Search Results (222)

Melt-spun PA6/TiO₂ fibers with TiO₂ modified by silane coupling agents KH550 and KH570 at 0, 1.6, and 4 wt% provide a practical testbed to address three fiber-centric gaps: transferable interphase quantification, interphase-resolved indications of compatibility, and a reproducible kinetics–structure–property link. This work proposes, for the first time at fiber scale, a four-phase partition into crystal (c), crystal-adjacent rigid amorphous fraction (RAF-c), interfacial rigid amorphous fraction (RAF-i), and mobile amorphous fraction (MAF), and extracts an interfacial triad consisting of the specific interfacial area (S_v), polymer-only RAF-i fraction expressed per composite volume (Γ_i), and interphase thickness (t_i) from SAXS invariants to establish a quantitative interphase-structure–property framework. A documented SAXS/DSC/WAXS workflow partitions the polymer into the above four components on a polymer-only basis. Upon filling, Γ_i increases while RAF-c decreases, leaving the total RAF approximately conserved. Under identical cooling, DSC shows the crystallization peak temperature is higher by 1.6–4.3 °C and has longer half-times, indicating enhanced heterogeneous nucleation together with growth are increasingly limited by interphase confinement. At 4 wt% loading, KH570-modified fibers versus KH550-modified fibers exhibit higher α-phase orientation (Hermans factor f(α): 0.697 vs. 0.414) but an ~89.4% lower α/γ ratio. At the macroscale, compared to pure (neat) PA6, 4 wt% KH550- and KH570-modified fibers show tenacity enhancements of ~9.5% and ~33.3%, with elongation decreased by ~31–68%. These trends reflect orientation-driven stiffening accompanied by a reduction in the mobile amorphous fraction and stronger interphase constraints on chain mobility. Knitted fabrics achieve a UV protection factor (UPF) of at least 50, whereas pure PA6 fabrics show only ~5.0, corresponding to ≥16-fold improvement. Taken together, the SAXS-derived descriptors (S_v, Γ_i, t_i) provide transferable interphase quantification and, together with WAXS and DSC, yield a reproducible link from interfacial geometry to kinetics, structure, and properties, revealing two limiting regimes—orientation-dominated and phase-fraction-dominated. Full article

Herein, we report a combined computational and experimental investigation into the recently reported universal pyrazole-based reversible addition-fragmentation chain transfer (RAFT) agents (Z−C(=S)−S−R, where Z is 3,5-dimethyl-1H-pyrazol-1-yl), which can mediate controlled radical polymerization of a broad scope of monomers without the need for an additional initiator or catalyst. The results reveal that the high molar absorption coefficient and efficient photolysis kinetics of pyrazole-based chain transfer agents (CTAs) under blue light (${\lambda }_{\max }$ = 465 nm) enable rapid radical generation, underpinning ultrafast polymerization of acrylates, acrylamides, methacrylates, and N-vinylpyrrolidone (NVP). While the efficient light absorption is attributed to structural dissimilarity between the Z group and the S–R group (which breaks the local symmetry of the C=S group), the fast photolysis originates from favorable $\pi$ electron donation from the Z group to the C=S group. Meanwhile, the $\pi$ electron donation is still weaker than in xanthates, which explains the excellent control of a wide range of monomers, except methacrylates. This work establishes design principles for next-generation CTAs for ultrafast and monomer-universal photoiniferter RAFT polymerization. Full article

Phages are considered effective biocontrol agents for improving food safety due to their specific interaction with pathogens. It is essential to recognise that zero risk does not exist, and as biological agents, phages must be continuously evaluated for potential adverse effects on human health in both food and clinical contexts. This is the first bacteriophage risk profile performed according to the methodology recommended by FAO/WHO and EFSA. Key safety concerns regarding phage use in the food sector include the risk of horizontal gene transfer, especially regarding antibiotic resistance genes among bacteria. While such occurrences are contextually dependent and rare, they warrant further scrutiny. Moreover, improper phage application during food processing could lead to the emergence of resistant bacterial strains, compromising the long-term efficacy of phage interventions. Currently, there is limited evidence indicating any health risks linked to phage consumption or pathogenic behaviour (e.g., possible association between bacteriophages and Parkinson’s disease). Despite numerous studies affirming the safety and efficacy of phages in the food chain, continuous monitoring remains crucial. In particular, the responses of susceptible populations to phage exposure should be carefully examined. Full article

Modular integrated construction (MiC) is a cutting-edge approach to construction that significantly improves efficiency and reduces project timelines by prefabricating entire building modules off-site. Despite the operational benefits of MiC, the carbon footprint of its extensive supply chain remains understudied. This study develops a hybrid approach that combines multi-agent simulation (MAS) with deep learning to provide scenario-based estimations of CO₂ emissions, costs, and schedule performance for MiC supply chain. First, we build an MAS model of the MiC supply chain in AnyLogic, representing suppliers, the prefabrication plant, road transport fleets, and the destination site as autonomous agents. Each agent incorporates activity data and emission factors specific to the process. This enables us to translate each movement, including prefabricated components of construction deliveries, module transfers, and module assembly, into kilograms of CO₂ equivalent. We generate 23,000 scenarios for vehicle allocations using the multi-agent model and estimate three key performance indicators (KPIs): cumulative carbon footprint, logistics cost, and project completion time. Then, we train artificial neural network and statistical regression machine learning algorithms to captures the non-linear interactions between fleet allocation decisions and project outcomes. Once trained, the models are used to determine optimal fleet allocation strategies that minimize the carbon footprint, the completion time, and the total cost. The approach can be readily adapted to different MiC configurations and can be extended to include supply chain, production, and assembly disruptions. Full article

Innovative demand-responsive transport services are spreading in most urban areas, allowing dynamic matching between demand and supply and enabling travellers to request shared rides in real-time via mobile applications. They are used both as an alternative to public transport and as an access/egress leg to mass transit stations, i.e., acting as a feeder service. In low-demand areas and small-sized cities, it is often difficult to provide effective and cost-efficient public transport, thus resulting in an extensive use of private vehicles. Using an agent-based modelling approach, this study compares the performance of fixed-route transit (FRT) and demand-responsive transit (DRT), where optional stops can be activated on demand. The aim is to identify the conditions allowing DRT to become more advantageous than FRT in small-sized cities, both for travellers and the transport operator. A real-time matching algorithm identifies optimal trip chains (i.e., public transport lines; pick-up, drop-off and transfer stops; and time windows) for travel requests, dynamically updating vehicles’ routes and schedules. The model is applied to the city of Caltanissetta, Italy, where a transit service with six FRT urban lines is currently operating. Travel patterns were reconstructed from thousands of travel requests collected by a Mobility-as-a-Service platform within one-year. The main findings demonstrate the benefits of DRT in providing a higher quality of service, reducing riding times for passengers, and enhancing service efficiency without burdening operating costs. The DRT reduced the vehicle-kilometres travelled by up to 5% compared to FRT while decreasing passenger ride times by approximately 10%. An economic analysis showed reductions in operator unit costs of up to 3.4% for low-demand rates, confirming the advantages of flexible operations in small-sized cities. Full article

Silylation treatment improves the hydrophobicity of cellulose by reducing the number of hydroxyl groups in the cellulose chains that are available to react with moisture in the surrounding environment. Additionally, silylation increases stress transfer from cellulose to synthetic nanofillers by forming covalent bonds between the hydroxyl groups of cellulose and the oxidized surface of these nanofillers. This study investigates the impact of silane coupling agents on the tensile properties of cellulose nanocomposites. The cellulose nanocomposites are reinforced with four types of C/SiC-based nanofillers: carbon nanotubes, graphene nanoplatelets, silicon carbide nanotubes, and silicon carbide nanoplatelets. Subsequently, the nanofillers are subjected to surface treatment using the silane coupling agent KH550. The mechanical properties of the cellulose nanocomposites are evaluated by molecular dynamics simulations based on the polymer’s consistent forcefield. The results indicate that the reinforcements of silylated silicon carbide nanotubes and carbon nanotubes increase the tensile modulus of cellulose by 18.03% and 24.58%, respectively, compared to their untreated counterparts. Furthermore, the application of silylation treatment on the surface of C/SiC nanofillers increases the yield strength and ultimate tensile strength of cellulose nanocomposites due to enhanced load transfer between cellulose and these reinforcements. Full article

Poly (styrene-maleic anhydride) copolymers, due to their unique structure, are extensively functionalized and modified for preparing heat stabilizers, compatibilizers, and other functional additives. Using 4-methylpent-1-ene-2,4-diyl diphenyl (α-MSD) as a chain transfer agent, a series of molecular-weight-controlled maleic anhydride-derived styrene copolymers, poly(N-p-fluorophenylmaleimide-alt-styrene) (PFS) and poly(N-p-carboxylphenylmaleimide-alt-styrene) (PCS), were synthesized via free radical copolymerization. The molecular weights of PFS and PCS were adjusted to explore their impact on the properties of PFS/PA6 and PCS/PA6 blends. Gel permeation chromatography (GPC) analysis confirmed that α-MSD effectively regulated the molecular weights of PFS and PCS. PFS and PCS with lower molecular weights exhibited significantly reduced viscosity, with minimal impact on their thermal and mechanical properties. Full article

Novel amphiphilic block copolymers of N-vinyl pyrrolidone (NVP) and either n-hexyl methacrylate (HMA, PNVP-b-PHMA) or stearyl methacrylate (SMA, PNVP-b-PSMA) were prepared by RAFT polymerization techniques and the sequential addition of monomers starting from the polymerization of NVP and using two different Chain Transfer Agents, CTAs. PNVP-b-PHMA are amorphous block copolymers containing constituent blocks with both high and low Tg values, whereas PNVP-b-PSMA are amorphous–semi-crystalline copolymers. Samples with different molecular weights and compositions were obtained. The copolymers were microphase-separated, but partial mixing was also observed. The presence of the amorphous PNVP block reduced the crystallinity of the PSMA blocks in the PNVP-b-PSMA copolymers. The thermal stability of the blocks was influenced by both constituents. The self-assembly behavior in THF, which is a selective solvent for polymethacrylate blocks, and in aqueous solutions, where PNVP was soluble, was examined. Unimolecular or low-aggregation-number micelles were obtained in THF for both types of samples. On the contrary, high-aggregation-number, spherical, and compact micelles were revealed in aqueous solutions. The increase in the steric hindrance of the side ester group of the polymethacrylate chain led to slightly lower degrees of association. The hydrophobic compound curcumin was efficiently encapsulated within the micellar core of the supramolecular structures in aqueous solutions. Micelles with higher aggregation numbers were more efficient in the encapsulation of curcumin. The results of this study were compared with those obtained from other block copolymers based on PNVP. Full article

Polyacrylonitrile (PAN) is renowned for its excellent physical and chemical properties, making it a promising candidate for producing high-performance and energetic materials. However, traditional high-molecular-weight PAN suffers from poor solubility and low reactivity, which limits its application as a precursor for advanced materials. To overcome these issues, this study successfully synthesized low-molecular-weight PAN (M_η: 6.808 kDa) using an environmentally friendly aqueous precipitation polymerization method, utilizing ammonium persulfate (6 wt% relative to the monomer mass) as the initiator and isopropanol (400 wt%) as the chain transfer agent. The structures and properties of the synthesized low-molecular-weight PAN were analyzed in depth. The morphology and chain structure of PAN were characterized using field-emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FT-IR), and nuclear magnetic resonance hydrogen spectroscopy (¹H NMR). The thermal properties were assessed using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Additionally, the state changes during the heating process of PAN with different molecular weights were directly observed using a visual melting point analyzer for the first time. Furthermore, the influence of molecular weight on PAN’s solubility was investigated in detail. Based on that, a linear regression between the viscosity average molecular weight (M_η) and the number average molecular weight (M_n) was established, providing simple and rapid access to the molecular weight of the synthesized PAN via viscosity measurements. Our study employed CTA-controlled aqueous precipitation polymerization to prepare low-molecular-weight PAN, which possesses significant potential in producing tetrazole-based energetic materials. Full article

In this study, novel triblock copolymers, including poly(N-isopropylacrylamide)-block-poly(ε-caprolactone)-block-poly(N-isopropylacrylamide) (PNIPAM-b-PCL-b-PNIPAM), poly(N-vinyl-pyrrolidone)-block-poly(ε-caprolactone)-block-poly(N-vinyl-pyrrolidone) (PNVP-b-PCL-b-PNVP), poly(N-isopropylacrylamide-co-N,N-dimethylaminoethyl methacrylate)-block-poly(ε-caprolactone)-block-poly(N-isopropylacrylamide-co-N,N-dimethylaminoethyl methacrylate) (P(DMAEMA-co-NIPAM)-b-PCL-b-P(NIPAM-co-DMAEMA)), and poly(N,N-dimethylacrylamide)-block-poly(ε-caprolactone)-block-poly(N,N-dimethylacrylamide) (PDMA-b-PCL-b-PDMA), were synthesized via a combination of ring-opening polymerization (ROP) and reversible addition–fragmentation chain transfer (RAFT) polymerization. The synthesis was performed using novel bifunctional PCL-based RAFT macro chain transfer agents (macroCTAs; MXTPCL-X1 and MXTPCL-X2) with a m-xylene-bis(2-mercaptoethyloxy) core. Initially, m-xylene-bis(1-hydroxy-3-thia-propane) (MXTOH), which has not previously been used in lactone polymerization, was synthesized via the reaction of α,α′-dibromo-m-xylene with 2-mercaptoethanol in the presence of sodium in ethanol. Subsequently, Sn(Oct)₂-catalyzed ROP of ε-caprolactone (ε-CL) using MXTOH as an initiator yielded PCL-diol (MXTPCLOH). The resulting PCL-diol underwent further functionalization through esterification and substitution reactions, leading to the formation of PCL-based RAFT macroCTAs. Triblock copolymers were synthesized using these macroCTAs with AIBN as an initiator. The synthesized products, along with their intermediates, were characterized using FTIR and ¹H NMR spectroscopy. The number average molecular weight (M_n) and polydispersity index (Ð) of PCL-based macroCTAs were determined by using GPC analysis. The sensor capabilities of the synthesized novel triblock copolymers were investigated on the determination of syringic acid and it was determined that the most sensitive polymer was PNVP-b-PCL-b-PNVP (MXTP2). The working range was between 1.5 µg/mL and 15 µg/mL and the limit of detection (LOD) was found to be 0.44 µg/mL using DPV on MXTP2 polymer sensor. Full article

In this project, a new class of temperature- and pH-sensitive hydrogel consisting of N-isopropyl acrylamide (NIPAM), hydroxyethyl methacrylate (HEMA), and acrylamide (AAm) was prepared via a controlled route through the reversible addition–fragmentation chain-transfer (RAFT) polymerization process. Poly(ethyleneglycol) dimethacrylate (PEG-DMA) was used as a long-chain hydrophilic and biocompatible crosslinking agent. The hydrogel structure was confirmed by different characteristic techniques such as ¹H NMR, FT-IR, and SEC, and the morphology and particle diameters were checked via the scanning electron microscopy (SEM) and dynamic light scattering (DLS) methods. Afterward, the as-prepared hydrogel, poly(NIPAM-co-HEMA-co-AAm), was loaded with doxorubicin (DOX) to be used as a temperature- and pH-triggered delivery carrier. The prepared system released DOX slowly at 37 °C and neutral pH, but increased DOX release significantly at 42 °C and acidic pH. The anti-cancer efficiencies of free DOX, hydrogel, and the DOX–hydrogel conjugate were tested in vitro using human colorectal adenocarcinoma HT-29 cell lines. Cytotoxicity evaluation of free DOX compared with the DOX–hydrogel conjugate revealed that more cancer cells were killed with increasing concentration. Moreover, the DOX-mediated apoptosis and ROS levels showed the beneficial effects of poly(NIPAM-co-HEMA-co-AAm) hydrogel for cancer drug delivery. Generally, the results suggest that this system can be a potential candidate for designing drug delivery systems. Full article

Microplastic contamination is rapidly becoming an increasingly worrying environmental problem and poses a real threat to marine ecosystems and human health. The aim of this research was to conduct a traditional review of the current state of the art regarding the sources of MPs in marine environment, including an assessment of their toxic effect on marine organisms and transfer within the food webs and up to humans. An extensive literature search (from 1 January 2024 to 15 February 2025) yielded a total of 1027 primary research articles on this topic. This overview revealed that MPs can be ingested by marine organisms, migrate through the intestinal wall, and spread to other organs. They can biomagnify along the food chain and can be carriers of toxic chemicals and pathogen agents. Exposure of marine organisms to MPs can lead to several risks, including tissue damage, oxidative stress, and changes in immune-related gene expression, neurotoxicity, growth retardation, and behavioural abnormalities. The toxicity of MPs depends mainly on the particle size distribution and composition/characteristics of the polymer. The main routes of human exposure to MPs have been identified as ingestion (mainly seafood), inhalation, and dermal exposure. There is strong evidence of contamination of seafood by MPs, which pose a potential risk to human health. This study provides the basis for assessing MPs’ risk to marine ecosystems and potential human health impacts. Full article

Bacteriophages, first discovered in 1915, have re-emerged as critical players in microbial ecosystems, particularly in food production. Their ability to lysogenize bacterial hosts raises concerns about their role in the horizontal transfer of antibiotic resistance genes (ARGs) and virulence factors, contributing to the global challenge of antimicrobial resistance. Key studies reveal that ARG-carrying phages are prevalent across various stages of the food chain, including soil, vegetables, meat, dairy, and wastewater associated with food production. These findings demonstrate the potential for lysogenic phages to act as vectors for resistance gene dissemination, posing risks to public health. The review also explores emerging genetic elements, such as phage-inducible chromosomal islands and gene transfer agents, that further enhance the mobility of resistance and virulence genes. Advancements in metagenomic tools have improved our understanding of phage-mediated gene transfer, but significant knowledge gaps remain. Future research should aim to quantify these processes in real-world settings and develop strategies to mitigate the risks associated with lysogenic phages in food systems. Full article

Porous polymer membranes with highly interconnected open-cellular structure and high toughness are crucial for various application fields. Polymerized high internal phase emulsions (polyHIPEs), which usually exist as monoliths, possess the advantages of high porosity and good connectivity. However, it is difficult to prepare membranes due to brittleness and easy pulverization. Copolymerizing acrylate soft monomers can effectively improve the toughness of polyHIPEs, but it is easy to cause emulsion instability and pore collapse. In this paper, stable HIPEs with a high content of butyl acrylate (41.7 mol% to 75 mol% based on monomers) can be obtained by using a composite emulsifier (30 wt.% based on monomers) consisting of Span80/DDBSS (9/2 in molar ratio) and adding 0.12 mol·L⁻¹ CaCl₂ according to aqueous phase concentration. On this basis, polyHIPE membranes with high open-cellular extent and high toughness are firstly prepared via reversible addition–fragmentation chain transfer (RAFT) polymerization. The addition of the RAFT agent significantly improves the mechanical properties of polyHIPE membranes without affecting open-cellular structure. The toughness of polyHIPE membranes prepared by RAFT polymerization is significantly enhanced compared with conventional free radical polymerization. When the molar ratio of butyl acrylate/styrene/divinylbenzene is 7/4/1, the polyHIPE membrane prepared by RAFT polymerization presents plastic deformation during the tensile test. The toughness modulus reaches 93.04 ± 12.28 kJ·m⁻³ while the open-cellular extent reaches 92.35%, and it also has excellent thermal stability. Full article

Cadmium (Cd) pollution in farmland soil leads to excessive Cd in vegetables, which can be transferred to humans through the food chain, posing a significant threat to human health, and requires urgent measures to combat it. Modified biochar may have the potential to remediate Cd pollution in farmland soils. In this experiment, bulk biochar (YC) derived from reed straw or modified biochar by ball milling (Q) either alone or combined with a combination of several passivation agents {potassium hydroxide (K), attapulgite (A), calcium magnesium phosphate fertilizer (M), and polyacrylamide (P)} was applied to soils polluted with Cd, to investigate the growth, yield, and quality of pakchoi (Brassica chinensis L.). The results showed that bulk biochar (YC) provided pakchoi with plenty of nitrogen, phosphorus, and potassium, while passivation agents enhance macronutrient accumulation. Compared to YC, modified biochar improved pakchoi yields and nutritional quality. Among them, concentrations of nitrates in pakchoi significantly decreased by 51.8% and 51.0%, while vitamin C levels increased by 29.6% and 19.0%, respectively, in QKAMP and QKAM treatments. The contents of Cd in pakchoi significantly decreased by 21.6% and 18.6%, respectively, in QKAMP and QKAM treatments. The implementation of QKAMP led to the cadmium contents in edible vegetables being lower than the maximum stipulated content as defined by the national standard, but QKAM failed to accomplish it. In conclusion, QKAMP effectively reduced the bioavailability of Cd in the middle to slightly Cd-polluted alkaline soils, making it a suitable soil amendment to improve the yield and quality and mitigate Cd accumulation in vegetables. Full article