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At least 19 records

Life-cycle analysis of microalgae-based polyurethane foams

Polyurethane plastics are essential in many consumer and commercial products such as insulation, furniture, automotive interiors, and clothing. Pathways for producing polyurethane from microalgae offer an opportunity to reduce greenhouse gas emissions and other environmental impacts and can incorporate processes that avoid the use of toxic isocyanates typically used in conventional polyurethane production processes. In this study, the greenhouse gas emissions, fossil energy, and water consumption of biobased polyurethane and biobased non-isocyanate polyurethane were evaluated via life-cycle analysis using the R&D Greenhouse Gases, Regulated Emissions, and Energy Use in Technologies model. Microalgae-based polyurethane foam was found to achieve greenhouse gas emission reductions of up to 79% compared with conventional polyurethane foam production. The greenhouse gas reductions for the non-isocyanate microalgae polyurethane pathway are slightly lower at 58% compared with conventional polyurethane foam. However, it offers additional benefits by reducing toxicity potential compared to the isocyanate polyurethane pathway. The analysis also included a biorefinery-level analysis to evaluate the impact of incorporating polyurethane production into fuel-processing microalgae biorefineries. The sensitivity analyses conducted in this study reveal that improved algae cultivation strategies can lead to decreases of up to 127% and 80% in GHG emissions from the baseline process of Bio-PU and Bio-NIPU, respectively. Likewise, implementation of renewable electricity can result in up to 128% and 74% lower GHG emissions compared to the baseline production of Bio-PU and Bio-NIPU, respectively. Finally, the analysis evaluated different coproduct handling methods including displacement and allocation (based on mass, energy, and market-value). The results suggest that it is important to consider both the displacement and allocation methods as these led to significant differences in the environmental impacts.

36 MATERIALS SCIENCE

Synthesis and Characterization of Soy Hull Biochar-Based Flexible Polyurethane Foam Composites

Flexible polyurethane foams are a diverse class of materials encompassing furniture, packaging, automotive, and many other industrial and domestic applications. Polyurethane foams are synthesized by the addition of polyols and isocyanates; however, the petroleum origin and toxic nature of isocyanates have driven many to look for more sustainable routes to production. Renewable fillers have emerged as a biobased resource to decrease the carbon footprint of this widely used polymeric material. In this study, soy hulls, as mass-produced, industrial by-products of soybean production, were used to create a biochar beneficial in the synthesis of flexible polyurethane foam composites. The addition of soy hull biochar was found to maintain the compression properties of foams at a decreasing isocyanate index, reducing the amount of isocyanates needed for production. In addition, the addition of biochar decreased the flammability of foams, important for many applications where consumer safety is important. The results point to the ability to create safer, more sustainable, and even more cost-effective polyurethane foams through the reduction in isocyanate use while maintaining the properties of this important class of polymers.

Chemistry

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

Challenges and Perspectives in Lignin‐Derived Polyurethane Foam Synthesis

Abstract Polyurethane foams (PUFs) represent a significant segment of the polyurethane (PU) and cellular plastics industries, owing to their versatile applications and desirable properties. However, the production of PUFs heavily relies on petroleum‐derived chemicals, including polyols and isocyanates, raising critical environmental concerns. Lignin, an abundant aromatic macromolecule, offers a promising alternative for replacing petroleum‐based polyols because of its intrinsic hydroxyl groups. While efforts have been made to produce and apply various lignin‐based polyurethane foams (LPUFs), their commercialization remains limited by challenges such as low product consistency, poor technical performances, and high production costs. This study critically evaluates recent advances in the development of LPUFs, including innovative synthesis methods, functional applications, and emerging research trends. Moreover, potential strategies are discussed, such as lignin fractionation, modification, and co‐solvent assistance, for addressing the challenges. By resolving them, LPUFs could play a pivotal role in transitioning the PU industry to help achieve a circular bioeconomy.

Zhang, Mairui [Carl and Melinda Helwig Department

Green co-solvent-assisted one-pot synthesis of high-performance flexible lignin polyurethane foam

Although lignin is a promising candidate as a source of polyol for producing eco-friendly polyurethane foam (PUF), its direct application has limitations, primarily stemming from the brittleness of the resulting products and poor processibility at high lignin loadings. To address these technical challenges, we introduced an effective co-solvent for the lignin-based polyurethane foams (LPUFs) with up to 80wt% of lignin substitution for petroleum polyols. As a green co-solvent that involves carbon dioxide fixation during its production, propylene carbonate (PC), was blended with lignin and improved the distribution of lignin by decreasing the viscosity, providing a room-temperature reaction. The LPUFs demonstrated a comparable thermal insulation performance (R-values greater than 5 in -1 ) with commercially available PUF with a uniform size of closed-cell structure induced by the reduced viscosity of lignin-based polyol. LPUFs also showed enhanced fire retardancy and moisture resistance compared to the control PUFs, benefiting from lignin’s intrinsic fire-resistant and hydrophobic properties. To mitigate the brittleness issue at high lignin loadings, flexible polyethylene glycols (PEGs) with a high molecular weight (i.e., PEG-1000) were dissolved in PC at room temperature to further improve the mechanical strength of LPUFs. The compressive strength of LPUFs with 80 wt% lignin substitution content was remarkably improved to 226 kPa by the employment of co-solvent and PEG-1000 compared to the control PUF (<140 kPa). Moreover, the flexibility of the LPUFs was successfully controlled by simply adjusting the PEG-400/PEG-1000 ratio. In conclusion, the results of this study provide valuable insights for accelerating and broadening the utilization of lignin in sustainable materials and manufacturing areas.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH

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

Properties and performance of lignin-based polyurethane foams from lignin and castor oil as synergistic bio-polyols

Lignin and castor oil with intrinsic hydroxyl groups are attractive green resources for polyurethane (PU) applications. However, lignin's heterogeneous and highly crosslinked structure, poor processability, as well as the feedstock variability, lead to inconsistent and poor performance of the final foam products. Castor oil-based polyurethane foam (PUF) has a relatively high price and density, which are big hurdles to its practical applications. Here, in this study, we hypothesized that synergistic bio-polyol mixtures composed of lignin and castor oil could balance the drawbacks from individual component. Castor oil could improve the dispersity of lignin, while lignin simultaneously addressed the issues caused by PUF prepared with castor oil, such as its high density and low thermal stability. For a comprehensive understanding of the effects of structural properties of lignin on its PUF processing and applications, various lignin fractions were isolated by co-solvent enhanced lignocellulosic fractionation (CELF) from different species, including hardwood, softwood, and herbaceous plants, and the processed lignins with different molecular weights were applied with castor oil. The lignin fractions with lower molecular weight showed good dispersity in castor oil with a high lignin content (up to 50 wt%) and completely replaced petroleum-based polyols. The produced foam with 50 wt% low-molecular-weight lignin fractions from woody biomass showed comparable/higher compressive strength (up to 20 psi) and thermal insulation performance (up to 5.69 R-value in −1 for 50 % L-Pine foam). In addition, this study revealed the relationship between lignin's structural properties and foam performance, providing insights for practical applications of lignin-based PUF.

Jeong, Soyeon [State Univ. of New York (SUNY), Syr

Use of Captured CO2 for Production of Sustainable Polyurethane Foams in Automotive Applications

Captured CO2 has been investigated as a feedstock for the production of polyurethane (PU) foams for automotive applications. Previous work has shown successful incorporation of CO2 into polyols via three distinct reaction pathways. These CO2-derived polyols, as well as several commercially available polyols with varying CO2 content, were used to produce PU foams for automotive seating and NVH (noise, vibration, and harshness) applications. Foam formulations were optimized to maximize sustainable content while maintaining manufacturability constraints and performance requirements for each end use application. PU foams were first formulated at lab scale to confirm free rise and molded foam properties, then scaled up to pilot and industrial scales to evaluate production manufacturing feasibility. Finally, CO2-derived foams were used to produce molded components for end use product validation. Life cycle assessment (LCA) was used to quantify the environmental impact of using captured CO2 and bio-renewable content into polyols and PU foams through the metrics of global warming potential and embodied energy. Tradeoffs among environmental impacts, energy usage, manufacturability, and PU foam performance from the incorporation of CO2 and bio-renewable content will be discussed.

Lee, Ellen [Ford Motor Company]

Enhancing The Thermal Resistivity of Rigid Polyisocyanurate Foam Insulation

The development of rigid polyurethane foam insulation has garnered considerable attention because of its promising applications in the buildings and construction industry. Its low thermal conductivity makes it an attractive choice for improving energy performance in buildings. Current Rigid Polyurethane foams have thermal resistivity (R-value/in.) 5.5 to 6.5 h.ft2F/BTU/in.· that could be further improved by diminishing the heat transfer through the foam matrix. Nevertheless, minimizing both conduction (through gas and solid) and radiation simultaneously in porous solids is a significant challenge due to the trade-off between these two mechanisms. This study focuses on improving the R-value of the insulation foams via several strategies: such as type and the amount of the surfactants, blowing agent content and precooling and premixing polyol mixture. These methods optimized thermal properties of the PIR foams, achieving R/in. as high as 8.3. This excellent R/in. is anticipated to be a critical factor in significantly advancing the thermal insulation performance of rigid polyurethane cellular foams, thereby enhancing their efficacy in energy-efficient building applications.

Wanasinghe Mudiyanselage Pahala Gedara, Shiwanka V

Exploring strain rate effects upon 3D materials using high speed in situ X-ray tomoscopy

Cellular materials are ubiquitous in our modern society. They may be stochastic gas-blown foams (e.g., polyurethane), foamed starches (e.g., cereals), or, in this case, 3D printed microlattices. Failure in these materials is often driven by surface or sub-surface defects, which may be nucleated at a surface roughness, an interior void, or inclusion interfaces that may not be typically observable. Obfuscating our understanding further, bulk materials are known to exhibit strain-rate-dependent mechanical response, making a subsurface understanding of damage even more critical. For the first time, an in situ uniaxial mechanical loading stage that simultaneously rotates specimens up to 18 Hz was fielded at a synchrotron for 3D tomographic imaging. This capability opens a plethora of materials science opportunities to explore strain rate effects in materials and examining deformation, fracture, and delamination’s (in composites) for a complete 3D picture (movie) of material response. We demonstrate the deformation of 3D printed polymer lattice structures, of three different material types, at 0.25, 1.1, and 2.2 s −1 strain rates. We successfully imaged the 3D deformation of these materials and can directly compare the same printed structure to the three material types at three strain rates, all in 3D. Material point method simulations were applied to one of the materials to better understand the role of voids on the 3D printed structure’s performance.

36 MATERIALS SCIENCE

Synthesizing, Compounding, and Characterizing a Heat Labile Foam (SRNL-STI-2025-00653)

Degradable polyurethane foams can be an attractive material to use for packaging, transporting, and dispositioning of nuclear materials. This LDRD project explored the possibility of finding a suitable polyol component that would achieve the intended results. Significant improvements were made on the initial findings of a three month Visiting Faculty Program.

Kranjc, Mark D. [Savannah River National Laborator

First ARM Mobile Facility (AMF1) Aerosol Observing System (AOS01) Instrument Handbook

The U.S. Department of Energy Atmospheric Radiation Measurement (ARM) user facility Mobile Aerosol Observing System – Aerosols (MAOS-A), designated AOS01, entered service in March of 2012 at the Los Alamos National Laboratory for the Pajarito Aerosol Coupling to Ecosystems (PACE) field campaign. The Aerosol Observing System is meant to be a standalone, completely autonomous, aerosol sampling system. It requires only power, 208VAC 1φ or 440 VAC 1φ, and an internet connection to be operational. The physical structure is a standard-sized shipping container, 20 feet long by 8 feet wide. Inside, the walls, ceiling, and floor are insulated using >3.5” of spray polyurethane foam with an R-value of 6.2/inch of insulation. The interior walls, floor and ceiling are lined with ¾” plywood for durability and have integrated unistrut for mounting equipment.

54 ENVIRONMENTAL SCIENCES

Comparison Study of Conventional and Adaptive Mesh Refinement in Organic Material Decomposition Models

This study compares conventional mesh refinement techniques, specifically Uniform Mesh Refinement (UMR), with a new Adaptive Mesh Refinement (AMR) method, applied to Organic Material Decomposition (OMD) models. The proposed benefit of AMR is that only areas that require refinement, based on minimizing a specific field gradient, are refined thus decreasing model wall time compared to conventional UMR methods. This work specifically focuses on comparing UMR and AMR methods on decomposing (both No-Flow and Porous-Flow material models) Polymeric Methylene Diisocyanate (PMDI) polyurethane foam. Throughout the work, the geometry increased in complexity to assess the refinement methods performance at varying levels geometric intricacy. While AMR has been shown to work well in a variety of applications, the UMR approach proved to be computationally faster, for many of the geometries and foam decomposition models, than AMR. However, it was observed that at higher levels of refinement, greater than 3 UMR, AMR begins to be computationally better. Additionally, the settings used to perform AMR greatly impact its performance, and lessons learned, in terms of OMD models, are shared. Due to physics involved in material decomposition, specifically the evolution of state variables, these problems don’t fully benefit from the advantages of AMR.

36 MATERIALS SCIENCE

Develop Renewable/Sustainable Material to Displace Petroleum-Derived Polymer Foams (CRADA Final Report)

NLR and EDEN will partner together to develop renewable, biodegradable alternatives to polyfoam (polyurethane) polymer foams. The initial focus will be on developing cellulose-based foam with tunable mechanical properties. NLR will produce and test the cellulose-based foam materials and characterize its microstructure and mechanical properties. Relationships between mechanical performance formulation and fabrication methods will be developed.

09 BIOMASS FUELS

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

Shape‐Stabilization of Phase Change Materials with Carbon‐Conscious Poly(hydroxy)Urethane Foams

Thermal energy regulation is a significant challenge, contributing to over 30% of annual greenhouse gas emission (GHG) emissions. Phase change materials (PCMs) offer a promising solution by storing thermal energy, which can enable the reuse of waste heat for heating and cooling; however, developing materials for shape-stabilized PCMs remains crucial. This work investigates a self-foaming poly(hydroxy)urethane (PHU), derived from a non-isocyanate polyurethane (NIPU), as a porous support for shape-stabilizing paraffinic and salt hydrate PCMs. PHU-encapsulated paraffinic PCMs exhibited excellent thermal stability over repeated cycles. Thermal stability with salt hydrate PCMs, specifically calcium chloride hexahydrate (CaCl 2 •6H 2 O), is achieved by the incorporation of 5 wt.% barium carbonate (BaCO 3 ) into the PHU foam. This enabled stable cycling for over 48 cycles with desirable thermal properties, i.e., a melting point ≈30 °C, high enthalpy (ca. 138 J g −1 per cycle), and a consistent freezing point ≈20 °C, making it suitable for applications in buildings and electric vehicle battery insulation. Also, incorporating graphite (1.5–10 wt.%) into the foam enhanced the thermal conductivity of shape-stabilized CaCl 2 •6H 2 O during heating and cooling cycles. Overall, the approach detailed here offers a carbon-conscious and chemically tunable material for thermal energy storage.

25 ENERGY STORAGE