffusion into the foam cells and inhibiting the escape of low thermal conductivity blowing agents. In addition to the gas diffusion property of the facer film, adhesion between the foam and the facer is crucial for achieving diffusion-tight bonding. Here, this study addresses the challenge of thermal aging by investigating how facer film properties and foam formulation influence the durability of thermal performance. A systematic evaluation was conducted to understand the effects of polymeric barrier films, surface treatments, facer coverage, and foam matrix rigidity on thermal resistivity over time. Key findings reveal that diffusion-tight facers, particularly those with metallized layers and compatible heat seal layers, significantly reduce gas exchange and improve foam-facer adhesion. The optimized system, incorporating barrier facers and a tailored polyisocyanurate foam formulation, achieved initial and aged thermal resistivity values after 200 days of approximately 8.3 and 7.4 h ft 2 ·°F/Btu/in., respectively representing only a 10 % reduction compared to a 17 % reduction observed in control samples without facers. Notably, polyurethane spray foams with facers exhibited only a 4 % reduction in thermal resistivity, compared to a 23 % decrease in control samples, demonstrating nearly six times better retention of thermal performance. This innovative facer technology presents a promising solution for reducing energy costs and represents a significant advancement in optimizing energy management for building envelopes in future technologies. This technology can also be adapted for other applications that necessitate the preservation of long-term thermal performance.

Wanasinghe, Shiwanka Vidarshi [Oak Ridge National ↗
DOE OSTI2022

Mapping 3D grain and precipitate structure during in situ mechanical testing of open-cell metal foam using micro-computed tomography and high-energy X-ray diffraction microscopy

Open-cell metal foams are ultra-low-density cellular metals with complex hierarchical structures that span bulk, cell, ligament, and sub-ligament scales and give rise to desirable properties such as high strength-to-weight ratio and excellent energy absorption. Although literature suggests that intrinsic material structures at sub-ligament length scales (e.g., grains and precipitates) play an important role in mechanical behavior of open-cell metal foams, there are very few experimental measurements of such structures in three dimensions and for meaningful volumes of foam. This study seeks to map and track the three-dimensional (3D) grain and precipitate structures of an intact volume of open-cell aluminum foam by advancing microstructural characterization techniques that leverage X-ray micro-computed tomography (μCT) and far-field high-energy X-ray diffraction microscopy (FF-HEDM). A 6%-relative-density aluminum foam sample was mechanically tested in compression while μCT and FF-HEDM measurements were collected at interrupted loading states at beamline 1-ID of the Advanced Photon Source. Further, a new scanning strategy and reconstruction algorithm were established to enable characterization of a foam volume with diameter approximately four times wider than the nominal width of the X-ray beam. The result is a set of maps that detail both the 3D grain and precipitate structures throughout the foam volume at successive strain steps. A novel grain tracking procedure was developed to track individual grains within the foam volume by accounting for the large rigid-body motions that individual ligaments can undergo during mechanical loading. The ability to track grains and precipitate structures in three dimensions throughout large bulk deformation of ultra-low-density polycrystalline materials enables new possibilities for validating numerical models and investigating local failure mechanisms. Furthermore, the methods and procedures developed in this study could be applied to other ultra-low-density structures, such as additively manufactured lattices.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Comparison of Single-Phase Convection in Additive Manufactured Versus Traditional Metal Foams

Abstract Metal foams have been often used for thermal management due to their favorable characteristics including high specific surface area (SSA), high thermal conductivity, and low relative density. However, they are accompanied by shortcomings including the significant contact resistances due to attachment method, as well as the need for characterization of foam parameters such as pore diameter and SSA. Additive manufactured (AM) metal foams would eliminate the substrate/foam thermal resistance, decrease the need for pre-usage characterization, and allow for tailoring structures, while also taking advantage of the characteristics of traditionally manufactured foams. A commercial, aluminum foam (nominally 5 pores per inch (PPI), 86.5% porosity) was analyzed using X-ray microcomputed tomography, and a custom-designed metal foam based on the cell diameter and porosity of the commercial sample was subsequently manufactured. Reduced domain computational fluid dynamics/heat transfer (CFD-HT) models were compared against experimental data. Postvalidation, the flow behavior, effect of varying attachment thermal conductivities, and thermal performance were numerically investigated, demonstrating the usefulness of validated pore-scale models, as well as the potential for improved performance using AM metal foams over traditionally manufactured foams.

Engineering↗
DOE OSTI2024

Enhancement of the Physical and Mechanical Properties of Cellulose Nanofibril-Reinforced Lignocellulosic Foams for Packaging and Building Applications

Biobased foams have the potential to serve as eco-friendly alternatives to petroleum-based foams, provided they achieve comparable thermomechanical and physical properties. We propose a facile approach to fabricate eco-friendly cellulose nanofibril (CNF)-reinforced thermomechanical pulp (TMP) fiber-based foams via an oven-drying process with thermal conductivity as low as 0.036 W/(m·K) at a 34.4 kg/m3 density. Acrodur®, iron chloride (FeCl3), and cationic polyacrylamide (CPAM) were used to improve the foam properties. Acrodur® did not have any significant effect on the foamability and density of the foams. Mechanical, thermal, cushioning, and water absorption properties of the foams were dependent on the density and interactions of the additives with the fibers. Due to their high density, foams with CPAM and FeCl3 at a 1% additive dosage had significantly higher compressive properties at the expense of slightly higher thermal conductivity. There was slight increase in compressive properties with the addition of Acrodur®. All additives improved the water stability of the foams, rendering them stable even after 24 h of water absorption.

Chemistry↗
DOE OSTI2020

Solvent depression of transition temperature to selectively stimulate actuation of shape memory polymer foams

An embodiment of the invention is a shape memory polymer (SMP) foam designed to recover its original shape through exposure to a solvent. Thermo-responsive SMPs are polymers designed to maintain a programmed secondary shape until heated above their transition temperature, upon which the polymer recovers its original, or primary, shape. The thermo-responsive SMP foam is programmed to its secondary shape prior to use, typically compression of the foam to a small volume, and remains in this programmed shape until exposed to a selected solvent such as dimethyl sulfoxide or ethyl alcohol. Upon exposure to the solvent, the transition temperature of the SMP foam decreases below the temperature of the environment and the SMP foam actuates to its primary shape. The SMP foam is tailored to actuate upon exposure to specific solvents while minimizing or preventing actuation when exposed to water or other solvents. This selective solvent actuation can be used to increase working time of a SMP foam device, that is, the time allowed for use of a device without undesired actuation, while maintaining functional SMP actuation. Solvent actuated SMP foams can be used in various applications including, but not limited to, treatment of aneurysms and arterio-venous malformations, tissue engineering, and wound healing.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Study on Foam Fracturing of Granite for the Development of Enhanced Geothermal Systems

Foam fracturing has been considered as a potential technical approach to address water concerns with hydraulic stimulation in the development of enhanced geothermal systems (EGS). This paper reports the recent progress of a project sponsored by the U.S. DOE GTO Waterless Stimulation Initiative. The project investigates the foam fracturing as an alternative approach to the hydraulic fracturing. The paper describes the development of foam fracturing testing system at Oak Ridge National Laboratory (ORNL). The system can be used to perform the hydraulic fracturing of rock-like materials with both water and foamed fluids under pressure to 6,000 psi (41.4 MPa). The system features the sections of foam generation and foam injection and has the capability of testing materials in both monotonic and cyclic injection modes.Experimental results of foam fracturing on Charcoal Black granite will be reported. Cylindrical granite specimens with a blind hole were studied along with water and nitrogen-gas-in-water foam as the fracturing fluids. The effects of fracturing fluids and injection modes on the breakdown pressure and failure responses of the material were examined. The observations from the experimental work and the implications to the EGS application will be presented and discussed.

Wang, Hong↗
DOE OSTI2021

Solvent depression of transition temperature to selectively stimulate actuation of shape memory polymer foams

An embodiment of the invention is a shape memory polymer (SMP) foam designed to recover its original shape through exposure to a solvent. Thermo-responsive SMPs are polymers designed to maintain a programmed secondary shape until heated above their transition temperature, upon which the polymer recovers its original, or primary, shape. The thermo-responsive SMP foam is programmed to its secondary shape prior to use, typically compression of the foam to a small volume, and remains in this programmed shape until exposed to a selected solvent such as dimethyl sulfoxide or ethyl alcohol. Upon exposure to the solvent, the transition temperature of the SMP foam decreases below the temperature of the environment and the SMP foam actuates to its primary shape. The SMP foam is tailored to actuate upon exposure to specific solvents while minimizing or preventing actuation when exposed to water or other solvents. This selective solvent actuation can be used to increase working time of a SMP foam device, that is, the time allowed for use of a device without undesired actuation, while maintaining functional SMP actuation. Solvent actuated SMP foams can be used in various applications including, but not limited to, treatment of aneurysms and arterio-venous malformations, tissue engineering, and wound healing.

Boyle, Anthony↗