Bone defects are one of the most intractable problems in orthopedic clinical work. Artificial bone tissue engineering scaffolds for the treatment of bone defects have shown a significant development trend. In this study, a suitable aperture and high-porosity pore structure was prepared using a simple method. It also provided a microenvironment for nutrient and oxygen flow as well as waste discharge, which are required for cell growth, further stimulating the osteogenic differentiation of tissue cells. The poly(ε-caprolactone)/cellulose nanocrystal (PCL/CNC) two-dimensional (2D) fiber membrane (with CNC at 3
Low-cost, biomass-derived carbon aerogels have garnered significant interest as effective materials for electromagnetic wave absorption (EMWA) due to their lightweight nature and sustainability. However, the performance of pure carbon aerogels is frequently constrained by inadequate impedance matching and insufficient loss mechanisms, leading to excessive reflection. Here, we report the fabrication of hierarchically oriented carbon aerogels derived from cellulose nanofibers (CNFs) to address these challenges. The oriented aerogel backbone was first constructed using a directional ice-templating method followed by carbonization to establish a continuous conductive network. Subsequently, molybdenum disulfide (MoS2) nanoparticles were grown in situ on this carbon framework (C-CNF) via a controllable hydrothermal synthesis, forming C-CNF/MoS2 composite aerogels. This hierarchical design ensures the uniform dispersion of MoS2 microspheres, which significantly improves impedance matching and enhances dielectric loss. Furthermore, Density Functional Theory (DFT) simulations reveal that the work function difference at the C-CNF/ MoS2 heterojunction induces electron transfer, intensifying interfacial polarization as an additional mechanism for EMWA enhancement. Consequently, the optimized C-CNF/MoS2 aerogel, which integrates multiple synergistic loss mechanisms, exhibits outstanding EMWA performance, achieving a minimum reflection loss (RLmin) of –72.58 dB and a broad effective absorption bandwidth (EABmax) of 6.96 GHz. This study presents a promising strategy for developing lightweight, high-performance, cellulose-based absorbers for next-generation stealth and shielding applications.
This study investigates the development of eco-friendly bio-based polyurethane (BPU) films using castor oil (CO) and tea polyphenol (TP) as sustainable raw materials. The BPU films were synthesized via a solution casting method by reacting isophorone diisocyanate (IPDI) with CO as the renewable polyol component. BPU films were prepared via solution casting, first reacting IPDI with polyols (PCL and CO) to form a prepolymer, then chain-extending with DEG. At this ratio, the films exhibited enhanced crosslinking density, contributing to balanced strength and flexibility. Further analysis confirmed that higher CO concentrations improved resistance to water vapor transmission, making the material suitable for moisture-sensitive applications. To expand functionality, tea polyphenol (TP) was incorporated into the BPU matrix to create bioactive composites (T-BPU). FTIR and SEM analyses verified the successful integration of TP without disrupting the polymer network, while TGA data indicated maintained thermal stability. Notably, the T-BPU films also demonstrated dose-dependent antioxidant activity, scavenging 43.7
This study aimed to fabricate lightweight, eco-friendly composites and evaluate their mechanical and morphological properties. Continuous–short hybrid jute fibers were used to reinforce low-density unsaturated polyester resin (LDUPR) through the pultrusion process. Activated azodicarbonamide powder served as a foaming agent and decomposed during processing to promote matrix cell growth. A dual-initiator system comprising benzoyl peroxide (BPO) and tert-butyl peroxybenzoate (TBPB) was employed to control the curing rate and foaming of the unsaturated polyester resin (UP). The gel time analysis revealed that the sample with a TBPB: BPO ratio of 1.75:0.25 presented the lowest curing peak temperature and the longest gel time. Conversely, the sample with a 1:1 initiator ratio had the highest curing rate, indicating that BPO is a more effective initiator for resin curing than TBPB is. Mechanical testing demonstrated that reducing the continuous fiber volume fraction from 80
This research paper presents a significant advancement in the field of bone tissue engineering through the development of biodegradable three-dimensional scaffolds fabricated using three-dimensional (3D) printing technology. Poly-caprolactone (PCL) was employed as the base polymer to create the scaffolds, into which zinc oxide (ZnO) nanoparticles were incorporated at different concentrations to enhance antibacterial activity and mechanical performance. The printed scaffolds were subsequently coated with a collagen–magnesium (Mg) composite to improve hydrophilicity, biocompatibility, and drug-release behavior. Comprehensive characterization was carried out, including SEM, FTIR, swelling, degradation, mechanical testing, and biological evaluations. The morphological analysis revealed well-defined and uniformly printed strands with an approximate diameter of 0.3 mm. Mechanical tests showed that the elastic modulus of the fabricated scaffolds increased from 35 ± 3 MPa for the PCL control scaffold to 47 ± 3 MPa for the PCL/Mg scaffold, indicating improved stiffness and an approach toward the lower range of native cancellous bone. Drug-release studies demonstrated a controlled and sustained magnesium release over 25 h, while biocompatibility assessments indicated excellent cell viability, reaching 100
The effect of modified sawdust (SD) on the properties of plasticized polylactic acid/natural rubber (P-PLA/NR) thermoplastic natural rubber composites was studied in relation to food contact applications. Although SD incorporation increased Young’s modulus, other mechanical properties decreased, likely due to the polarity difference between the hydrophilic filler and the hydrophobic polymer matrix. Because chemical modifiers have varied effectiveness at reducing the polarity of cellulose-based fillers, a comparative approach was employed to identify the most suitable treatment. Specifically, triacetate-modified SD was evaluated via anhydride (AA), vinyltriethoxysilane (VTES), and aminopropyltriethoxysilane (APTES). Fourier transform infrared (FTIR) spectral and surface tension analyses confirmed that triacetate modification reduced SD hydrophilicity most effectively. Among the tested formulations, the composite with a P-PLA/NR/triacetate-SD weight ratio of 90/10/25 containing triacetate-modified SD exhibited the best performance, with elongation-at-break and toughness increased by approximately 41
Electrospun twisted yarns have higher mechanical strength than non-woven webs, making them more suitable for biomedical applications, though further improvement is still required. This study investigates the influence of uniaxial drawing post-treatment on the drug release performance of electrospun poly(L-lactic acid) (PLLA) nanofibrous yarns incorporated with graphene oxide (GO) and loaded with vancomycin (Vanc) as a model drug. Utilizing a double-nozzle electrospinning technique, the composite yarns were produced and subjected to uniaxial drawing process at various extension ratios. The results indicated that uniaxial drawing effectively reduced fiber and yarn diameters, improved alignment, and increased mechanical strength to 45
The aim of this experimental work was to investigate the combined effects of mechanical loading conditions and temperature on possible structural defects in bilayer polymer sheets. The studied sheets were obtained by coextrusion of an acrylonitrile–butadiene–styrene (ABS) layer and a 15
The present work examines the properties of polylactic acid (PLA) blended separately with thermoplastic polyurethane (TPU), polyethylene vinyl acetate (EVA), and polybutylene adipate terephthalate (PBAT) in a 70/30 weight ratio and compares them. The PLA blends were prepared using melt blending technique. Results indicate that significant differences were observed in the performance of these blends based on the minor portion of the polymer used. Furthermore, to alter the dispersion level and improve the blend properties, nanoclay was added at 3, 5, and 7 parts (parts per hundred resin), and their thermal and mechanical properties were analysed. Thermogravimetric analysis (TGA) and the activation energy calculated based on kinetic studies show that all three individual blends without nanoclay have lower thermal stability than neat PLA. After the addition of nanoclay to the blend, the activation energy increased from 76 to 84.5 kJ/mol for PLA/TPU and from 83 to 92 kJ/mol for PLA/EVA at a nanoclay composition of 7 parts, compared with the neat blends. PLA/TPU based blends and nanocomposites show higher elongation, with 31
This study reports the development of sustainable multiscale epoxy hybrid composites reinforced with Ca(OH)2-treated bamboo fibers, glass fibers, and multi-walled carbon nanotubes (MWCNTs) for simultaneous enhancement of mechanical performance, fracture resistance, thermal stability, and flame retardancy. A combined response surface methodology (RSM) and artificial neural network (ANN) framework was employed to optimize the interactions among Ca(OH)2 treatment concentration, MWCNT loading, and bamboo-fiber content. Among the investigated Ca(OH)2 concentrations (1–9 wt
The assessment of the mechanical properties and wear behavior of 3D-printed polyethylene terephthalate glycol (PETG) and carbon fibre (CF)-reinforced composite was established at different applied load and sliding speed. The present study investigates the individual effect of carbon fiber reinforcement on tensile, flexural, impact, hardness and wear test. Thermoplastic PETG reinforced with carbon fibers exhibits remarkable enhancement in terms of mechanical characteristics. This includes an amazing increase of 50
This study focuses on the fabrication, and characterization of sustainable hybrid epoxy sandwich composites reinforced with jamun seed powder (JSP), bamboo cotton cloth (BCC), and E-glass fibre (EGF). Four composite systems were developed: neat epoxy (E), epoxy with JSP (JSPEC), epoxy with JSP and BCC (JSPBCREC), and epoxy with JSP, BCC, and EGF (JSPBCLEFREC). Mechanical characterization revealed significant improvements in tensile, compressive, flexural, and hardness properties with the incorporation of reinforcements. The tensile strength increased from 34.27 MPa for neat epoxy to 132.34 MPa for JSPBCLEFREC, representing a 286
The widespread application of nanofiltration (NF) membranes in desalination is still limited by the inherent permeability–selectivity trade-off and severe membrane fouling, which reduce operational efficiency and membrane lifespan. In this study, a sustainable solution is proposed by employing a bio-based biosurfactant as a surface modifier to enhance both separation performance and antifouling behavior of thin-film composite polysulfone (TFC-PSf) NF membranes. The membranes were fabricated via phase inversion followed by interfacial polymerization and modified with a biosurfactant produced by Bacillus subtilis ATCC 6633 at concentrations of 0.05, 0.1, and 0.2 wt
Composites are developed by incorporating different weight percentages (10, 20, 30, 40, and 50) of water-melon seed powder (WSP) into high-density polyethylene (HDPE) through an injection molding process. The FTIR (Fourier transform infrared spectroscopy), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) were carried out to determine the presence of functional groups, crystal size, melting point, and thermal degradation of the composites. The FTIR analysis revealed the presence of functional groups such as −OH, N−H, C=C, and C−Br in the 30
Poly(lactic acid) (PLA) is brittle with a low elongation-at-break, severely limiting its applications. To address this challenge, we synthesized a novel furan‑based copolyester, poly(ethylene furanoate‑co‑dodecylene furanoate) (PEDF), containing rigid furan rings for strength retention and long dodecylene segments for flexibility, and melt‑blended it with PLA to effectively improve ductility with high tensile strength. The results confirmed that the high molecular weight random copolymer PEDF was successfully synthesized. DSC and DMA tests indicate that the introduction of PEDF can reduce the glass transition temperature of PLA and enhance its molecular chain mobility. The tensile test shows that the elongation-at-break of PEDF is as high as 1033.6
Chitosan, a versatile biopolymer, can be extracted from chitin, which is predominantly present in silkworm pupae waste. Chitosan was extracted from silkworm pupae via defatting with n-hexane, demineralisation with dilute HCl, deproteination with NaOH, and deacetylation by alkali treatment. The extracted chitosan’s functional group was compared with that of commercially available chitosan. The crystallinity index of the silkworm pupae chitosan was 31.2
Curing deformation is a typical challenge that troubles the precise molding of carbon fiber reinforced plastics (CFRP) box structure, and the curing process parameters are the key factors affecting curing deformation. In this study, a multi-physics finite element simulation model incorporating thermal-chemical reactions, curing kinetics and residual stress, is established for simulating the molding process of CFRP box structure. The effects of curing process parameters such as heating rate, holding temperature and time, cooling rate, and curing pressure on the curing temperature field, curing degree, and residual stress are systematically analyzed. Based on the simulation results, a three-factor and three-level orthogonal experiment is designed and conducted to establish a response surface model for the residual stress and demolding deformation after curing. The results indicate that the cooling rate has a more significant impact on the curing behavior of the CFRP box structure compared to other curing process parameters. When the cooling rate is increased to 3.5 °C/min, the residual stress of the CFRP box structure rises by 0.27
Addressing the critical need for mass-efficient safety structures in transportation, this work introduces a novel class of 3D-printed lightweight metamaterials engineered for automotive seat frames. Through a synergistic experimental and computational approach, this study establishes a comprehensive design framework that links unit-cell geometry specifically thickness and width, to macroscopic performance. The metamaterial exhibits a highly tunable stiffness (141–147 N/mm) and peak load (24–305 N), enabling customized structural support. Its most distinguishing feature is an exceptional specific energy absorption (SEA) capacity, reaching 2200 mJ/g, which stems from a controlled auxetic collapse mechanism characterized by the predictable evolution of soft-mode instabilities. The force-displacement response demonstrates a nonlinear regime with progressive stiffness degradation following initial linear elasticity, a behavior sometimes described in the literature as reverse hardening. Finite element analysis, validated within 4
Environmental pollution represents one of the main challenges of the modern era, profoundly impacting daily life, public health, and ecological systems. Among the various pollutants, plastic waste—particularly non-biodegradable polymers—contributes significantly to long-term environmental degradation, including the contamination of water bodies, soil, and food chains. In this context, recycling synthetic polymers, especially those that are not easily recyclable through conventional mechanical methods, is essential. This research focuses on the chemical recycling of PET (polyethylene terephthalate), a widely used polymer in packaging and textiles, through glycolysis to produce the BHET (bis(hydroxyethyl) terephthalate) monomer. Successful depolymerization was confirmed through FTIR analysis, which verified the formation of the BHET monomer. Subsequently, the recovered BHET was utilized as a key reactant to synthesize PBAT (poly(butylene adipate-co-terephthalate)), a biodegradable polyester known for its potential to replace conventional plastics in various applications. The synthesis of PBAT was achieved via melt polymerization, and the resulting polymer was thoroughly characterized using multiple analytical techniques, including FTIR, NMR, TGA, DSC, and viscometry. The FTIR spectrum exhibited characteristic absorption peaks at 2955.11, 1727.83, 1272.69, 1122.19, and 731.53 cm⁻¹, confirming the successful formation of PBAT. NMR and DSC results further corroborated the chemical structure and thermal properties of the synthesized polymer. Importantly, the molecular weight of the final product was determined to be 44,355.85 g/mol, affirming the successful formation of a high-molecular-weight polymer. This study underscores the viability of recycling PET waste into high-value biodegradable polymers, thereby contributing meaningfully to environmental sustainability and the circular economy.
