Search Results (4,040)

Electrified mobility regulations and lifecycle emissions targets have increased the demand for lightweight structural materials in vehicle architectures. Bioinspired composite materials offer microstructural configurations that alter conventional trade-offs among specific stiffness, crash energy absorption, and manufacturing energy requirements. This review evaluates the translation of biological structural archetypes including nacre, bamboo, cortical bone, and lotus leaves into load-bearing and functional automotive components. Quantitative benchmarks of continuous natural-fiber laminates, bio-cellular lattices, and mycelium-based acoustic cores are compared against high-strength steel and aluminum alloys. Key mechanical and functional metrics, including specific energy absorption (ranging from 35 to 48 kJ kg⁻¹ for bioinspired crash structures), dynamic loss factors, and Cassie-Baxter superhydrophobic surface stability, are evaluated alongside high-throughput manufacturing routes such as high-pressure resin transfer molding (HP-RTM) and additive manufacturing. Methodological parameters for ISO 14040/14044-compliant Life Cycle Assessment (LCA) are synthesized, emphasizing component-level functional units over gravimetric mass equivalence. Furthermore, operational boundaries, specifically hygrothermal interfacial degradation, matrix glass transitions (T_g < 120 °C), and multi-axial loading sensitivity, are systematically outlined to define design limits for automotive deployment. Full article

The recovery of bioactive compounds from industrial wastewaters is a key strategy for improving resource efficiency and reducing the environmental impact of high-load effluents. In this work, two protein-rich tannery wastewater streams with different origins and compositions, unhairing–liming wastewater and lime-fleshing wastewater, were comparatively evaluated as secondary raw materials for the production of amino acid-based protein hydrolysates with potential biostimulant activity. Both streams were characterised in terms of physicochemical composition, mineral content and amino acid profile, and subsequently subjected to a comparative sequential enzymatic hydrolysis approach using endo- and exo-proteolytic enzymes. Alcalase, followed by Pancreatin, was selected as the most effective enzymatic system for both streams, although different optimal enzyme loadings were required depending on the wastewater composition. For unhairing–liming wastewater, the optimal conditions were 1.5% Alcalase and 1.0% Pancreatin, yielding 70.76 ± 1.95% hydrolysate, 80.87 ± 1.98% protein recovery and 11.42 ± 1.03% free amino acids. For lime-fleshing wastewater, 0.7% Alcalase and 1.0% Pancreatin provided 98.42 ± 1.97% yield, 92.19 ± 1.92% protein recovery and 16.97 ± 0.98% free amino acids. The two hydrolysates showed differentiated amino acid profiles, reflecting the keratin- and collagen-derived nature of the original streams. Germination assays indicated a growth-stimulating effect of the hydrolysates, increasing seed growth by up to 20.7% for the unhairing–liming wastewater hydrolysate at 0.10% (w/v) and by up to 27.1% for the lime-fleshing wastewater hydrolysate at 0.07% (w/v). These results demonstrate that enzymatic hydrolysis can be an effective and environmentally friendly route for converting tannery wastewaters into value-added bio-based products for agricultural applications, while also highlighting the industrial relevance of adapting the enzymatic process to the origin, composition and protein accessibility of each wastewater stream. Full article

Super-liquid-repellent materials hold significant promise for minimizing food residue, suppressing interfacial fouling, and enhancing the cleanability of food-contact surfaces. However, prevailing evaluation paradigms—centered on static contact angle, roll-off angle, and dry abrasion—fail to forecast long-term service performance in complex food-processing environments. Unlike idealized probes, real food matrices comprise proteins, polysaccharides, lipids, surfactants, and microbiota, driving interfacial behavior that is time-dependent, multicomponent-coupled, and dynamically evolving. Consequently, traditional static metrics are inadequate across temporal, chemical, and mechanical dimensions. Furthermore, while “fluorine-free,” “edible,” or “bio-based” labels offer design cues, they cannot substitute for rigorous, lifecycle-resolved assessments encompassing fabrication, aging, migration, and end-of-life impacts. This review delineates the fundamental mismatch between current evaluation frameworks and operational food environments, exposing latent safety and sustainability risks obscured by superficial green claims. We subsequently discuss a dynamic evaluation framework featuring multidimensional metrics and a tiered screening workflow, shifting the paradigm from endpoint-focused assessment to a process-based evidentiary chain. Finally, we outline future trajectories, emphasizing the transition from passive repellency to active fouling modulation and the co-design of performance, safety, and sustainability. This work provides a conceptual blueprint for updating evaluation standards and accelerating the industrial translation of food-contact super-liquid-repellent materials. Full article

Additive manufacturing (AM) can support more sustainable polymer production, but the benefit is conditional on process energy, material chemistry, build yield, post-processing, service life, repair, and end-of-life recovery. This critical integrative review compares three polymer AM routes: stereolithography (SLA), digital light processing (DLP), and fused deposition modelling (FDM) through two deliberately contrasting application scales: pallet-scale load-bearing structures and membrane feed spacers. The review distinguishes direct application evidence from design opportunities inferred from adjacent AM literature. For pallet-scale structures, the literature currently supports large-format thermoplastic extrusion, zoned cellular architectures, modular repair, and controlled recycled feedstock as plausible translation routes, but direct peer-reviewed evidence for fully additively manufactured transportation pallets remains very limited. For membrane feed spacers, direct studies provide stronger quantitative evidence: published 3D-printed designs have reported approximately threefold pressure-drop reduction with doubled specific water flux, pressure-drop gradients as low as 0.091 bar m⁻¹ under reported test conditions, and a 16% increase in permeate flux with a thinner fouling layer for a honeycomb geometry. Process-energy evidence also shows that results depend strongly on the functional unit and machine state; reported desktop values span 24.8–85.7 kJ cm⁻³ for FFF and 10.8–21.5 kJ cm⁻³ for SLA, while post-processing and machine utilization can materially change the lifecycle result. Recycled polymers likewise involve a performance–circularity trade-off: some post-consumer PLA studies report strength losses of about one-third or more, whereas controlled blends and recycling strategies can retain a much larger fraction of virgin-material performance. The synthesis therefore treats geometry, process parameters, material state, operational performance, lifecycle impact, and cost as one coupled design problem rather than assuming that AM, recycled content, or bio-based chemistry is inherently sustainable. Full article

Anthropogenic greenhouse gas (GHG) emissions from chemical manufacturing present substantial operational, compliance, and competitive challenges under international climate accords and emerging regulatory frameworks, including the European Union Corporate Sustainability Due Diligence Directive (CSDDD), the Corporate Sustainability Reporting Directive (CSRD), and the Carbon Border Adjustment Mechanism (CBAM). This study provides an empirically grounded, multi-site decarbonization framework combining longitudinal quarterly operational datasets collected from 14 industrial coating manufacturing facilities (2024–2025) with an audited baseline manufacturing facility producing 35,640 metric tonnes annually. Lifecycle GHG accounting reveals that upstream raw material procurement and synthesis (Category 4) dominate the value-chain carbon footprint, contributing 89.48% (172,557 tCO₂e) of the total 192,834 tCO₂e baseline organizational footprint. In contrast, direct stationary combustion (Category 1) and purchased electricity (Category 2 location-based) account for only 0.89% (1711 tCO₂e) and 2.46% (4741 tCO₂e), respectively. To resolve implementation trade-offs, a Multi-Criteria Decision Analysis (MCDA) framework integrates annual carbon abatement potential, Technology Readiness Level (TRL), capital intensity, and payback dynamics to establish a prioritized Six-Tier Decarbonization Hierarchy: Tier 1 (Priority 1)—upstream bio-based resin and binder substitution, delivering an estimated baseline reduction of 25,880–60,050 tCO₂e/year (13.4–31.1% of baseline emissions); Tier 2 (Priority 2)—drop-in bio-based and circular solvent replacement, achieving 4820–9640 tCO₂e/year (2.5–5.0% baseline reduction); Tier 3 (Priority 3)—thermal process electrification via high-temperature industrial heat pumps (COP 2.5–3.1), eliminating 1027–1369 tCO₂e/year; Tier 4 (Priority 4)—contractual and on-site renewable electricity procurement via corporate Power Purchase Agreements (PPAs) and solar PV (4490–4741 tCO₂e/year; 2.3–2.5% baseline reduction); Tier 5 (Priority 5)—systemic formulation transitions to waterborne, high-solids, and powder coating architectures (15,000–35,000 tCO₂e/year); and Tier 6 (Priority 6)—stream-conditional Carbon Capture, Utilization, and Storage (CCUS), strictly restricted to concentrated combustion stacks (CO₂ ≥ 8 vol%) and excluded from dilute post-thermal oxidizer off-gases (CO₂ ≤ 1–4 vol%) where capture is economically unviable ($180–$260/tCO₂e). Full article

The increasing occurrence of heavy metal ions in water and wastewater streams represents a serious concern for both the environment and human health. The efficient removal of such contaminants requires the development of stable and functional membrane materials capable of combining separation performance with specific metal-binding interactions. This work proposes the use of bio-sourced phenols alongside branched polyethyleneimine and cellulose acetate to develop advanced membranes for the retention of Ni²⁺ and Cu²⁺ ions from aqueous solutions. The chemical modification of the cellulose acetate membrane was confirmed by structural and thermal analysis. Improved thermal resistance between 50–200 °C suggests that chemical interactions as well as hydrogen bonds were developed within the functionalized membranes. The effect of aldehyde modification on membrane chemistry, morphology, thermal behavior, mechanical properties, and filtration performance was systematically investigated. The vanillin-modified membrane showed the best mechanical response, likely due to improved matrix cohesion promoted by its methoxy-substituted aromatic structure. In contrast, the salicylaldehyde-modified membrane exhibited the highest metal-ion retention, reaching approximately 73% for Ni²⁺ and 67% for Cu²⁺ after five filtration cycles. These findings highlight the potential of bio-based phenolic aldehydes as active compounds for designing membranes with tailored morphology, stability, thermal, mechanical, and metallic ion-removal performances. Full article

Polymer aerogels have attracted increasing attention as lightweight porous materials for thermal insulation, separation, adsorption, remediation, and other environmental applications. Their low density and tunable surface chemistry also make them suitable for converting renewable, recycled, and waste-derived feedstocks into value-added materials. However, their overall sustainability remains difficult to assess because most studies focus on material properties, whereas solvent use, drying energy, processing yield, durability, regeneration, and end-of-life pathways are reported less consistently. This review examines sustainable polymer aerogels from the perspectives of cleaner production and waste valorization and focuses on two main features. First, a unified multiscale framework of structure, formation, and performance links network formation mechanisms, pore architecture, and macroscopic behavior across biomass-derived, thermoset, dynamic covalent, hybrid, and recycled polymer aerogels, which are compared in terms of feedstock origin, processing intensity, functional performance, durability, and circularity. Second, structure–property mapping is combined with sustainability-constrained, AI-guided design, with environmental descriptors treated as optimization objectives from the outset rather than as post hoc justifications. Particular attention is given to waste and secondary resources, including agricultural residues, textile waste, paper waste, recycled poly(ethylene terephthalate), and end-of-life tire fibers. The review also discusses how life-cycle assessment, service-based functional units, and minimum reporting standards can help assess whether sustainability claims are supported by measurable environmental benefits. Several recurring limitations emerge from the literature: sustainability is often discussed only qualitatively, processing data are insufficient to support robust life-cycle assessments, solvent exchange and drying remain major environmental hotspots, and circularity claims frequently conflate bio-based content, biodegradability, recyclability, and reusability. Finally, the review discusses how data-driven tools, including literature mining, machine learning, and multi-objective optimization, can support polymer-aerogel design when environmental descriptors are included from the beginning of materials development. The review also proposes a reporting and design roadmap for future work toward polymer aerogels that combine useful performance with lower resource intensity and credible end-of-life value retention. Full article

This review provides a comprehensive analysis of Ylang-Ylang (Cananga odorata) essential oil (YYEO), describing its botany, historical evolution, and global commercial significance. It systematically provides information on traditional extraction techniques such as hydrodistillation, steam distillation, and solvent extraction alongside innovative green technologies, including microwave-assisted distillation (MAD), supercritical fluid extraction (SFE), and ultrasound-assisted extraction (UAE). Conventional distillation methods are compared with greener technologies. The reviewed studies indicate that microwave-assisted processing can reduce YYEO extraction time from approximately 19 h for conventional hydrodistillation to about 40 min while improving the retention of light oxygenated compounds. In particular, light oxygenated compounds have been reported at approximately 81.23% in solvent-free microwave extracts, compared with 69.94% for hydrodistillation and 57.98% for steam distillation. It has also been reported that YYEO contains more than 50 volatile secondary metabolites, with linalool representing about 28% of the oxygenated fraction, while sesquiterpene-rich hydrocarbons can account for up to 63% of the essential oil. The reviewed studies further demonstrate insecticidal, antimicrobial, antioxidant, anti-inflammatory, and neurobiological activities, supporting the potential use of YYEO in sustainable protective materials and health-related applications. Finally, emerging frontiers in protective smart textiles, living fabrics, and sustainable closed-loop manufacturing paradigms are discussed to outline future directions for bio-based material science. Full article

Polyurethane (PU) is widely used in construction, transportation, automotive products, decorative materials, and related industries because its molecular structure can be tailored to diverse service requirements. This versatility has stimulated growing interest in polyurethane-modified asphalt for pavement engineering. This review examines the chemical structure, reaction mechanisms, and principal synthesis routes of polyurethane-modified asphalt and discusses polyurethane-modified emulsified asphalt, polyurethane composite-modified asphalt, and polyurethane-modified asphalt mixtures. Engineering applications in permeable pavements, bridge and tunnel surfacing, as well as crack and pothole repair are also considered. The review further addresses green in situ polymerization, high-content polyurethane systems, waterborne polyurethane, interfacial adhesion, bio-based formulations, recycled asphalt mixtures, and life-cycle performance. The available evidence indicates that polyurethane can improve high-temperature stability, durability, fatigue resistance, mechanical strength, adhesion, and aging resistance. In suitable formulations, it can also reduce production temperatures and construction-related emissions. Economic feasibility, unresolved technical issues, and future research priorities are discussed at the end of the review. Full article

Traditional phenol-formaldehyde (PF) resin adhesives rely on petroleum-based phenolic monomers, facing dual pressures from resource constraints and environmental concerns. Lignin, an abundant renewable aromatic polymer in wood cell walls with a molecular structure rich in phenolic hydroxyl groups, serves as an ideal bio-based precursor for producing green PF resins. Developing lignin-based phenol-formaldehyde (LPF) resins not only enables the high-value utilization of forest biomass but also aligns with sustainable development strategies. However, the large-scale industrial application of lignin remains challenging due to its inherent drawbacks, such as low reactivity. This review focuses on lignin-modified PF resins, systematically summarizing the main physicochemical modification methods—including phenolation, hydroxymethylation, demethylation, and depolymerization activation—along with their mechanisms of influence on resin properties. It compares and discusses the advantages and disadvantages of different modification routes, analyzes current key technical bottlenecks, and prospects future development directions, aiming to provide a reference for research and application of forest-based green adhesive materials. This review concludes that the combination of physical pretreatment and targeted chemical modification is the most promising approach for enhancing lignin reactivity and resin performance. Future research should prioritize developing green modification technologies, such as those based on deep eutectic solvents (DESs) and aqueous systems, and establish quantitative structure–property relationships for lignin-based resins to accelerate the transition of lignin-based phenolic resins from laboratory research to industrial-scale production. Full article

Electrospun zein nanofibers are promising bio-based materials, but producing uniform ultrafine fibers with desirable performance remains challenging. This study examined the effects of process variables and three surfactants on zein fiber formation, diameter, and material properties. Zein solutions (30–40%, w/v) were prepared in glacial acetic acid, and 2% (w/w, based on zein) triethyl benzyl ammonium chloride (TEBAC), sodium dodecyl sulfate (SDS), or span-80 was incorporated into the 30% zein solution. Zein concentration and feed rate yielded fiber diameters of 208.22–1001.90 nm. Surfactants reduced surface tension and increased conductivity, promoting jet stretching and generating uniform fibers with diameters near 100 nm. SDS produced the smallest fibers (98.92 ± 15.20 nm). TEBAC increased tensile strength from 11.08 to 63.26 MPa and improved dimensional retention in water, whereas SDS and span-80 increased elongation at break but reduced strength and stiffness. All surfactants increased wettability and altered intermolecular interactions and secondary structure of zein, although they reduced thermal stability. Overall, surfactants acted as both electrospinning aids and structure-directing modifiers, with TEBAC providing the best balance of fineness, strength, and aqueous stability. These ultrafine, robust, and water-stable nanofibers are promising as functional coating layers for high-moisture food packaging and as carriers for antioxidants or antimicrobial agents. Full article

As a crucial intersection of flexible electronics and embodied intelligent robotics, electronic skin is evolving from single flexible sensors toward a skin-like intelligent system integrating flexible support, signal sensing, environmental protection, signal transmission, and intelligent feedback. With expanding application scenarios, materials must simultaneously meet requirements for softness, stretchability, high strength, self-healing, wear resistance, and long-term stability. Bio-based self-healing polyurethane, leveraging tunable soft–hard segment structures, a wide range of mechanical properties, facile dynamic bond formation, and renewable raw materials, offers a novel material design pathway for highly reliable electronic skin. This review examines the structural and performance modulation of bio-based components—such as castor oil, nanocellulose, lignin, chitosan, tannic acid, and vanillin—in polyurethane coatings, analyzes the mechanisms of non-covalent interactions, dynamic covalent bonds, and multi-dynamic networks in segment motion, energy dissipation, damage repair, and interface reconstruction, and further discusses their adaptation strategies in encapsulation layers, sensing layers, circuit layers, and base layers. Particular attention is paid to polyurethane coatings as protective and functional interface layers, where coating structure, adhesion, mechanical durability, and damage recovery determine the long-term reliability of electronic skin devices. Finally, this review summarizes current challenges in multi-performance synergy, conductive network stability, bio-based component consistency, long-term service, and large-scale fabrication, while envisioning future directions such as intelligent encapsulation, multi-layer synergy, and data-driven material design. Full article

Bio-based phase change materials (PCMs) can increase transient heat storage in lightweight building envelopes, but their performance depends on the climate, transition properties, layer design, and assumptions used to translate thermal loads into carbon and cost indicators. Although PCM optimization, machine learning surrogates, and lifecycle assessment have each been studied extensively, comparatively few studies combine them while explicitly separating simulation-derived thermal outputs from scenario-dependent environmental and economic post-processing and benchmarking bio-based candidates against paraffin on a common wall area basis. This study develops a simulation-based screening framework for a south-facing office wall model using 18,000 EnergyPlus cases, climate-specific machine learning surrogates, TreeSHAP interpretation, NSGA-II optimization, and scenario-based lifecycle carbon and cost accounting. XGBoost achieved pooled held-out R² values of 0.974 for occupied discomfort degree-hours and 0.978 for total annual thermal demand. For Palermo, the directly re-simulated balanced configuration (T_m = 24.8 °C, L_h = 178 kJ/kg, 22 mm thickness, intermediate position) reduced occupant discomfort by 42.6% and the modeled single-zone total thermal demand by 6.0%. Under the central all-electric scenario (SCOP = SEER = 3.0, grid factor = 0.233 kg CO₂eq/kWh, 25 years), scenario-based net lifecycle carbon was −22.1 kg CO₂eq/m² for the analyzed south wall with an 8.0-year environmental payback, compared with −7.4 kg CO₂eq/m² and 19.2 years for RT28 paraffin. Energy savings did not recover the additional investment; the incremental lifecycle cost was +24.1 EUR/m². The theoretical contribution is a transparent, climate-dependent screening logic that couples surrogate interpretation with explicit evidence boundaries; the applied outcome is a palmitic–capric target-property region prioritized for laboratory validation rather than a deployment-ready product. Only directly re-simulated configurations are used for quantitative applied thermal claims; surrogate-only Pareto points are retained as exploratory screening candidates and are not interpreted as validated optima. The numerical results are specific to the modeled south-wall, single-zone boundary; whole-building and cross-regional application requires local recalibration and direct validation. By linking passive comfort, carbon accounting, material innovation, and responsible pre-experimental selection, the workflow is relevant to the decarbonization objectives represented by SDGs 7, 9, 11, 12, and 13. Full article

Existing reviews on micro- and nanoplastic (MNP) removal from water rarely link adsorbent structural features to the molecular interactions governing removal performance. This review addresses this gap by examining MNP adsorption from a mechanism-oriented perspective, mapping six canonical interaction pathways across five adsorbent classes. Adsorption emerges as a system-dependent process governed by the interplay between polymer properties and surface chemistry rather than by the material alone. Interactions such as π–π stacking and hydrophobic affinity dominate for non-functionalized polymers on carbon-rich surfaces, while electrostatic forces and hydrogen bonding become more relevant for oxidised particles. Pore structure becomes significant when particle size and porosity match, whereas chemisorption provides a stronger and faster pathway in systems containing reactive metal sites. Across material classes, differences relate more closely to scalability and sustainability than to intrinsic adsorption capacity. Bio-based materials offer a favourable balance between performance and practical implementation, while more advanced systems provide greater control but remain limited by synthesis complexity. Laboratory capacities often overestimate real performance, and removal efficiency in complex matrices is a more reliable metric. Future progress will depend on improved standardisation, integration with modelling, and validation under realistic conditions to support the transition from laboratory studies to practical applications. Full article

Bio-derived functional materials are key platforms for long-term sustainable environmental remediation. Pine wood fibres (WF) are an abundant and renewable material with functional properties suited to specialized applications, including high density of hydroxyl groups at its surface and mechanical toughness imparted by the lignin fraction. In the present work, monometallic and bimetallic nanoparticles (MNP) of first-series transition metals, Fe, Co, Cu and Fe/Cu were immobilized onto original WF and WF treated with NaOH (WF_N). The prepared WF-supported MNP were characterized by SEM/EDS, XPS, XRD and FTIR-ATR, and evaluated in the catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in aqueous solution, at room temperature, by NaBH₄. Copper-based materials exhibited superior catalytic efficiency, with the NaOH pre-treatment of the fibres yielding shorter induction times and enhanced stability. For the WF_NCu material, 97% of 4-NP reduction was achieved in 3 min with a rate constant of k¹ = 2.147 min⁻¹. This material was used for five successive cycles with no decrease in 4-NP reduction efficiency, being easily recovered from the reaction media. Full article