Despite growing concerns about microplastic (MP) contamination in Antarctic environments, polymer-resolved evaluations of MP exposure in Antarctic krill (Euphausia superba) remain limited, particularly with respect to spatial and size-specific variability. This study analyzed MP abundance, polymer composition, and exposure profiles in krill collected from two regions of the Antarctic Peninsula-the Bransfield Strait and the South Orkney Islands-by categorizing individuals into large (≥50mm) and small groups (<50mm) based on body length. MPs were detected in most samples, and MP abundance did not differ significantly between regions and remained within the range previously reported for the Southern Ocean. However, abundance was higher in the large group than in the small group. Polymer composition differed by both region and size class. Ethylene-vinyl acetate (EVA) was detected exclusively in smaller individuals, indicating size-dependent variation in ingested polymer types. Regional differences in polymer assemblages were reflected in distinct polymer hazard index (PHI) values despite modest variation in MP abundance, suggesting that derived hazard profiles were structured primarily by polymer composition rather than particle counts. This study characterizes polymer-specific MP exposure across regional and size gradients in Antarctic krill and clarifies compositional patterns that are not evident from abundance metrics alone, providing context for interpreting MP exposure within Antarctic food webs.

The development of smart materials that can react to external stimuli and provide controlled and frequently reversible responses is facilitated by the coupling of physical effects. In this work, a photo-pyroelectric effect based on a piezoelectric polyvinylidene fluoride-trifluoroethylene (P(VDF-TrFE)) polymer composite with fullerene C 60 incorporated at different concentrations (1, 3, 5, 10 and 20% wt.) has been developed with the aim of obtaining a multi responsive material: together with the piezoelectric and pyroelectric characteristics of the polymer, the inclusion of the fillers allow a photo-pyroelectric response, suitable for optoelectronic applications. The addition of fullerene – C 60 leads to a mechanical plasticizing effect in the polymer matrix, revealed by the decrease of the Young’s Modulus from 335 MPa to 157 MPa and an increase in the dielectric constant from approximately 10 to 20 at 100 Hz, for P(VDF-TrFE) samples with 20% wt. of fullerene – C 60 . A pyroelectric coefficient of 20 μC/m 2 ·K was achieved with a 10% wt. fullerene – C 60 loading, while maintaining a piezoelectric response of 15 pC/N. Further, under laser irradiation and due to the photo-pyroelectric response, the composite with 10% wt. fullerene – C 60 content reaches a generated voltage of 400 mV across a temperature variation of 1.4 °C, proving the multifunctionality of the materials and their applicability in applications including infrared detectors, thermometers, or energy harvesting, among others. A new photo-pyroelectric effect in a piezoelectric composite composed of Fullerene-C60 and the ferroelectric polymer P (VDF-TrFE) is presented. The material allows to directly produce an electric signal from light absorption through to this phenomenon, which offers a novel mechanism for optoelectronic energy conversion. Further, the material maintains its piezoelectric response, allowing for multifunctional mechano-electric, pyro-electric and photo-pyroelectric response. The photo-pyroelectric effect is enabled and improved by the polymer and fullerene's synergistic interaction, which is a crucial step in the development of high sensitive flexible photonic devices. • Photo-pyroelectric effect was demonstrated in piezoelectric and pyroelectric polymer composites of P(VDF-TrFE) with fullerene. • The influence of fullerene content on P(VDF-TrFE) was evaluated. • The mechanical, dielectric and piezoelectric properties are affected by the fullerene content. • A maximum pyroelectric coefficient of 20 μC/m 2 ·K was achieved with a 10% wt. fullerene – C60. • These composites are suitable for advanced applications with a generated voltage of 400 mV across a temperature variation of 1.4 °C.

• Study of coupling between mechanical stress relaxation and electrical resistance behavior in flexible composites. • CNTs fillers reinforcing PVDF exhibit piezoresistive response without key mechanical impact. • Temperature critically affects the mechanical relaxation of PVDF, exhibiting slight impact on resistance behavior. • Under cyclic load-unloading force, the piezoresistive performance depends on temperature. Flexible piezoresistive sensors based on polymer composites are promising for real-time monitoring applications due to their mechanical flexibility, electrical sensitivity and capability of being processed by additive manufacturing. Despite its interest, the important issue of mechanical and electrical relaxation over time, influencing sensor performance, has not been properly addressed. In this study, poly(vinylidene fluoride) (PVDF) composites reinforced with 0.5 wt% carbon nanotubes (CNTs), with proven piezoresistive characteristics, have been evaluated under mechanical and electromechanical loading at various temperatures (room temperature to 100 °C). The study aimed to evaluate the coupling between mechanical stress relaxation and electrical resistance behavior under constant strain conditions. While mechanical stress exhibited significant viscoelastic decay, from ≈33 to ≈6 MPa at 5% strain and 100 °C during 1800 s, electrical resistance remained remarkably stable, fluctuating by less than 5% across most conditions. Cyclic deformation tests further confirmed this electrical stability under repeated loading. These results reveal a decoupled electromechanical response with respect to relaxation dynamics, suggesting that CNT networks near the percolation threshold remain largely unaffected by polymer matrix relaxation.

Microplastics in high-mountain air at the Altzomoni Observatory, Mexico: evidence of regional transport shaped by boundary layer dynamics.

From beaches to mangroves: Spatiotemporal mapping and risk profiling of microplastics in coastal Bangladesh.

Size- and polymer-dependent effects of polystyrene and polyethylene micro- and nanoplastics in zebrafish (Danio rerio).

Microplastics in human semen: Physicochemical characterisation and surface-associated elemental profiles among Malaysian men.

Load redistribution around a single fibre break is a critical mechanism determining longitudinal tensile strength in carbon fibre-reinforced polymer (CFRP) composites, with understanding of this process historically relying on model predictions. Digital Volume Correlation (DVC) combined with high-resolution computed tomography has previously enabled the experimental quantification of strains around fibre breaks, using volumetric speckle patterns generated by the addition of fiducial particles to the composite matrix. Applying fiducial particles to CFRP to interrogate the length scales of single fibre breaks is non-trivial, as micrometre-scale inhomogeneity and particle agglomeration may compromise the broader applicability of the results. The present study extends the potential applicability of DVC, in combination with synchrotron computed tomography, by incorporating silicon dioxide (SiO 2 ) particles into CFRPs as a practical and improved alternative to barium titanate (BaTiO 3 ) particles used in previous work. The applicability is assessed in terms of particle distribution, DVC measurement uncertainty, and strain recovery lengths around single fibre breaks. The assessments reveal that SiO 2 particles can produce a reasonably uniformly dispersed speckle patterns with minimal apparent agglomeration, providing the fidelity required for accurate DVC measurements. On this basis, DVC strain mapping around breaks is further applied to two CFRPs with differing interfacial shear strength levels (by ∼17%). DVC results indicated that the strain recovery lengths were insensitive to this change in interfacial strength, which was rationalised by the absence of detectable debonds. Overall, this study provides novel insights into load redistribution under varying interfacial strengths, offering an experimental basis for advancing longitudinal tensile strength models. • DVC with 650 nm SRCT characterises load redistribution around single fibre breaks • SiO 2 particles produce well-dispersed speckle patterns with useful DVC fidelity • DVC estimates a 31 μm strain recovery length on either side of a single fibre break • Strain recovery lengths were insensitive to interfacial shear strength changes • Physical plausibility of DVC is confirmed by shear-lag and FE model comparisons

Multifunctional PLA/E-GMA/CB conductive polymer composites exhibiting enhanced toughness, electrically triggered shape memory, and EMI shielding

End-of-life degradation analysis of sustainable fiber-reinforced polymer composites under compost environment

Hybrid epoxy polymer composites with bamboo fiber and crab shell particulates: mechanical and tribological behaviour

Comprehensive investigation on mechanical properties of mango seed shell short fiber-reinforced epoxy based polymer composites

Recent research progress on the dispersion methodologies and their application within carbon nanotube-based polymer composites

Urban road dust represents a complex reservoir of microplastics (MPs) and anthropogenic magnetic particles, reflecting diverse emission sources and environmental processes. This study investigates the distribution, magnetic properties, and polymer composition of MPs in road dust collected from seven urban sites in Vienna, focusing on particle size fractions (0.2-0.1mm, 0.1-0.05mm, and <0.05mm) and magnetic separation. Magnetic susceptibility (χ), frequency-dependent susceptibility (χfd%), anhysteretic remanent magnetization (χARM), and hysteresis parameters were measured to characterize magnetic minerals, while MPs were quantified and identified by polymer type. The finest fraction was strongly magnetic, enriched in superparamagnetic and ferrimagnetic particles, whereas the intermediate and coarse fractions contained both magnetic and nonmagnetic components. The magnetic fraction contained up to seven times more MPs than the nonmagnetic fraction, with the highest concentration of 3500 particles g-1. Dominant MPs were polyurethane, polyvinyl chloride, and polyethylene, while <0.05mm exhibited 100% magnetic share, leaving no nonmagnetic material for identification. Sankey diagrams revealed clear flows of polymers across particle sizes and magnetic subfractions. The MP pollution load index showed that magnetic fractions dominate overall contamination, particularly in coarser particles, whereas nonmagnetic fractions contribute primarily to intermediate sizes. Hierarchical cluster analysis highlighted co-varying patterns among MPs, magnetic parameters, and traffic intensity, suggesting that local environmental factors influence MP distribution beyond direct traffic load. These findings underscore the utility of combined granulometric and magnetic fractionation for tracing MPs in urban dust, providing insights into the sources, distribution, and potential risks of MP pollution in urban ecosystems.

Hybrid Monte Carlo–MLP prediction of tunneling percolation and conductivity in conductive polymer composites under compressive strain

Microplastic pollution presents major environmental and health challenges, requiring accurate identification and quantification to assess its distribution and impact. Conventional methods such as chromatography and spectrometry provide precise results but are destructive, time-consuming, and resource intensive. Hyperspectral Imaging in the Near-Infrared range (HSI-NIR) offers a non-destructive alternative by capturing both spectral and spatial information, though analysis of its large, noisy datasets remains difficult. This study introduces an analytical pipeline combining HSI-NIR with optimized preprocessing and a machine-learning-based Multi-Layer Perceptron (MLP) model for pixel-wise classification of microplastic particles. The shallow MLP architecture effectively handles high-dimensional data using predefined spectral features. The approach was applied to samples from Lanzarote Island, the Wadden Sea, and the Waal and Rhine rivers, accurately identifying polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and polystyrene (PS). The MLP model outperformed Support Vector Machines, Random Forests, and Partial Least Squares Discriminant Analysis in polymer identification. PE and PP were dominant across all sites, with PET and PS in lower proportions. River samples showed higher microplastic concentrations in the Rhine than in the Waal, with polymer composition stable across depths. Code available at: https://github.com/petroshatt/hyperplastics.

Mechanical and thermal properties analysis of a hedgehog spine-inspired hollow woven shape memory polymer composite

Effects of random microvoid defects on the strength of carbon fiber-reinforced polymer composites

To compare the wear, fracture strength, and reliability of definitive resin three-unit fixed dental prostheses (FDPs) additively manufactured (AM) with different technologies to those subtractively manufactured (SM) from a high-impact polymer composite (HIPC). Thirty-two three-unit posterior FDPs (1-mm chamfer finish line, connector cross-sectional area: 16 mm2, minimum occlusal thickness: 1 mm, cement space: 100 µm) were either AM from a resin for definitive use (VarseoSmile Triniq) using digital light processing (AM-DLP), low force display (AM-LFD), or liquid crystal display (AM-LCD) technologies, or SM from a HIPC (SM-HIPC) (n = 8). All FDPs replaced the right second premolar. All FDPs were scanned before and after thermomechanical aging and subjected to load-to-fracture testing. Pre- and post-aging scans were digitally assessed for maximum wear depth and volume loss. Wear and fracture data were analyzed using one-way analysis of variance and Tukey tests, while chi-squared tests were used to evaluate Weibull parameters (α = 0.05). Mean fracture loads ranged from 1013 to 2725 N, while mean characteristic strength values ranged from 1072 to 2895 N. SM-HIPC mostly had lower wear (P ≤ 0.018), and AM-DLP had lower volume loss than AM-LFD and AM-LCD (P < 0.001). SM-HIPC showed the highest fracture load and characteristic strength, while AM-LFD had higher fracture load and characteristic strength than AM-LCD (P ≤ 0.001). SM-HIPC demonstrated better wear resistance along with the highest fracture and characteristic strength. Among AM FDPs, AM-DLP showed the lowest volume loss, while AM-LFD withstood higher loads and exhibited greater characteristic strength than AM-LCD. Three-unit FDPs fabricated with tested AM resin and digital light processing or low force display technologies may be suitable alternatives to those in high-impact polymer composite considering the reported masticatory forces of the molar region (1110 N). Nevertheless, they might also be more prone to complications related to wear.

Impacts of conductive phase concentration on flaw sensing properties of coil-shaped conductive polymer composite