Search

We introduce a method utilizing single laser-generated cavitation bubbles to stimulate cellular mechanotransduction in dermal fibroblasts embedded within 3D hydrogels. We demonstrate that fibroblasts embedded in either amorphous or fibrillar hydrogels engage in Ca2+ signaling following exposure to an impulsive mechanical stimulus provided by a single 250 µm diameter laser-generated cavitation bubble. We find that the spatial extent of the cellular signaling is larger for cells embedded within a fibrous collagen hydrogel as compared to those embedded within an amorphous polyvinyl alcohol polymer (SLO-PVA) hydrogel. Additionally, for fibroblasts embedded in collagen, we find an increased range of cellular mechanosensitivity for cells that are polarized relative to the radial axis as compared to the circumferential axis. By contrast, fibroblasts embedded within SLO-PVA did not display orientation-dependent mechanosensitivity. Fibroblasts embedded in hydrogels and cultured in calcium-free media did not show cavitation-induced mechanotransduction; implicating calcium signaling based on transmembrane Ca2+ transport. This study demonstrates the utility of single laser-generated cavitation bubbles to provide local non-invasive impulsive mechanical stimuli within 3D hydrogel tissue models with concurrent imaging using optical microscopy. STATEMENT OF SIGNIFICANCE: Currently, there are limited methods for the non-invasive real-time assessment of cellular sensitivity to mechanical stimuli within 3D tissue scaffolds. We describe an original approach that utilizes a pulsed laser microbeam within a standard laser scanning microscope system to generate single cavitation bubbles to provide impulsive mechanostimulation to cells within 3D fibrillar and amorphous hydrogels. Using this technique, we measure the cellular mechanosensitivity of primary human dermal fibroblasts embedded in amorphous and fibrillar hydrogels, thereby providing a useful method to examine cellular mechanotransduction in 3D biomaterials. Moreover, the implementation of our method within a standard optical microscope makes it suitable for broad adoption by cellular mechanotransduction researchers and opens the possibility of high-throughput evaluation of biomaterials with respect to cellular mechanosignaling.

Tensile testing probably represents the foremost important mechanical test that can performed on materials. This characterization has great relevance on polymeric materials, where the evaluation of the polymer goes beyond the pure chemical composition analysis. On the other hand, chemical labs are not always equipped with complete tensile machines due to space and budget constraints while often rely on much simpler machines usually provided with a dynamometer only. In this contest, the goal of the work is to provide a useful and effective method to estimate the stress–strain curve based only on force (and therefore the specimen stress) data. Of course, to recover the missing information (i.e. the sample elongation, and thus its strain) a suitable model of the tensile machine is needed to complement the dynamometer measures. Throughout the paper the steps to achieve such a model are described, together with an extensive experimental validation: firstly, we validated the method on metals which exhibit a well-defined behaviour. Then, we selected three different polymeric materials (polyvinyl alcohol, polydimethylsiloxane and natural rubber) in order to assess the performances of proposed approach in estimating their stress–strain characteristics. The obtained results confirmed the suitability and effectiveness of the proposed method in real-world applications. [ABSTRACT FROM AUTHOR]

Currently, flexible electronic devices based on ionic conductive hydrogels are receiving widespread attention in the field of human health detection. In this paper, a facile one‐pot method is proposed for the preparation of ionic organic hydrogels, in which polyvinyl alcohol (PVA), cellulose nanofiber (CNF), and graphene oxide (GO) are dissolved in dimethyl sulfoxide‐water (DMSO/H2O), and the organic hydrogel is obtained by a freezing–thawing process. The ionic organic hydrogel with excellent properties is then prepared by soaking the hydrogel in a calcium chloride (CaCl2) solution using a salting‐out strategy. The ionic organic hydrogel possesses good tensile (283%) and strength (0.3 MPa), super electrical conductivity (7.72 S/m), and high strain sensitivity [gauge factor (GF) up to 5.22]. Meanwhile, it has excellent anti‐freezing and moisturizing properties. In addition, the ionic organic hydrogels can be used in flexible strain sensors and triboelectric nanogenerators to realize real‐time monitoring of human motion, traceless writing, and energy conversion. It is foreseen that the prepared ionic organic hydrogels provide a feasible method for realizing the long‐term use of wearable electronic devices in extreme environments and daily life. [ABSTRACT FROM AUTHOR]

Autonomic self‐healing films have shown limited mechanical strength, hindering their application as biomaterials, particularly in skin bioengineering. To address this challenge, we developed polyvinyl alcohol (PVA)‐tannic acid (TA)‐based membranes with improved self‐healing properties and strong mechanical performance. Using a blade coating method and freeze–thaw cycles (−10°C for 1 h, followed by room temperature thawing), the synthesized membranes demonstrated a tensile strength of 8.8 MPa before healing and 7.6 MPa after healing, achieving an 88% healing efficiency. Membrane thickness showed a slight reduction from 465 to 432 μm posthealing. After 3000 bending cycles at a 1 cm radius, the membranes maintained flexibility with no significant changes in water vapor transmission rate (WVTR) (7.66 g/m2·day) or oxygen transmission rate (OTR) (0.13 cm3/m2·day·bar). These results underscore the membranes' suitability for dynamic skin environments, combining robust mechanical properties with excellent self‐healing capabilities. The PVA‐TA membranes present a promising solution for advanced skin bioengineering applications. [ABSTRACT FROM AUTHOR]

This study evaluates the structural performance of Polyvinyl Alcohol Cementitious Composites (PVCC)-layered reinforced concrete beams with coal ash under static loading. Experimental investigations included first crack load, ultimate load, load-deflection behavior, ductility, stiffness, and energy absorption. Results highlight the influence of Polyvinyl Alcohol-(PVA) fiber dosage on structural behavior. The control specimen exhibited an initial crack load of 80kN, with subsequent specimens showing varied crack initiation loads influenced by PVA fiber content. Optimal performance was observed at 1.2% PVA fiber dosage, with higher dosages leading to earlier crack initiation. Ultimate load carrying capacity increased with PVA fiber addition, reaching a peak at 1.2% dosage before slight decreases occurred with higher dosages. Load-deflection behavior demonstrated the superior performance of PVCC layered beams, particularly specimen BP3, attributed to optimal fiber content. Ductility, stiffness, and energy absorption increased with PVA fiber reinforcement, with 1.2% dosage yielding optimal results. Excessive fiber content led to diminishing returns. Energy index analysis revealed superior energy dissipation in specimens with higher PVA fiber content, emphasizing the effectiveness of fiber reinforcement in enhancing structural performance. Overall, the study underscores the importance of optimizing PVA fiber dosage to maximize structural resilience and load-bearing capacity in PVCC-layered concrete beams with coal ash. [ABSTRACT FROM AUTHOR]

Purpose: Compare the safety and efficacy of polyvinyl alcohol particles (PVA) versus trisacryl gelatin microspheres (Embospheres) versus hydrogel microspheres coated with polyzene-F (Embozenes) for prostatic artery embolization (PAE) to treat patients with benign prostatic hyperplasia (BPH). Materials and methods: A single-center prospective cohort study from 2019 to 2023, including patients with international prostate symptom score (IPSS) ≥ 15 and/or quality of life score (QoL) ≥ 4. Allocation to embolic agents was performed chronologically: 100–300 µm PVA (n = 53), followed by 300–500 µm Embospheres (n = 50), and finally, 400 µm Embozenes (n = 50). All patients were evaluated at baseline and at 1 and 6 months after PAE with IPSS/QoL; peak urinary flow rate, post-void residual volume, and prostate volume with ultrasound and prostate-specific antigen. Adverse events and the need for prostatic re-interventions were assessed. Results: There were no significant baseline differences between the three groups except for patient age (62.5 years PVA; 66.1 years Embospheres and 66.6 years Embozenes; p = 0.019). There were no major adverse events and no differences between groups regarding minor adverse events. All outcome measures improved significantly from baseline, with no significant differences between groups. Mean ± standard deviation IPSS/QoL improvement at 6 months: −10.7 ± 7.9/−2.2 ± 1.7 PVA; −10.4 ± 7.3/−2.0 ± 1.5 Embospheres; −10.4 ± 7.0/−2.2 ± 1.6 Embozenes (p = 0.987). Re-intervention rates after 6 months: 9% (n = 5/53) PVA; 14% (n = 7/50) Embospheres; 8% (n = 4/50) Embozenes (p = 0.591). Conclusions: PAE with PVA particles, Embospheres, and Embozenes is equally safe and effective in treating BPH-related lower urinary tract symptoms. Clinical relevance statement: This is the first prospective study showing equivalence between the most frequently used embolic agents for prostatic artery embolization. Key Points: Different particles can be used interchangeably for prostatic artery embolization. The improvements in measured metrics were the same between groups, with no differences in adverse events. The need for prostatic medication and re-intervention rates were the same at 1 and 6 months after embolization. [ABSTRACT FROM AUTHOR]

This study investigates the dielectric behavior of polyvinyl alcohol (PVA) composites incorporating FeGaInS4 layered crystals as fillers at varying weight concentrations (1 wt.%, 3 wt.%, 5 wt.%, and 8 wt.%), synthesized using the solution mixing method. The layered structure of FeGaInS₄ facilitates distinctive interfacial interactions with the polymer matrix, potentially augmenting dielectric properties. Structural characterization was performed using X-ray diffractometry and Fourier-transform infrared (FTIR) spectroscopy, while dielectric properties were assessed via dielectric spectroscopy across different filler concentrations, temperatures, and frequencies of applied alternating current. FTIR analysis elucidated polymer-filler interactions, and dielectric spectroscopy results demonstrated an increase in dielectric permittivity with temperature and a decrease with frequency. Notably, the composite with 1 wt.% filler exhibited the highest dielectric permittivity, attributed to the uniform dispersion of FeGaInS₄ crystals within the matrix, enhancing interfacial polarization. The tangent loss angle was observed to rise with temperature, corresponding to increased electrical conductivity. The Correlated Barrier Hopping (CBH) model was applied to evaluate system parameters (s, WM, Rω, and N) for PVA and FeGaInS₄-based composites at 293 K and 313 K under a frequency of 2 × 103 Hz, indicating charge transport via electron hopping between localized states mediated by zone and hopping conductivity mechanisms. Activation energy values were determined for composites with varying filler concentrations, ranging from 0.71–0.30 eV for pure PVA to 1.46–0.85 eV (1 wt.%), 0.57–0.27 eV (3 wt.%), 0.71–0.30 eV (5 wt.%), and 0.70–0.34 eV (8 wt.%). The findings reveal that increasing the semiconductor filler content enhances electrical conductivity, underscoring the potential for optimizing the dielectric and electrical properties of PVA composites through controlled filler concentration. [ABSTRACT FROM AUTHOR]

A novel film was developed from barberry (BA) anthocyanins immobilized on cobalt-based metal–organic framework (Co-MOF) nanoparticles utilizing biodegradable polyvinyl alcohol (PVA) and chitosan nanofiber (ChNF) as intelligent and active packaging for red meat freshness. The aim of the study was evaluated in two scenarios, the first evaluation of the potential of Co-MOF for embedding in packaging films as antimicrobial properties and cobalt color change due to amine release and pH change, and the second evaluation of the application of Co-MOF in the controlled release of BA anthocyanins as antioxidant properties and color changes of food packaging films during spoilage of red meat. The findings showed that the addition of Co-MOF nanoparticles significantly increased the PVA/ChNF film's specific surface area, and Co-MOF's better capacity to concentrate volatile amines allowed the film to detect freshness extremely sensitively, and the antibacterial capabilities of the films for E. coli, S. aureus, and P. fluorescence bacteria were 20.3 ± 0.3 mm, 21.6 ± 0.2 mm, and 19.6 ± 0.4 mm, respectively. Moreover, the inclusion of BA and Co-MOF significantly improves the tensile strength (from 67.2 to 81.3 MPa), flexibility (18.9 to 22.3%), UV protection, water vapor resistance, and sensitivity to ammonia-induced discoloration of the PVA/ChNF film. PVA/ChNF/Co-MOF and PVA/ChNF/Co-MOF/BA films' colors changed from pink to dark brown and from deep peach to black-greenish-brown when used to track the spoilage of red meat. In conclusion, it was possible to use the created films as intelligent and active food packaging materials. [ABSTRACT FROM AUTHOR]

In order to improve the application performance of polyvinyl alcohol and starch as sizing agents on the surface of paper, Paper surface sizing agents (CPSn-PVA) with different degrees of crosslinking were prepared by using y-glycidyl etheroxypropyltrimethoxyprop-ylsilane (KH560) and borax (STB) as crosslinking agents, and crosslinking modified starch (PS) and polyvinyl alcohol (PVA1799). The properties of the paper surface sizing agent were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy and stability testing, and the effects of the addition ratio of KH560 and borax on the performance of the paper surface sizing agent and the physical properties of the paper after sizing were discussed. The experimental results show that when the addition amount of borax is 0.1 g and the addition amount of KH560 is 3 g, the tensile strength of the adhesive film can reach 25.6 MPa, and the elongation at break is 326%. At the same time, the multi crosslinked PVA1799 paper surface sizing agent showed good application performance. Compared with the original paper, the paper's folding enderance, tearing index and contact angle increased by 6700%,65.04%, and 89.7% respectively after sizing. [ABSTRACT FROM AUTHOR]

Despite being the key component in modern electronic devices or power systems, ceramic dielectric capacitors have drawbacks like low energy storage density and efficiency that limit their extensively wide application. This work adopted a different route to improve energy storage performance compared with the frequently utilized composition modification. 0.98Ba0.65Sr0.245Bi0.07TiO3‐0.02Ce Pb‐free ceramics with different polyvinyl alcohol (PVA) contents were prepared through viscous polymer processing. The rheological and energy‐storing performance were systematically studied. It can be seen that high PVA content results in more pores and larger grain sizes that will deteriorate the breakdown strength of ceramics. The highest breakdown strength reached 420 kV/cm while the concentration of PVA was 5 wt%. The mechanism of grain sizes on breakdown strength is studied by electrical tree simulation based on COMSOL. Viscous polymer processing with proper PVA content is very effective in generating dense and homogenous structures. Finally, the ceramic with 5 wt% PVA possesses a high density of up to 4.41 J/cm3 and an efficiency of about 84.21% at 420 kV/cm. Simultaneously, this ceramic improved stability of both temperature (30–150°C) and frequency (1–300 Hz) at 350 kV/cm, while the η kept above 90% and Wrec exceeding 3.6 J/cm3. [ABSTRACT FROM AUTHOR]

This paper aims to develop a novel method of preparing self-sensing concrete with recycled coarse aggregate (RCA) impregnated by polyvinyl alcohol (PVA) solution containing nano carbon black (Nano CB). The four-electrode method was adopted to investigate the influence of modified RCA substitution ratio, temperature and water content on the electrical resistivity of as-fabricated modified RCA concrete. In addition, the effects of modified RCA substitution ratio and loading rate on the piezoresistivity were explored. The results indicate that the modification have successfully attached Nano CB to the surface of RCA, and the micro-pores on the RCA surface have been filled with PVA/ Nano CB slurry, meanwhile, the water absorption decreased by 28.8%, and the crushing value decreased by 42.3%. The workability and compressive strength of concrete are improved by the modification of RCA as well. As the RCA substitution ratio increases, the resistivity of concrete first decreases slowly, then sharply and finally stabilizes. The percolation threshold of modified RCA concrete is approximately 60% substitution ratio of modified RCA (1.76 wt.% Nano CB by weight of cement). Moreover, the conductivity of modified RCA concrete possesses positive temperature sensitivity and humidity adaptability. Under cyclic loading of stress, the order of the maximum FCR value and the stress sensitivity of modified RCA concrete is: percolation zone > conductive zone > insulation zone. The specimens with modified RCA substitution ratio of 60% (in percolation zone) exhibit the best piezoresistive response compared to specimens with substitution ratios of 40% (in insulation zone) and 80% (in conductive zone). In addition, regardless of the modified RCA substitution ratio, the stress sensitivity of specimens decreases with the increase of loading rate. [ABSTRACT FROM AUTHOR]

Creating durable, motion-compliant neural interfaces is crucial for accessing dynamic tissues under in vivo conditions and linking neural activity with behaviors. Utilizing the self-alignment of nano-fillers in a polymeric matrix under repetitive tension, here, we introduce conductive carbon nanotubes with high aspect ratios into semi-crystalline polyvinyl alcohol hydrogels, and create electrically anisotropic percolation pathways through cyclic stretching. The resulting anisotropic hydrogel fibers (diameter of 187 ± 13 µm) exhibit fatigue resistance (up to 20,000 cycles at 20% strain) with a stretchability of 64.5 ± 7.9% and low electrochemical impedance (33.20 ± 9.27 kΩ @ 1 kHz in 1 cm length). We observe the reconstructed nanofillers' axial alignment and a corresponding anisotropic impedance decrease along the direction of cyclic stretching. We fabricate fiber-shaped hydrogels into bioelectronic devices and implant them into wild-type and transgenic Thy1::ChR2-EYFP mice to record electromyographic signals from muscles in anesthetized and freely moving conditions. These hydrogel fibers effectively enable the simultaneous recording of electrical signals from ventral spinal cord neurons and the tibialis anterior muscles during optogenetic stimulation. Importantly, the devices maintain functionality in intraspinal electrophysiology recordings over eight months after implantation, demonstrating their durability and potential for long-term monitoring in neurophysiological studies. Creating durable, motion-compliant neural interfaces is essential for accessing dynamic tissues in vivo and linking neural activity with behaviors. Here, the authors introduce carbon nanotube-enhanced polyvinyl alcohol hydrogels, creating electrically anisotropic, fatigue-resistant fibers for long-term intraspinal electrophysiological recordings in mice. [ABSTRACT FROM AUTHOR]

To push upper boundaries of thermal conductivity in polymer composites, understanding of thermal transport mechanisms is crucial. Despite extensive simulations, systematic experimental investigation on thermal transport in polymer composites is limited. To better understand thermal transport processes, we design polymer composites with perfect fillers (graphite) and defective fillers (graphite oxide), using polyvinyl alcohol (PVA) as a matrix model. Measured thermal conductivities of ~1.38 ± 0.22 W m-1 K-1 in PVA/defective filler composites is higher than those of ~0.86 ± 0.21 W m-1 K-1 in PVA/perfect filler composites, while measured thermal conductivities in defective fillers are lower than those of perfect fillers. We identify how thermal transport occurs across heterogeneous interfaces. Thermal transport measurements, neutron scattering, quantum mechanical modeling, and molecular dynamics simulations reveal that vibrational coupling between PVA and defective fillers at PVA/filler interfaces enhances thermal conductivity, suggesting that defects in polymer composites improve thermal transport by promoting this vibrational coupling. [ABSTRACT FROM AUTHOR]

This study examines the thermal, structural, optical, and morphological properties of calcium carbonate (CaCO 3) fibers produced by a novel method of calcination of electrospun polyvinyl alcohol (PVA) fibers reinforced with calcium acetate monohydrate (CaAc). TGA and DSC show improved enhanced thermal stability of PVA-CaAc fibers compared to pure PVA. Structural analysis by DRX confirms the formation of calcite as the primary crystalline phase. SEM images show a significant reduction in the diameter of the calcined fibers and the development of a porous morphology. Reflection-transmission spectrophotometry shows a band gap of 3.45 eV for the CaCO 3 fibers with possible contributions from carbon traces, which may further reduce the bandgap and, therefore, prove to be suitable photocatalysts for visible-light-driven applications. For this reason, the photocatalytic activity of the calcined fibers was analyzed under UV and solar irradiation for the photodegradation of methylene blue in aqueous solutions. These results highlight the improved thermal and structural properties of the CaCO 3 fibers, which make them promising candidates for advanced material applications, especially in the biomedical and environmental fields. [ABSTRACT FROM AUTHOR]

Conductive hydrogels have shown substantial potential in the field of medication monitoring due to their exceptional flexibility and biocompatibility. However, some challenges such as low ionic conductivity, restricted mechanical properties, and limited sensitivity have hindered their further development. Inspired by fiber-like aligned tendon tissues, robust and conductive hydrogels with multi-hierarchical structures via constructing cellulose-reinforced polyvinyl alcohol (PVA) networks using a directional freeze-casting technique combined with Zn2+/Li+ bimetallic ion coordination were developed. As a result, high mechanical properties (σ = 1.5 MPa, ε = 1020%), a high conductivity of 3.5 S m−1 and a low strain detection limit of 0.5% of the hydrogels were simultaneously achieved, ascribed to the multi-hierarchical structure interactions such as polymer chain orientation, formation of nanocrystalline domains, and ionic coordination effects. Interestingly, the conductive hydrogel showed great potential as an electrolyte of flexible zinc-ion batteries. More importantly, for the first time, a strong correlation between varying wind forces and the relative resistance of the hydrogel was created and therefore an intelligent real-time medication monitoring system was then well designed utilizing the ionic hydrogels as a flexible sensor, which can be used to monitor the drug-intake for infant or elder asthmatic patients. This work provides a green and biomimetic strategy to construct ionic conductive hydrogels for medical monitoring. [ABSTRACT FROM AUTHOR]

The construction of heat transfer channels based on highly thermally conductive fillers in a polymer matrix is important for improving the thermal conductivity of thermal management materials (TMMs). However, owing to the inhomogeneity of filler distribution and the limitation of the mechanical properties of polymers, it is a great challenge to achieve both high thermal conductivity and excellent mechanical properties. In this work, a simple air/water interfacial (AWI) assembly was implemented for the preparation of boron nitride–silver nanowires/polyvinyl alcohol (BN–Ag NWs/PVA) films. BN–Ag NW hybrid fillers were obtained through the ultrasonic treatment of amino-functionalized BN flakes with an Ag NW solution, followed by drying. BN–Ag NWs/PVA composite films were prepared via AWI assembly on the surface of a saturated sodium sulphate solution based on the salting-out effect. BN flakes tended to be oriented and aligned along the in-plane direction, and Ag NWs could bridge different BN flakes to form thermal conductivity pathways. The in-plane thermal conductivity of the BN–Ag NWs/PVA film was 1.24 W m−1 K−1 at a filler content of 25 wt%, which was about 4.8 times higher than that of a pure PVA film. Meanwhile, the tensile strength of the BN–Ag NWs/PVA film could reach 54.3 MPa owing to the regular distribution of hybrid fillers. The simultaneous improvement of thermal conductivity and mechanical properties was beneficial for the practical application of BN–Ag NWs/PVA films. [ABSTRACT FROM AUTHOR]

Carbon fibers from polyvinyl alcohol (PVA) was achieved by the electrospinning technique, which was subsequently followed by the stabilization and carbonization of electrospun PVA fibers. The XRD pattern of PVA fiber confirms the change in the structure of PVA nanofibers and carbonized PVA from temperatures of 200, 300, 400, 500, and 700 °C, resulting in a structural evolution from fibrous to plate-like and dot carbon compounds. The SEM image of the PVA precursor reveals the presence of fibers exhibiting a smooth surface following the stabilization and carbonization processes at temperatures below 500 °C. Furthermore, the image depicts fibers that melt and transform into a carbon layer at a higher carbonization temperature ranging from 600 to 700 °C. TEM results show the formation of carbon sheets and dots, with an average diameter of 8.2 nm. The evolution that occurs from fibers to carbon sheet due to the melting process indicates a change in the morphology of 1D to graphenic carbon. The identification of carbon–oxygen functional groups, such as C = C (carbon with sp2 hybridization), C–C (carbon with sp3 hybridization), and C = O bonds, has been successfully detected and analysed using both XPS and Raman spectroscopy techniques. The results of the XPS profile fitting, as proven by Raman spectra, produce a graphenic carbon containing a 2D structure, with the total sp2 fraction increasing in the increasing carbonization temperature. This is also followed by significantly increasing electrical conductivity. So, the carbonized PVA nanofiber has the potential to be applied in electronic and energy storage device applications. This is also followed by an increase in electrical conductivity due to the formation of more carbon functional groups compared to less oxygen. Thus, carbonized PVA nanofibers have great potential for application in electronic devices and energy storage applications such as batteries and supercapacitors. [ABSTRACT FROM AUTHOR]

Introduction: The image formation process of conventional pulse-echo Ultrasound mainly uses the backscattered amplitude and assumes constant attenuation and speed of sound in the penetrated media. Thus, many commercially available ultrasound imaging phantoms use only a limited choice of materials with simple geometric shapes. Part of today's research in ultrasound is to gain more information on the acoustic properties of the object imaged. These advanced imaging and reconstruction procedures require more complicated phantom designs that contain different materials with precisely designable acoustic properties for validation and quality assurance (QA). Methods: To fabricate such phantoms, we produced molds for casting ultrasound phantoms using additive manufacturing. Phantom materials used were based on agar and polyvinyl alcohol. To adapt the speed of sound glycerol was added to the mixtures. As glycerol diffuses out of the phantom material, polluting the surrounding water, we designed a watertight sample holder. The effect of the freeze-thaw cycles (FTCs) on the acoustic properties of the polyvinyl alcohol (PVA)-based phantoms was also investigated. Speed of sound and attenuation were determined for both phantoms materials, and Shore hardness measured for the PVA-based phantoms. Results: Shore hardness of the PVA phantoms increased by up to 79% of the initial value with increasing number of freeze-thaw cycles, but showed a saturation after 5 FTCs. However, the number of FTCs had only a small effect on the speed of sound and attenuation, as the sound speed increased slightly from 1,530.14 m/s to 1,558.53 m/s, (1.86%) and the attenuation exhibited only an increase of 6.75%. In contrast, differences of around 100 m/s in the speed of sound in the PVA phantoms (from 1,558.53 to 1,662.27 m/s), as well as in the agar-based phantoms (from 1,501.74 to 1,609.36 m/s) could be achieved by adding glycerol, making these materials appropriate candidates for the design and fabrication of US phantoms with defined sections and details with different speed of sound and attenuation. The use of the sample holder showed only an influence of 0.63% on the measured speed of sound. Discussion: 3D printed molds led to an improved manufacturing process as well as a free choice of the shape of the phantoms. A sample holder could prevent contamination of the water with no significant differences in the measured speed of sound. [ABSTRACT FROM AUTHOR]

Based on the requirements of resin‐based plugging agents on initial viscosity, gel time and cost, the urea‐formaldehyde resin Poly‐UF was synthesized via aqueous solution polymerization. Subsequently, the Poly‐UF was further modified by using melamine, polyvinyl alcohol (PVA), and oxidized starch to enhance its application performances, which were marked by Poly‐UF‐M, Poly‐UF‐PVA and Poly‐UF‐OS, respectively. Simultaneously, the relationship between the preparation process, structural, and performance characteristics of the different resin types was investigated using a single‐factor experimental approach, specifically, the solid content, viscosity, and free formaldehyde content were evaluated to gauge its application performance. In this study, the chemical structure, thermal stability and microscopic morphology of Poly‐UF‐M, Poly‐UF‐PVA and Poly‐UF‐OS were studied by using FTIR, TG‐DTG and SEM. As a result, it was confirmed that the Poly‐UF was successfully modified, and the thermal stability was obviously improved, and the microstructure was further enhanced by melamine, PVA and oxidized starch. The outcomes revealed a notable reduction in free formaldehyde content and a significant increase in solid content for Poly‐UF‐M, Poly‐UF‐PVA, and Poly‐UF‐OS, specifically, the free formaldehyde content decreased by 47.15%, 36.59%, and 32.52%, respectively, while the solid content increased by 3.47%, 1.62%, and 1.39%, respectively. Moreover, the acid and alkali solubility, mechanical strength of cured Poly‐UF‐M, Poly‐UF‐PVA and Poly‐UF‐OS were improved attribute to excellent membrane‐forming performance. The innovation of this study is that the systematic investigation and optimization of urea‐formaldehyde resin are presented, providing technical insights on its utilization as a plugging agent in fractured and caved oil and gas reservoirs. [ABSTRACT FROM AUTHOR]

Almond shells (ASs) are a potential source of cellulose that could be obtained through sustainable methods for their valorisation. Biocomposites (BCs) from polyvinyl alcohol (PVA) and cellulose are interesting materials for developing sustainable packaging materials. BC based on PVA and AS cellulose were obtained by melt blending and compression moulding, by using subcritical water extraction at 160 or 180 °C, and subsequent bleaching with sodium chlorite (C) or hydrogen peroxide (P) to purify cellulose. The influence of the purification method on the properties of BC was analysed. Fibres treated with C were better dispersed in composites than those bleached with P. Residual phenolic compounds in the fibres provide the composite with ABTS∙+ scavenging capacity in line with the residual lignin content of the fibres. Both the presence of phenols and dispersed fibres reduced the film transparency, mainly in the UV range. Fibres enhanced the oxygen barrier capacity of composites, and those treated with HP also improved the water vapour barrier capacity. Fibres treated with C better promoted the increase in the elastic modulus of the composites, due to their highest crystallinity and dispersibility, while favoured the PVA crystallisation. Therefore, the obtained AS cellulose fibres could be used to obtain thermoprocessed PVA biocomposites for food packaging applications. [ABSTRACT FROM AUTHOR]

An original design of a simple bioreactor was used to fabricate two tubular, 200 cm long BC structures by culturing Komagataeibacter sucrofermentans B-11267 on a molasses medium. In addition, a tubular BC-based biocomposite with improved mechanical properties was obtained by combining cultivation on the molasses medium with in situ chemical modification by polyvinyl alcohol (PVA). Moreover, the present study investigated the BC production by the K. sucrofermentans B-11267 strain on the media with different molasses concentrations under agitated culture conditions. The dynamics of sugar consumption during the cultivation were studied by HPLC. The structure and physicochemical properties of BC and tubular BC structures were characterized by FTIR spectroscopy and X-ray diffraction (XRD). Thus, the findings indicate that K. sucrofermentans B-11267, when cultivated in a molasses medium, which is such a cheap waste product in the sugar industry, forms a significant amount of BC with a high crystallinity degree. The BC tubular structures demonstrated great potential for their application in biomedicine as artificial blood vessels and conduits for nerve regeneration. [ABSTRACT FROM AUTHOR]

We report a comprehensive investigation of the photophysical properties of Hoechst 33258 (HOE) embedded in polyvinyl alcohol (PVA) films. HOE displays a bright, highly polarized, blue fluorescence emission centered at 430 nm, indicating effective immobilization within the polymer matrix of PVA. Its fluorescence quantum yield is notably high (~0.74), as determined relative to a quinine sulfate standard. In addition, we observed that HOE-doped PVA films exhibit room temperature phosphorescence (RTP) that remains visible for several seconds after UV excitation ceases. The slightly negative phosphorescence anisotropy implies that the triplet–singlet radiative transition is orthogonal to the singlet–singlet transition governing fluorescence. Notably, we observed that direct triplet-state excitation at longer wavelengths (beyond the primary absorption band) produces highly polarized RTP. We believe this possibility of direct triplet-state excitation opens new avenues for studying RTP in polymer-immobilized molecules. [ABSTRACT FROM AUTHOR]

Chitosan/polyvinyl alcohol nanofibrous mats loaded with nano-hydroxyapatite and/or curcumin are successfully fabricated by the electrospinning method for the first time. Nano-hydroxyapatite is prepared by the co-precipitation method. The XRD pattern of calcined powder at 700 °C for 2 h reveals the presence of hydroxyapatite as a sole phase. FT-IR confirms its purity. The morphology of the hydroxyapatite is studied by HR-TEM. Nano-hydroxyapatite and curcumin are added at 5 wt% with respect to the polymer weight. XRD, FE-SEM, FT-IR, and HR-TEM are used to characterize the fabricated nanofibrous mats. The results confirm the successful loading of nano-hydroxyapatite and curcumin within the fabricated mats. The in vitro antimicrobial results show that most of mats have significant antimicrobial effects against E. coli and S. aureus. The fabricated matd are biocompatible with fibroblasts and the presence of curcumin increases cell viability. Curcumin release from both CS/PVA/Cur and CS/PVA/HA/Cur nanofiber mats principally follows the Korsmeyer–Peppas and Peppas–Salhin models. [ABSTRACT FROM AUTHOR]

In this study, a mixed sol-gel technique using silicate, polyvinyl alcohol (PVA), and polyethyleneimine (PEI) was used to various polymers based on PEI and silica gel. The c-PEI blend co-polymer was synthesized by cross-linking branching PEI in an aqueous solution with PVA. The produced c-PEI particles were highly positively charged and fit inside the range of tens to hundreds of nanometers of silica gel. It has been shown that the prepared c-PEI nanocomposite is a very effective antimicrobial, anti-inflammatory, and antioxidant material. In addition to the appropriate investigation of the anti-inflammatory activity using human red blood cells (HRBCs) stabilization, the developed materials were used to explore antimicrobial activity against yeast (Candida albicans ATCC-10231), Gram-negative bacterial strain (Escherichia coli ATCC-25922), and Aspergillus niger NRRL-3 as a fungus. FTIR, XRD, TEM, TGA, and DSC were among the biological and chemical methods used to characterize the produced c-PEI nanocomposites. The agar diffusion method was used to assess the biological activity of the synthesized compounds, and the results revealed a range in their in vitro-antimicrobial inhibitory activity. Based on the type of pathogenic microbe, the majority of the test substances showed a wide range of activity. The examined substances may be appropriate for the creation of an innovative antibacterial and antifungal medicinal medication. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA)/polyvinylpyrrolidone (PVP)–blended nanofibers have garnered increasing interest in biomedical applications in tissue engineering. PVA-based biomaterials still have limitations that can restrict their use or performance, among which blending with PVP has shown promising results. The ultrafine nanofibers were obtained from PVA solutions, and different rough surface and fractal surface nanofibers resulted from adjusting the PVP concentration. In this study, the ultrathin PVA/PVP-blended nanofiber membranes were produced using electrospinning. The experimental results show the effects of varying the PVA/PVP ratio and solution concentration on nanofiber quality and diameter. It indicates that increasing the PVA/PVP ratio not only decreases the nanofiber diameter but also complicates the control over nanofiber quality, leading to uneven distribution and problematic film formation at higher PVP levels. The data obtained from the proposed models demonstrate high significance, as indicated by high F values and low p values, underscoring the role of PVP in nanofiber fabrication. Additionally, an artificial neural network (ANN) was developed, exhibiting strong predictive capability during the testing phase prior to the final fabrication stages. This study provides the importance of carefully adjusting the PVA/PVP ratio to maintain nanofiber uniformity and optimizing solution concentration to control fiber diameter effectively. [ABSTRACT FROM AUTHOR]

Sisal fibers treated with alkali and polyvinyl alcohol (PVA) through ultrasonic impregnation yield various modified fibers with enhanced properties. In this study, the influence of PVA adhesion on the tensile strength, water absorption and thermal stability of individual fiber and the change of interfacial shear strength with starch were investigated. The fiber was characterized by infrared spectroscopy and electron microscope. Results reveal that PVA not only coats the surface but also penetrates the fibers, significantly improving tensile strength. Weibull distribution analysis showed that the tensile strength of ASF increased by 42.99% and the interfacial shear strength increased by 140.5%. The tensile strength of the PSF-1.0, analyzed using Weibull distribution, increased by 50.1%, and the interfacial shear strength improved by 112.9%. The study confirms that alkali and PVA treatment is a cost-effective, biodegradable method to enhance the tensile and interfacial binding properties of natural fibers, making them suitable for reinforced starch-based composites. [ABSTRACT FROM AUTHOR]

Although bacterial cellulose-polyvinyl alcohol (BC-PVA) films exhibit a range of advantages such as enhanced elasticity, mechanical strength, and thermal stability, they still face several challenges, particularly in antibacterial performance. This drawback can hinder BC-PVA films to access to food packaging and preservation fields. The present study aimed to improve antibacterial performance of an active packaging film composed of BC-PVA films by incorporating nanoparticles (NPs) such as ZnO and Ag/ZnO biosynthesized using Eclipta prostrata (EP) plant extract. The results revealed the significant effect of ZnONPs and Ag/ZnONPs on the microstructure, water solubility, mechanical, water vapor permeability, oxygen permeability and antibacterial activity of BC-PVA composite films. The BC-PVA-Ag/ZnONP films possessed superior mechanical strength, reduced water vapor permeability and oxygen permeability compared to BC-PVA films. These composite films also displayed enhanced antimicrobial activity against both Gram-(+) and Gram-(−) bacteria. For packaging fresh strawberries, the BC-PVA-Ag/ZnONP films helped to extend shelf life, demonstrating their potential for various applications in active packaging field. [ABSTRACT FROM AUTHOR]

This study investigated the impact of glycerin plasticization, polyvinyl alcohol (PVA) and nano-montmorillonite (MMT) compounding, and organic acid cross-linking agent on the mechanical, microstructural, crystallinity, water absorption, and thermal characteristics of carboxymethyl cellulose (CMC)-based films. The developed manufacturing technique resulted in substantial improvements in the film's tensile strength and Young's modulus, which increased by 240% and 840%, respectively. However, there was a 27% reduction in elongation at break. Scanning electron microscopy revealed that the optimal MMT concentration, which prevented agglomeration within the polymer matrix, was 4 wt.%. Evaluations of hydrophilicity/hydrophobicity demonstrated a 24% reduction in moisture absorption and a 41% decrease in water vapor permeability for the CMC-based films. This reduction significantly lowered the solubility and swelling degree of the films by 63% and 93%, respectively. Notably, beyond a cross-linker concentration of 15 wt.%, this contribution diminished slightly. Thermal analysis indicated that glycerin reduced the film's glass transition temperature from 76.2 °C to 68.9 °C, while the addition of PVA and MMT increased this temperature by 22% and 53%, respectively. The optimal formulation for an effective food packaging film was identified as CMC/PVA/glycerin at a 1/1/2 ratio, with 4 wt.% MMT and 15 wt.% cross-linker. The resulting film demonstrated an improved shelf life for food products compared to polyethylene alternatives. [ABSTRACT FROM AUTHOR]

Integrating noble metal nanostructures, specifically silver nanoparticles, into sensor designs has proven to enhance sensor performance across key metrics, including response time, stability, and sensitivity. However, a critical gap remains in understanding the unique contributions of various synthesis parameters on these enhancements. This study addresses this gap by examining how factors such as temperature, growth time, and choice of capping agents influence nanostructure shape and size, optimizing sensor performance for diverse conditions. Using silver nitrate and sodium borohydride, silver seed particles were created, followed by controlled growth in a solution containing additional silver ions. The size and morphology of the resulting nanostructures were regulated to achieve optimal properties for biochemical sensing in wireless sensor networks. Results demonstrated that embedding these nanostructures in Polyvinyl Alcohol (PVA) matrices led to superior stability, maintaining 93% effectiveness over 30 days compared to 70% in Polyethylene Glycol (PEG). Performance metrics revealed significant improvements: reduced response times (1.2 ms vs. 1.5 ms at zero analyte concentration) and faster responses at higher analyte levels (0.2 ms). These outcomes confirm that higher synthesis temperatures and precise shape control contribute to larger, more stable nanostructures.The enhanced stability and responsiveness underscore the potential of noble metal nanostructures for scalable and durable sensor applications, offering a significant advancement over current methods. [ABSTRACT FROM AUTHOR]

Highly filled polymer fibers offer huge promise for radiation protection safety and wear comfort of personal protective equipment (PPE) in radiation environments. However, it usually sacrifices mechanical properties that directly related to practical usability. Here, as high as 75 wt% PbWO4 (PWO) particles have been filled in polyvinyl alcohol (PVA) fiber via tailoring their size and shape for enhanced γ‐rays shielding and good mechanical properties. Clearly shown that 0 dimensional (0‐D) PWO exhibits better dispersion and compatibility between the interfaces than 1‐D PWO in highly filled PVA fibers. In addition, 70 wt% 0‐D PWO/PVA fibers display better mechanical properties than 70 wt% 1‐D PWO/PVA fibers. Note that 75 wt% 0‐D PWO/PVA fibers show 1.02 cN/dtex of tensile strength. However, 75 wt% 1‐D PWO/PVA fibers fail to be fabricated smoothly. Importantly, the overlapped fabrics with 75 wt% 0‐D PWO/PVA fibers display 43.05% of γ‐ray shielding (105 keV) meanwhile it offers good air and water vapor permeability for wear comfort. The superior γ‐ray shielding ascribes the polymer fibers with the higher filling in comparison with its counterpart, which provides a practical means to design radiation protection safety and wear comfort of articles. Highlights: This work breaks the upper limit of filling in polymer fibersFiller structure can weigh the integrated properties of polymer fibers.0‐D PWO particles promote interfacial compatibility in highly filled fibers.Radiation protection safety and wear comfort of articles tend to be designed. [ABSTRACT FROM AUTHOR]

Achieving satisfactory separation of N, N‐Dimethylformamide (DMF)/water is still challenging in industrial wastewater treatment. To address this issue, a novel method involving pervaporation (PV) separation using polyvinyl alcohol/chitosan (PVA/CS) blend films is proposed. Various characterization methods confirmed the strong compatibility between PVA and CS, and the blending improved their mechanical properties and thermal stability. Heat treatment significantly reduced the swelling degree of the membranes. In a binary aqueous system with low concentrations of DMF, controlled separation can be achieved by adjusting the blending ratio of PVA to CS. The membranes exhibited preferential selectivity for DMF when the CS content is 40–75 wt%, which allowed for the concentration and recovery of DMF. At 20 °C with a feed of 10 wt% DMF solution, 2 h heat‐treated PVA/CS‐50 membrane exhibited the best performance, which could be attributed to its strong hydrogen bonding force, with a total flux of 484.09 g m−2 h−1 and a separation factor of 5.41 for DMF. The PVA/CS blend membranes exhibit excellent acid and alkali resistant and are promising candidates for the separation and recovery of DMF from industrial wastewater by membrane technology. [ABSTRACT FROM AUTHOR]

Cross‐linking of polyvinyl alcohol (PVA) and polyvinyl alcohol/Nafion (PVA/Nafion) electrospun nanofibers with sulfosuccinic acid (SSA) was investigated to assess their characterization and the effects of cross‐linking on the methanol permeability performance of the nanofibrous membranes. SSA was directly incorporated into the electrospinning polymer solution. The morphology, chemical functional groups, thermal stability, water stability and water swelling of the resulting nanofibers were examined. The effects of SSA concentration on ion exchange capacity (IEC) and methanol permeability of the nanofibrous membranes were discussed. Bead‐free and smooth nanofibers were produced for all SSA concentrations with a mean nanofiber diameter of 240–270 nm. It was shown that 15% SSA concentration was suitable for preserving the morphology of PVA nanofibers against water, while the morphology of PVA/Nafion nanofibers was preserved even without cross‐linking. The increase in SSA concentration led to increase in swelling in water. SSA cross‐linking was also shown to increase the thermal stability of the produced nanofibers. IEC increased by the increase in SSA concentration, while increase in SSA concentration led to a decrease in methanol permeability. [ABSTRACT FROM AUTHOR]

The composition of biogas consists mainly of CH4 (~60%) and CO2 (40%). To be considered a clean fuel, CH4 concentration in biogas must be increased to over 95%. In this study, membranes which were stacked in a chamber were utilized to purify biogas by passing biogas over them. These membranes were composed of polyethersulfone hollow fiber substrate coated with a "selective layer" made of cellulose nanocrystals (CNC‐0–2 wt) in polyvinyl alcohol (PVA) and l‐arginine as a CO2 carrier. Of the different CNC concentrations in PVA‐LA, CNC1/PVA‐LA (1.0 wt% CNC in PVA‐LA) displayed the lowest water contact angle of 17° (corresponding to higher moisture absorbing ability). With further increase in CNC concentration, even though CNC1.5/PVA‐LA showed the higher crystallinity (66%), and water contact angle increased (20°); reducing the chances of facilitated transport of CO2 through it. Biogas separation experiments were conducted at 90% RH and different feed pressures (0.8–1 bar) for various CNC concentrations. Increasing the CNC concentration led to a thicker selective layer, enhancing the CO2 permeability and selectivity up to CNC1/PVA‐LA. However, with the further addition of CNC, both permeability and selectivity decreased. At 90% RH and 1 bar feed pressure, the CNC1/PVA‐LA setup demonstrated a CO2 permeability of 20,522 Barrer and a selectivity of 33, making it suitable for low‐pressure biogas storage systems with lower energy requirements. [ABSTRACT FROM AUTHOR]

During storage, food undergoes transformations, often producing volatile nitrogen compounds known as total volatile basic nitrogen (TVB‐N), which serves as an indicator of food freshness. In this study, chitosan (CTS) was blended with polyvinyl alcohol (PVA) and incorporated with anthocyanins (ACNs) to monitor the quality changes in fish fillets over different time intervals. The results demonstrated that the presence of PVA in the CTS membrane enhanced light transmittance and reduced water absorption due to the reinforcement of the membrane structure through chemical interactions. In the freshness monitoring experiments, the CTS/PVA membranes exhibited an improved value of total color difference (ΔE), facilitating better detection of pH changes of the surrounding environment. Moreover, the ΔE value of the CTS/PVA film was observed to be quite similar to the value at pH 9 after 24 h and at pH 11 after 36 h when the fish fillet was stored at 25°C. In contrast, the ΔE value of the CTS/PVA film closely matched the value at pH 11 after 96 h of storage at 4°C. Additionally, the correlation between the generated TVB‐N and the ΔE values indicated a higher correlation coefficient (R2) for the composite membranes compared to the pristine CTS or PVA membranes. [ABSTRACT FROM AUTHOR]

Drugs with low water solubility comprise a significant proportion of pharmaceutical compounds. To control the release of these drugs, polymer thin‐film formulations with a physical hydrophobic barrier layer do not provide ideal release profiles. In this study, polymer carriers with hydrophilic polyvinyl alcohol (PVA) as the barrier layer are developed, and investigated the effect of the PVA film thickness on the release of hydrophobic molecules. Instead of an aqueous system, an oil‐based system is used to measure membrane permeability, and Nile Red is used as the hydrophobic model drug. PVA thin films are prepared with polycaprolactone as the supportive layer, which retained their permeability. In the limited thickness range investigated, PVA thin films exhibited thickness‐dependent permeability toward the hydrophobic model drug. [ABSTRACT FROM AUTHOR]

An electro- and optically favorable quaternary nanocomposite film was produced by solution-casting nickel oxide nanoparticles (NiO NPs) into polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT/PSS). Based on transmission electron microscopy (TEM) and X-ray diffraction (XRD) observations, the synthesized NiO NPs have a cubic phase and a diameter between 10 and 45 nm. The complexity and interactions observed through XRD patterns, UV–visible spectra, and FTIR measurements suggest that the NPs are not just dispersed within the polymer matrix, but are interacting with it, leading to enhanced dielectric properties and AC electrical conductivity. From 9 × 103 to 3.22 × 103 Ω, NiO NPs concentrations reduce bulk resistance Rb, indicating more linked conductive channels. The dielectric tests showed that polarized nanoparticles increased polarizability under electric field conditions. The incorporation of NiO NPs boosted DC conductivity from 1.25 × 10–6 to 5.64 × 10–5 S m−1. The mobility of NiO NPs boosts DC conductivity linearly with field frequency. These interactions can lead to improved electrical conductivity, energy storage capabilities, and overall efficiency of the nanocomposite, making it a promising material for various applications. [ABSTRACT FROM AUTHOR]

Various hydrogels have been explored to create minimally invasive microneedles (MNs) to extract interstitial fluid (ISF). However, current methods are time-consuming and typically require 10–15 min to extract 3–5 mg of ISF. This study introduces two spiral-shaped swellable MN arrays: one made of gelatin methacryloyl (GelMA) and polyvinyl alcohol (PVA), and the other incorporating a combination of PVA, polyvinylpyrrolidone (PVP), and hyaluronic acid (HA) for fast ISF extraction. These MN arrays demonstrated a rapid swelling ratio of 560 ± 79.6% and 370 ± 34.1% in artificial ISF within 10 min, respectively. Additionally, this study proposes a novel method that combines MNs with a custom-designed Arduino-based applicator vibrating at frequency ranges (50–100 Hz) to improve skin penetration efficiency, thereby enhancing the uptake of ISF in ex vivo. This dynamic combination enables GelMA/PVA MNs to rapidly uptake 6.41 ± 1.01 mg of ISF in just 5 min, while PVA/PVP/HA MNs extract 5.38 ± 0.77 mg of ISF within the same timeframe. To validate the capability of the MNs to recover glucose as the target biomarker, a mild heating procedure is used, followed by determining glucose concentration using a d-glucose content assay kit. The efficient extraction of ISF and glucose detection capabilities of the spiral MNs suggest their potential for rapid and minimally invasive biomarker sensing. [ABSTRACT FROM AUTHOR]

Definitions of microplastics and nanoplastics vary globally, but often with an explicit or implied reference to a hard or well-defined interface between particle and solution. This differentiates them from single molecules dissolved in solution. However, it is difficult to detect this difference at the nanoscale. This study uses Analytical Scattering techniques to compare the behaviour of water-soluble polymers like Polyvinyl Alcohol (PVA) and Polyethylene Glycol, with nano-sized Polystyrene beads. Dynamic Light Scattering and Small Angle X-Ray Scattering measured the conformation and size of soluble polymers and dispersed nanoplastics. Differentiating scattering profiles for water-soluble polymers and non-soluble polystyrene at the nano-scale were seen. PVA 18-88 (used in soluble detergent films) and PEG 8000 dissolved into single molecules, presenting a random coil conformation. They did not aggregate over time. Nano-Polystyrene beads showed hard particle characteristics. Atomic Force Microscopy confirmed these findings, visually distinguishing single flexible PVA molecules in solution from the rigid Polystyrene beads. This study highlights the effectiveness of scattering techniques in differentiating water-soluble polymers from micro or nanoplastics. They differentiate single dissolved molecule vs particle behaviour, and detect hard interfaces characteristic of particles at nano-scale. So they could provide a better science-based definition of micro- or nanoplastics. This is important, because single molecules in solution can be studied using recognized methods for environmental safety, and their features can open more pathways for environmental degradation. Finally, the results show PVA used in detergent films dissolves to single molecules, and does not form micro nor nanoplastics. [ABSTRACT FROM AUTHOR]