Sustainable Materials Research Articles

Characterization of novel bio-plasticizer from Cissus quadrangularis linn. stem: A sustainable and cleaner material for futuristic applications

There is also an increase in demand for plasticizers derived from natural resources, which are biodegradable. In search of novel bio-plasticizers, Cissus quadrangularis linn. (CQL) plant identified serves as an ideal source for plasticizer from natural sources. In this context, plasticizer is extracted from Cissus quandrangularis linn. stem that are biodegradable and biocompatible. This research paper presents the extraction and characterization of plasticizers derived from Cissus quadrangularis linn. (CQL) stem as a substitute for synthetic plasticizers. Bio-Plasticizers from CQL stem are extracted through chemical processes: amination, alkalization, filtration and surface catalysis. Further to identify its plastic nature, different characterization techniques such as FTIR, Thermal analysis, XRD, density, micrographs from SEM, chemical composition from EDX surface texture from AFM are conducted. TGA results convey that the Cissus quadrangularis linn. plasticizers (CQLP) are thermally stable upto 2230 C and displays a lower glass transition temperature of 58.170 C and these results accomplish the desired thermal properties. Crystalline properties of CQLP are found to be good with values of Crystalline Index 72.95 % and Crystalline Size 2.32 nm and these results displays the crystalline nature of isolated plasticizers. Surface texture of CQLP identified from AFM is smooth and uniform with lower roughness values across horizontal and vertical directions. Results of characterization studies accomplishes that novel CQLP are biodegradable, compatible and possess good plasticizing effect. This research investigation shows that these novel CQLP proves as a reliable alternative to synthetic plasticizers.

Optimization in Extrusion Process for Polypropylene and High-Density Polyethylene Pellets in Additive Manufacturing of 3D Printing Filament

The increasing demand for sustainable and cost-effective materials in additive manufacturing has driven research into optimizing the extrusion process for creating 3D printing filament from Polypropylene (PP) and High-Density Polyethylene (HDPE) pellets. This study explores the critical parameters in the extrusion process, including temperature, and screw speed, to enhance the quality and consistency of the resulting filament. Through a series of controlled experiments, we analyze the effects of these parameters on the filament’s diameter, mechanical properties, and printability. Our findings demonstrate that by optimizing these variables, it is possible to produce high-quality 3D printing filament with excellent mechanical strength and dimensional accuracy, meeting industry standards. This research not only contributes to the broader adoption of PP and HDPE in 3D printing but also supports the development of more sustainable manufacturing practices by utilizing recyclable materials.

Sustainable Passenger Services and Child-Friendly Airport Experience: A Case Study of Istanbul Airport

This study explores the concept of child-friendly airports, using Istanbul Airport as a case study to understand how such environments can enhance the travel experience for families with children. Through qualitative research methods, including focus group discussion and in-depth interviews with 12 mothers and 12 field specialists, the research identified key attributes that constitute a child-friendly airport. Building upon the Place Diagram model, the results revealed that a child-friendly airport should prioritize sociability, comfort and image, uses and activities, and access and linkages, aligning with the model’s core themes. The results further identified numerous sub-themes linked to these four themes. Accordingly, airports should offer diverse play areas, family-friendly seating, efficient wayfinding, and high-quality, sustainable materials to create a safe, inclusive, and engaging environment for passengers with children. The study emphasizes the importance of designing airports that cater to the needs of children and their families, contributing to social equity and enhancing the overall passenger experience. These insights can serve as a benchmark for other airports aiming to improve their service offerings for families, supporting sustainable development goals related to reducing inequalities and promoting inclusive, safe, resilient, and sustainable environments. This study represents the first academic attempt focusing specifically on comprehensive services for passengers with children and the broader concept of child-friendly airports.

Feasibility of coal bottom ash as fine aggregate in strain-hardening cementitious composites: A study on strength, durability, and sustainability

The search for cost-effective and sustainable materials for strain-hardening cementitious composites (SHCC) has led researchers to explore alternatives to silica sand, a critical yet costly and environmentally unfavorable material. Although river sand seems like a cheaper and viable alternative, its extraction is linked to severe environmental degradation. This study aims to investigate the potential of coal bottom ash (CBA) as a replacement for silica sand in SHCC, targeting to meet the minimum requirements for structural applications. The novelty of this research lies in its comprehensive exploration of CBA as a partial to full replacement for silica sand (at 0 %, 25 %, 50 %, 75 %, and 100 %), extending beyond the replacement limit investigated in previous studies on SHCC, and provides an extensive evaluation of the composite’s fresh, mechanical, durability, and microstructural properties. Additionally, it includes a thorough assessment of the leaching potential, CO₂ emissions, energy consumption, and cost implications of the CBA-SHCC, which have not been fully explored in earlier CBA-SHCC research. The findings indicate that the reduction in mechanical strength was minimal (0.5 %-10 %) across all CBA replacement levels. Notably, all mixes demonstrated typical strain-hardening behavior, sustaining higher flexural loads beyond the first crack, with increased deflection capacity observed at higher CBA contents, peaking at 50 % replacement. Durability metrics, including water absorption and HCl acid attack resistance, exhibited a downward trend with higher CBA content but remained within acceptable limits up to 75 % replacement. Toxicity characteristic leaching procedure results confirmed the non-leachability of toxic elements in both the CBA and CBA-SHCC mixes. Economically and environmentally, CBA proved advantageous, resulting in 1.5–5 % lower CO2 emissions, 0.4–1.5 % lower energy consumption, and 18–84 % cost savings at 25–100 % CBA replacement. Additionally, a multicriteria analysis using the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) was employed, which identified 25 % as the optimal CBA content that balances fresh properties, mechanical strength, durability, environmental sustainability, and cost efficiency. The study is significant because it demonstrated that CBA can be used as a sustainable and cost-effective alternative to silica sand in SHCC, with lower environmental impact while maintaining structural integrity.

From Fossil to Bio-Based AESO–TiO2 Microcomposite for Engineering Applications

Environmental issues and the reduction of fossil fuel resources will lead to the partial or total substitution of petroleum-based materials with natural, raw, renewable ones. One expanding domain is the obtaining of engineering materials from vegetable oils for sustainable, eco-friendly polymers for different applications. Herein, the authors propose a simplified and green synthesis pathway for a thermally curable, acrylated and epoxidized soybean oil matrix formulation containing only epoxidized soybean oil, acrylic acid, a reactive diluent (5%) and just 0.15 mL of catalyst. The small amount of reactive diluent significantly reduced the initial system viscosity while eliminating the need for adding solvent, hardener, activator, etc. Both the thermally cured composite with a 2% TiO2 microparticle filler and its pristine matrix were comparably characterized in terms of structural, thermal, morphological, dielectric and wettability by Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetry, scanning electron microscopy, broadband dielectric spectrometry and contact angle measurements. The 2% filler in the composite generated superior thermal stability via lower mass loss (48.89% vs. 57.14%) and higher degradation temperatures (395 °C vs. 387 °C), increased the glass transition temperature from −20 °C to −10 °C, rendered the microcomposite hydrophobic by increasing the contact angle from 88° to 96° and enhanced dielectric properties compared to the pristine matrix. All investigations recommend the microcomposite for protective coatings, capacitors, sensors and electronic circuits. This study brings new contributions to green chemistry and sustainable materials.

Upcycling Agency: Material and Human Transformation for Sustainability in Fashion

Upcycling Agency: Material and Human Transformation for Sustainability in Fashion

Performances of starch foam improved by an alginate coating

This research aims to develop an environmentally friendly food packaging based on starch foam coated with alginate. The foam was coated with various concentrations of an alginate solution (0, 0.5, 1.0, 1.5, and 2.0 %w/v). The effects of these coatings on the properties of starch foam were then investigated. The results showed that the alginate coating increased the density of the starch foam. Starch foam coated with the alginate solution at a concentration of 1.0 %w/v showed the optimum flexural stress at maximum load (4.72 MPa), hardness (96), and mass loss in water (5.51 %). These results showed significant improvements in these properties by comparison with the uncoated foam. The alginate coating slightly improved the thermal stability of the starch foam and did not significantly delay the biodegradation of the starch foam in soil. In conclusion, coating starch foam with an alginate solution presents a viable approach to developing sustainable food packaging materials with enhanced mechanical and water resistance properties.

Expanded Perlite-Reinforced Alginate Xerogels: A Chemical Approach to Sustainable Building and Packaging Materials

In sustainable construction and packaging, the development of novel bio-based materials is crucial, driving a re-evaluation of traditional components. Lightweight, biodegradable materials, including xerogels, have great potential in architectural and packaging applications. However, reinforcing these materials to improve their mechanical strength remains a challenge. Alginate is a promising matrix material that may be compatible with inorganic fibrous or particulate materials. In this study, biocomposite xerogel-structured foam materials based on an alginate matrix with expanded perlite reinforcement are improved using certain additives in different weight ratios. The plasticizers used include glycerol and gum arabic, while chitosan was added as an additional reinforcement, and iota carrageenan was added as a stabilizer. The tested specimens, with varying weight ratios of the added components, showed good mechanical behavior that highlights their potential use as packaging and/or architectural materials. The influence of the presence of different components in the composite material specimens on the modulus of elasticity was investigated using SEM images and FTIR analyses of the specimens. The results show that the specimen with the largest improvement in the elastic modulus contained a combination of chitosan and glycerol at a lower percentage (1.96 MPa), and the specimen with the largest improvement in tensile strength was the specimen containing chitosan with no plasticizers (120 kPa), compared to cases where combinations of other materials are present.

Enhancing the mechanical properties of flax fiber-reinforced epoxy composites through cellulose nanofiber incorporation

Cellulose nanofibers (CNFs) have attracted significant attention as effective reinforcements for polymer composites because of their outstanding mechanical and structural properties. This study explored the incorporation of CNFs into flax fiber reinforced epoxy composites to enhance their overall performance. To overcome the challenges of CNFs dispersion, an innovative approach was developed in which CNFs were preloaded onto flax fabrics before resin infusion using vacuum assisted resin transfer molding (VARTM) method. The morphological, mechanical, structural and thermal properties of the composites were comprehensively evaluated for various CNFs loadings (0.1, 0.3, and 0.5 wt%). Remarkably, a 0.3 wt% CNFs loading was found to significantly optimize the composite's Young's modulus, achieving a notable improvement of 204.02 %. This study underscores the potential of CNFs enhanced flax fabric composites for developing high-performance sustainable materials suitable for wide range of technical applications.

Bamboo in Contemporary Architecture: A Composite Climate in India

The rapid pace of growth requires the creation of appropriate space through infrastructure development. However, it's crucial to prioritize environmental considerations and additional construction's necessity. Bamboo, a versatile and sustainable material, holds immense architectural potential, especially in regions like Central India and Uttar Pradesh (UP) where it is abundantly available. To maximize the use of locally available bamboo in India's composite climate, investigate its properties, address usage challenges, and assess its potential as a sustainable material.Bamboo can be used structurally and non-structurally. Dendrocalmus strictus, Bambusa Bamboos, and Bambusa Balcoa are the locally available species that can be grown in local regions. Can be used for making temporary toilets near rivers, and sitting spaces that can be changed after 15 years. Can be used in making facades as well as interior walls.

Model based ranking of the influence of geometry and materials on the dynamical behavior of the violin highlights predominance of geometrical choices

When considering the vibroacoustical behavior of the family of violin instruments, especially related to their construction, numerous beliefs and theories coexist that are not necessarily compatibles between each other. More specifically, the resulting sound or dynamics of the instrument are associated to tonewood properties and geometry, but with ranking and weights that vary according to beliefs and testimony of makers. This study presents an approach to understanding the relative influence of both geometrical and material properties on the vibrational dynamics of the violin. By conducting a screening analysis, using finite element method based computations of a complete violin, we explore impact of maker’s choices during the construction process. The results highlight that the dynamical behavior of the violin is mainly depending on geometrical choices, such as thickness of back and top plate or f-holes shapes, rather than the complete variability of properties of tonewoods. Therefore, the wood selection appears to be a second order effect compared to other luthier’s choices, supporting a craftsmanship practice and can pave the way to the use of lower grade woods, which are more in adequacy with what the resource can offer. This work offers new insights that can assist violin makers in optimizing their design choices and adapting to sustainable material use without compromising subsequent behavior.

Research on Sustainable Design of Smart Charging Pile Based on Machine Learning

With the rapid growth of the electric vehicle market, the importance of the user experience and product sustainability requirements for intelligent charging stations has become increasingly significant. However, accurately capturing the complex associations between design features and sustainability elements remains challenging. Therefore, this study aims to balance user needs and environmental standards in designing smart charging piles, ensuring adherence to symmetry principles. This balance addresses the growing demand for personalization and ensures sustainability. In this paper, the semiotic approach to product construction (SAPAD) model is introduced to analyze the user behavioral process in depth and clarify the core needs of users. Subsequently, these core needs are translated into specific technical requirements for products, and a correlation matrix linking user needs with product technical requirements is constructed using fuzzy quality function deployment (FQFD) to identify design features that fulfill the user requirements. The sustainability factors are then comprehensively evaluated and prioritized based on three dimensions: economic, environmental, and social, i.e., the triple bottom line (TBL). Furthermore, a mapping matrix is developed to connect the design features and sustainability factors, which is combined with the particle swarm optimization–random forest (PSO-RF) algorithm to predict the sustainability factors associated with design features that meet users’ needs. The number of branches m and the maximum depth d of the random forest (RF) algorithm are optimized using the particle swarm optimization (PSO) method. The results indicate that the SAPAD-FQFD model effectively identifies the user needs and relevant product design features. In contrast, the PSO-RF model adeptly manages the nonlinear relationships between charging pile design features and various sustainability factors, e.g., aesthetics and material selection, ensuring that the intelligent charging pile meets users’ core needs in terms of form and function, while embodying the principles of design symmetry. This integrated approach effectively bridges the gap between user needs analysis and product functional design, ensuring the sustainability of the design solution. This study contributes a sustainable framework for the development and design of smart charging piles and related products, further promoting the adoption of green design principles and symmetry design concepts within the supporting infrastructure of new energy vehicles.

Optimizing Hempcrete Properties Through Thermal Treatment of Hemp Hurds for Enhanced Sustainability in Green Building

This study examines the effects of the thermal pre-treatment of hemp hurds on the physical, mechanical, and thermal properties of hempcrete, evaluating its potential as a sustainable building material. Hemp hurds were pre-treated at various temperatures (120–280 °C) and characterized by proximate analysis, CHNS elemental analysis, and thermogravimetric analysis (TGA). The resulting hempcrete samples were analyzed for density, water absorption, compressive strength, and thermal conductivity. Three different hempcrete formulations, with varying lime:hemp proportions, were analyzed. The findings indicate that higher pre-treatment temperatures lead to reduced density and water absorption across all formulations. Formulations containing a higher hemp hurd content had lower densities but higher water absorption values. Compressive strength increased consistently with the pre-treatment temperature, suggesting that higher temperatures enhance matrix bonding and structural rigidity, and with the lime content. However, thermal conductivity also rose with pre-treatment, with only the composition containing the highest hemp hurd content maintaining the optimal insulation threshold (0.1 W/mK). This suggests a trade-off between compressive strength and insulation performance, influenced by the balance of hemp hurd and lime content. These findings underscore the potential of thermal pre-treatment to tailor hempcrete properties, promoting its application as a durable, moisture-resistant material for sustainable building, though the optimization of hurd–lime ratios remains essential.

Thermoplastic Molding of Silk-Curcumin Sustainable Composite Materials with Antibacterial Properties.

Silk fibroin (SF) is a natural protein generated from the Bombyx mori silkworm cocoons. It is useful for many different material applications. Versatile aqueous process engineering options can be used to support the morphological and structural modifications of silk materials related to tailored physical, chemical, and biological properties. Conventional solution-based processing methods, while effective, present process control limitations, thus, thermoplastic molding of regenerated SF-based composites was pursued to fabricate dense, functionalized plastics consisting of silk and curcumin. Curcumin, the active compound in turmeric (Curcuma longa) was incorporated into SF during the high-temperature processing, with the objective to investigate composite thermoplastics with enhanced biological properties from the curcumin due to the protective role of silk during processing. The results showed that a significantly higher amount of curcumin (∼25-fold) could be added into thermoplastic molded silk materials compared with the solution route, attributed to the hydrophobicity and low solubility of curcumin in solution-based routes. The curcumin-incorporated silk thermoplastics provided stability in acidic environments like the human gut, and slow curcumin (∼2% over 8 days) release from the materials. The protective silk-curcumin materials supported improved cytocompatibility with immortalized human colorectal adenocarcinoma (Caco-2) cells at high doses. The intestinal epithelial barrier integrity based on zonula occluden 1 (ZO-1) testing showed that the higher amount of curcumin in the thermoplastic molded silk had no negative effects on the intestinal barrier. The functionalized silk-based plastics also displayed microwave stability and antibacterial efficacy against both Gram-positive S. aureus and Gram-negative E. coli. These silk-based sustainable plastics, functionalized with curcumin, offer potential utility for a range of consumer and medical devices.

Hybrid Composites: Graphene Oxide and Woven Natural Silk Reinforcement for Epoxy Matrix

The integration of graphene oxide (GO) and woven natural silk as hybrid reinforcements in epoxy composites offers a novel approach to high-performance, sustainable materials for structural applications. Combining GO (0.3–1.5 wt.%) and natural silk (40–60% by volume) is hypothesized to significantly enhance tensile strength, flexural modulus, and impact resistance. Fabrication using Vacuum-Assisted Resin Transfer Molding (VARTM) and optimized GO dispersion through ultrasonication addresses challenges like GO agglomeration and fiber-matrix adhesion. Although experimental validation is pending, Theoretical predictions supported by finite element modelling (FEM) suggest significant improvements in tensile strength, flexural modulus, and impact resistance compared to neat epoxy. These composites hold promises for structural applications in aerospace, renewable energy, and automotive industries, meeting the demand for lightweight and sustainable engineering solutions.

Carbonised Typha tassel-modified enzymatic electrodes for ferrocene-mediated glucose biosensor and glucose/air biofuel cell applications

This study demonstrates the application of carbonised Typha tassel (CTT) in ferrocene-mediated enzymatic glucose biosensing and enzymatic biofuel cell (EnBFC) applications. Typha tassel was carbonised under an inert atmosphere to obtain conductive CTT which was then mixed with an effective electron transfer mediator, ferrocene (Fc) obtaining a redox-active electrode material. The successful immobilisation of the glucose oxidase (GOx) enzyme was performed on a CTT-Fc modified screen-printed electrode followed by a chitosan protective coating. The resulting enzymatic electrode was electrochemically characterised as a glucose biosensor with a working range of 0–10 mM and LOD and LOQ values of 0.19 mM and 0.56 mM, respectively. The developed glucose biosensor also showed good reproducibility and reusability with RSD% values of 6.68 % and 8.75 %, respectively. Furthermore, a real sample demonstration was performed using commercial jam samples with good recovery values. Finally, an EnBFC demonstration was performed using the enzymatic biosensor as an anode and a non-enzymatic cathode prepared using platinum black on gas diffusion carbon electrodes reaching a maximum power density of 3.6 µW cm−2. This study shows the promise of CTT as an alternative to conventional materials in enzymatic biosensor and bioelectronic applications as a suitable, cheap, and sustainable material.

Biomass-based photothermal fabrics and superhydrophobic aerogel for self-floating solar evaporators with high energy efficiency in fresh water production from seawater

In the context of global water scarcity, solar-powered seawater desalination represents a highly promising approach to addressing the freshwater crisis, offering a green and sustainable solution. However, conventional solar evaporators (SEs) often have issues such as salt deposition and heat loss by conduction, which result in decreased evaporation rates energy efficiency. Moreover, they often require the use of challenging-to-degrade polymer materials as the insulation layers and buoyancy support. In this study, we fabricated a novel energy-efficient SE capable of self-standing/self-floating with biomass materials for biodegradability and sustainability. The photothermal layer of the SE was made with waste cotton cloth modified with CuS for high hydrophilicity and photothermal conversion efficiency, with hierarchical pores for rapid water delivery to the evaporation surface. The supporting base of the SE was made biomass-based superhydrophobic aerogel to provide effective thermal insulation and self-floating ability. The novel design of the SE significantly reduced heat transfer from the top photothermal zone to the bulk water body without affecting rapid water delivery, thereby preventing salt deposition and improving energy efficiency. Under 1 light illumination, the water evaporation rate of the SE reached 2.94 kg m-2h−1 and 93 % evaporation efficiency. The water harvested via the engineered evaporation system is suitable for direct application in crop irrigation. This type of SEs may have commercial application potential in seawater desalination agricultural planting field, and wastewater treatment.

Utilization of copper slag as fine sand replacement in concrete: a response surface methodology approach

The utilization of industrial by-products in concrete production has gained significant attention due to its potential environmental and economic benefits. The increasing demand for sustainable construction materials has prompted researchers to explore alternative options that mitigate environmental concerns while maintaining desirable mechanical properties of concrete. This research paper investigates, the feasibility of utilizing copper slag as a partial replacement for fine aggregate in concrete through a systematic experimental study using response surface methodology (RSM). The study encompasses the optimization of concrete mix proportions by considering the varying levels of copper slag content (20%, 30%, and 40%), water-cement ratio (0.35, 0.40, and 0.45), and curing days (7, 14 and 28 days). Through a series of comprehensive laboratory experiments (RSM designed) and statistical analyses, this paper presents developed mathematical models, response surface plots, and contour plots and optimization of dosage of input variables for maximum compressive strength of the concrete. Results revels that curing days having strong influence on performance of compressive strength. The optimization study shows the optimal dosage for maximum performance of compressive strength was copper slag 35.90%, water-cement 0.38 and curing days 27.55 (approx. 28) days, the corresponding maximum compressive strength was 59.29 MPa. The utilization of copper slag as a replacement for fine aggregate in concrete not only addresses the issue of waste disposal but also contributes to resource conservation and reduces the carbon footprint associated with traditional construction practices.

Tailoring Synergistic Polylactic Acid–Based Nanocomposites for Sustainable Antimicrobial Fruit Packaging

ABSTRACTThe rising demand for sustainable and antimicrobial packaging materials has fuelled innovations in polymer‐based solutions, especially in the preservation of fresh fruit to reduce food waste and enhance food safety. This review delves into the advancement and refinement of nanocomposites based on polylactic acid (PLA) for sustainable antimicrobial fruit packaging, emphasising the synergistic effects of combining PLA with nanofillers and antimicrobial agents, such as metal and metal oxide nanoparticles, plant extracts and essential oils (EOs) and carbon nanomaterial. By elucidating the synergistic effects that emerge from these combinations, this review examines the ability to enhance mechanical and antibacterial properties of PLA, followed by a review of the recent changes in sustainable fruit packaging solutions that integrate technological features and environmental considerations. Ultimately, this review provides a comprehensive overview of the advancements in PLA‐based antimicrobial packaging, offering insights on the environmental benefits of integrating antimicrobial functionality into PLA‐based materials and the future of sustainable packaging for fruit preservation.

Recycling waste tiles and waste catalysts for high-strength eco-porous ceramics in building applications

This study explores an innovative approach to recycling waste tiles and spent catalytic materials from the petrochemical industry, aiming to create ecological porous ceramics (eco-PC) as sustainable building materials. The production process involved high-pressure sintering at 5 MPa and temperatures of 900–1050 °C. Extensive testing revealed that eco-PC meets CNS 9737 standards for flexural strength, with heavy metal concentrations (measured using microwave-assisted acid digestion) within regulatory limits, confirming the materials’ recyclability. The eco-PC samples exhibited water absorption between 7.90% and 35.33%, with higher sintering temperatures reducing absorption due to vitrification, while increased waste catalyst content raised absorption due to retained porosity. Porosity ranged from 16.35% to 47.42%, influenced by sintering temperature and waste catalyst content. Loss on ignition (0.14–1.63%) was affected by the decomposition of waste catalyst and sintering temperature. Flexural strength varied from 3.36 to 179.09 N/mm2, and modulus of rupture from 458 to 16,718 N, all exceeding CNS 9737 requirements. Conversely, higher catalyst content decreased strength due to limited densification of aluminum oxide. X-ray diffraction identified quartz as the primary phase, FTIR analysis showed surface functional groups (Si–O–Si and Si–O–Al), and SEM revealed a dense structure at 1050 °C due to liquid-phase sintering. Optimal eco-PC samples with 30–40% catalyst substitution and sintering temperatures of 900–1000 °C achieved a moisture buffering value (MBV) of 3.69 g/m2·%RH@8h, ideal for humidity regulation due to high surface area and pore volume. This research demonstrates the potential to transform waste into green building resources through an efficient, cost-effective, and eco-friendly process.