Copolymerization Of Styrene Research Articles

Raspberry-like particle-assisted breath figures method to simultaneously fabricate superhydrophobic surfaces with different adhesions

In this article we introduced a raspberry-like particle-assisted breath figures method to simultaneously fabricate superhydrophobic surfaces with different adhesions. Firstly, SiO2 particles were in situ generated on the surface of styrene copolymer microspheres to form raspberry-like composite particles, and then simply separated the products according to the distribution differences of particles with different structures in the reactor. Finally, the superhydrophobic surface was prepared by breath figures (BF) method. The hydrophobic surfaces prepared by the particles on the wall and bottom of the reactor showed distinct adhesion, the former showed a Cassie-Baxter state with a contact angle of 158° and a sliding angle of 3°, while the latter exhibited a Wenzel state with high adhesion to water droplets. By changing the amount of styrene copolymer microspheres added, the superhydrophobic surface adhesion could be transformed. Meanwhile, the solid-liquid contact mode and the height to width (H/W) of the pores have also been proved to be the key factors affecting the surface adhesion.

Determination of complex refractive index of plastics from ultraviolet to mid-infrared by ellipsometry

Plastic litter is a pervasive issue in the ocean, posing threats to both marine ecosystems and human health. In the field of marine remote sensing detection, one common method for detecting and identifying marine plastics is by analyzing their optical characteristics, specifically their spectral remote sensing reflectance. This reflectance is dependent on the complex refractive index of plastics. Therefore, understanding the complex refractive index, which is an intrinsic optical property of plastics, holds significant importance in marine plastics research. In this study, we utilized spectroscopic ellipsometry to measure the complex refractive index of 9 common ploymers including polymethyl methacrylate (PMMA), methyl methacrylate–styrene copolymer (MS), polyethylene (PE), poly (ethylene glycol-co-cyclohexane-1,4-dimethanol terephthalate) (PETG), polybutylene terephthalate (PBT), polyoxymethylene (POM), perfluoroalkoxy (PFA), acrylonitrile butadiene styrene (ABS), and styrene-acrylonitrile copolymer (SAN). In addition, we have expanded the complex range of refractive index measurements to include UV and MIR bands with wavelengths up to 32 μm. To ensure the reliability and accuracy of the measurements, experimental results for polycarbonate (PC) were compared with data from the existing literature. The variation of refractive index with wavelength is studied and the causes of absorption peaks in the infrared range are discussed. Furthermore, Considering the dispersion relationship and monomer composition of PMMA, MS, ABS and SAN plastics, a comparative analysis of plastics with commonly used monomers is conducted, and the influence of monomers on refractive index is discussed. Our study indicates that the presence of styrene monomers leads to an increase in the refractive index of plastics in the visible to near-infrared band, while the presence of butadiene monomers results in a decrease.The findings from this study provide fundamental data for future research on marine plastic remote sensing detection applications.

Global LC-MS/MS targeted metabolomics using a combination of HILIC and RP LC separation modes on an organic monolithic column based on 1-vinyl-1,2,4-triazole

The paper presents an LC-MS/MS-based approach to targeted screening of both polar and non-polar metabolites using a synthesized monolithic column which is a copolymer of styrene, divinylbenzene, and 1-vinyl-1,2,4-triazole. It was shown that this column in combination with eluents 20 mM (NH4)2CO3 + NH3 (pH = 9.8, eluent A) and ACN (eluent B) allows for separation of metabolites of different nature in two modes, HILIC and RP LC, and these methods are mutually complementary. A combination of analyses based on these two modes was proposed, allowing detection of about 400 metabolites in a total time of less than 30 min. Comparison of the developed method with those utilizing commercially available columns with sorbents of various types showed that it could provide a broader metabolite coverage. Using the developed approach, metabolomic screening of dried blood spots samples of mice exposed with X-ray was performed, and metabolites that could be considered as possible markers of irradiation exposure and organ tissue damage were detected. Analysis of marker metabolites revealed metabolic pathways that were altered by radiation exposure. Comparison of the results with literature data showed the effectiveness of the developed metabolomic screening approach.

Production of SBS Reinforced Polyester Composite: Characterization of Physical and Chemical Properties

In this study, dissolved styrene butadiene styrene (SBS) copolymer is homogeneously reinforced into orthophthalic unsaturated polyester (UP) resin. Polyester composite production is carried out with the help of methyl ethyl ketone peroxide (MEKP) and cobalt octoate (Co Oc) catalysts. The density, Shore D hardness, thermal conductivity coefficient, thermal stability, morphological surface structure, and chemical bond structure of the obtained composite have been examined. According to the results, SBS reinforcement decreases the density of the composite and increases the thermal conductivity coefficient. The addition of SBS at different weight ratios (1%, 3%, 5%, 7%, and 10% w/w) reduces both the hardness and thermal stability of the polyester composite. According to the test and analysis results, 5 wt.% SBS reinforced polyester composite production is determined as the optimum ratio. 7 wt.% and above SBS reinforcement negatively affect the physical and chemical properties of the obtained composite. For example, when 10 wt.% SBS reinforced composite is examined by scanning electron microscope (SEM), and irregular pores are observed in the surface morphology. Also, it is understood by Fourier transform infrared spectroscopy (FTIR) that there is a physical interaction between SBS and polyester and that no chemical bond is formed. The thermal decomposition behavior of the composite has been determined according to the decrease in the activation energy. As SBS ratio increases, it is understood that the thermal stability of the product obtained with the decrease in the activation energy of the polyester composite weakens.

Design and fabrication of superamphiphobic coating based on raspberry-like F–SiO2@PSA hybrid nanocomposite particles

Emulsifier-free polymerization was employed to prepare the submicron spherical PSA (the copolymer of styrene and acrylic acid), then SiO2 was grown on the surface of the PSA by sol-gel method to form F–SiO2@PSA particles. It was found that when styrene: acrylic acid = 2.5:1 and tetraethyl orthosilicate: PSA was between 2.17:1 and 6.38:1, a perfect raspberry-like structure could be obtained. The coating based on F–SiO2@PSA particles exhibited contact angles of 167.3 ± 1.4°, 152.1 ± 1.5°,150.3 ± 1.6°, 150.9 ± 1.6°, 142.2 ± 1.7°, 143.7 ± 1.5° and 146.6 ± 1.9° to water, diiodomethane, soybean oil, rapeseed oil, hexadecane, kerosene, and waste engine oil, respectively. The F–SiO2@PSA coating could reduce the adsorption of protein by 90% compared with the control surface. It was observed that bacteria and platelets could hardly adhere to the coating surface after 24 h of E. coli culture and 3 h of platelet-rich plasma immersion. The anti-adhesion to proteins, platelets, and bacteria will give the coating a promising application in the medical field.

Copolymerization of butadiene and styrene under the influence of n-butyllithium

It is known that styrene-butadiene copolymers having an increased content of 1,2-links of butadiene give tires a unique combination of good grip properties and low rolling resistance. Under conditions of severe operation, heat generation, and, therefore, rolling resistance of this rubber turned out to be less than that of polymers with a conventional structure. Compared to other rubbers, SSBR rubber with a high content of carbon black (mire than 50%) is highly economical. Lower heat generation in SSBR tires is a significant advantage over other rubbers and is preferable for long-term safety of the run even in desert conditions. The growing requirements for energy saving, safety of road transport, ecology, as well as a sufficient level of scientific research in the field of ionic polymerization of monomers were prerequisites for the creation of technology for obtaining solution copolymers based on dienes and vinyl aromatic monomers with special properties based on the mathematical model of the isothermal process of copolymerization of styrene and butadiene in an aliphatic solvent on the n-BuLi/mod catalytic system, which includes four chain growth reactions, two chain transfer reactions to a transfer agent, the concentration of which is recalculated. The calculation of the copolymerization constants of styrene and butadiene in hexane in the presence of the tested catalytic system is presented and the parameters of the obtained mathematical model are determined. Compliance with the optimal mode of conducting the polymerization process makes it possible to obtain rubber with specified physical and mechanical properties. The models presented in this paper take into account the most complex mechanisms of the copolymerization process, taking into account the hydrodynamics and heat transfer in the system, as well as the features of the real technological process. For the first time, the universal approach to solving the problem of obtaining SSBR rubber with a predictable set of properties is proposed. Based on mathematical modeling, laboratory experiments and optimization of the copolymerization process, the possibility of directed synthesis of functionalized DSSC rubber with the required physical and mechanical characteristics has appeared.

Study on the possibility of synthesizing oxygenates based on light pyrolysis resin using a modified ion exchange resin

Dialkyl ethers present potential additives to motor fuels. The study considers the possibility of obtaining oxygenates from light pyrolysis resin. The interaction of 75–90 °C fraction from light pyrolysis resin (LPR), having high content of high molecular weight unsaturated hydrocarbons, compared to other lighter fractions of LPR with a significant content of saturated hydrocarbons, and ethanol at different reagent ratios in the presence of a catalyst, Purolite CT-151 ion-exchange resin (sulfonated copolymer of styrene and divinylbenzene) modified with Na+, K+, Cu2+, Ca2+, Co2+, Ni2+ ions, is analyzed. The iodine value is chosen as the key parameter reflecting the content of unsaturated structures. The greatest decrease in the iodine value is observed for the ion exchange resin modified with cobalt ions, which is further used as the etherification catalyst. At 75–90 °C fraction:ethanol ratio of 0.5:1.5 and 60 °C, the yield of oxygenates reached 4.9% by weight.

A self-healing and anticorrosion epoxy coating based on the novel polymer filler containing a side-linked grafting 2-mercaptobenzothiazole

The healing mechanism of traditional self-healing coatings can be divided into “extrinsic” and “intrinsic” types according to the reactants, among which intrinsic restorations can be recycled multiple times and have great potential for applications. But epoxy resin is difficult to achieve intrinsic healing process through secondary bonding and reaction between polymers owing to the high chain rigidity and cross-linking density. In this study, a composite coating combining both “extrinsic” and “intrinsic” healing methods has been fabricated by adding a novel polymer filler (MBT-PGMS), which was synthesized via grafting copolymerization of glycidyl-methacrylate, styrene, methyl-methacrylate and 2-mercaptobenzothiazole (MBT). Multiple analytical techniques have been used to characterize the structure and properties of fillers, and the effect on the anti-corrosion performance and self-healing efficiency of epoxy coatings in 3 wt.% NaCl solution has been studied by electrochemistry measurements and mechanical analysis. Results indicated that the intact coating containing MBT-PGMS (MBT-PGMS/EP) showed prominent corrosion resistance during the immersion of 90 days. Once the coating was scratched, the impedance of MBT-PGMS/EP increased gradually with increasing the immersion time, and reached the optimal performance as the filler amount at 5 wt.%, while the impedance modulus was about 2.8 × 108 Ω cm2 after immersion for 144 h. A dynamic crosslinking model in MBT-PGMS/EP has been proposed to explain the self-healing mechanism.

Sorbent for HPLC based on copolymer of styrene and divinylbenzene with gold nanoparticles stabilized by eremomycin

Sorbent for HPLC based on copolymer of styrene and divinylbenzene with gold nanoparticles stabilized by eremomycin

Thermoplastic Elastomers for Wireless, Skin‐Interfaced Electronic, and Microfluidic Devices

AbstractWireless, skin‐interfaced electronic and microfluidic devices have the potential to replace wired, bulky, and cumbersome technologies for personal and clinical health monitoring, allowing care to extend from hospital settings to the home. For use on skin, these devices commonly employ silicone‐based thermoset elastomers (TSEs) as layers that encapsulate the electronics or serve as molded microchannels for biofluid (e.g., sweat) capture, storage, and analysis. Barriers to commercial adoption of such devices include difficulties in use of these elastomers in conventional practices for mass manufacturing. Their relatively high cost and inability to allow for recycling represent additional disadvantages. By contrast, thermoplastic elastomers (TPEs) are fully compatible with industrial‐scale manufacturing processes, low in cost, and recyclable. Like TSEs, TPEs are soft, stretchable, flexible, and optically transparent, while possessing other properties well‐suited for applications in wireless, skin‐interfaced devices. Herein, the characteristics, processing, and application techniques for three commercially available TPEs, including two thermoplastic polyurethanes as encapsulation layers for a wireless skin hydration sensor and one thermoplastic styrenic block copolymer for a microfluidic sweat analysis platform, are reported. The results demonstrate that TPEs can be effectively integrated into these classes of devices, as a compelling alternative to TSEs, as a mass‐manufacturable, sustainable materials option.

Ag triangle nanoplates assembled on PVC/SEBS membrane as flexible SERS substrates for skin cortisol sensing

Surface-enhanced Raman scattering (SERS) based on rigid substrates has been widely used in biomedical detection due to its high sensitivity and specificity. However, the tedious operation steps for preparing SERS rigid substrates limited their applications in real-world detection. Compared with general rigid substrate, the flexible substrate has the advantages of simple preparation and easy portability, which are suitable for rapid, wearable and personalized detection in the field of point-of-care test. Herein, the flexible SERS substrates employing copolymer were fabricated and used for detection of skin cortisol, a biomarker for evaluating psychological stress in sweat. Silver triangle nanoplates with sharp corner were used as enhanced particles, and transferred to polyvinyl chloride/styrene-ethylene-butene-styrene copolymer (PVC/SEBS) film through three-phase interface self-assembly. By adjusting the size of silver nanoparticles, the ratio of PVC to SEBS in the polymer film, and the number of transfers of self-assembled silver films, the enhancement effect of the flexible SERS substrate was maximized. In addition, functionalization of the flexible SERS substrate with cortisol antibodies is used to achieve specific detection of cortisol on the skin surface. Under the optimal conditions, the Raman peak intensities at 1268 and 1500 cm−1 of the cortisol had a good linear relationship with the logarithm of its concentration in the range of 10−7 to 10−3 M, and the detection limits were 5.47 × 10−8 M and 5.51 × 10−8 M, respectively. The flexible silver triangle nanoplates SERS substrate constructed by self-assembly in the three-phase interface has the characteristics of good specificity and high sensitivity, which has potential for transdermal cortisol wearable detection, providing a feasible method for the rapid evaluating psychological stress level.

Stress relaxation and thermal management in highly filled flexible styrene butadiene styrene copolymer‐tungsten composites for high‐energy radiation attenuation

AbstractA high loading of high‐density and high‐atomic‐number fillers are necessary to obtain desirable X‐ray attenuation characteristics from radiation shields. However, at high filler loadings, the mechanical and viscoelastic properties of polymers are severely impaired, posing a long‐term threat to the mechanical integrity and radiation protection, and the radiation shield temperature may increase after prolonged exposure to ionizing radiation, accelerating the aging of the polymer matrix. In addition, inadequate thermal conduction can make the user uncomfortable while using radiation shields for personal protection. Unfortunately, little attention has been paid to the viscoelastic, stress relaxation, and thermal conductivity‐related features of these densely loaded systems, despite the significant effect of these parameters on long‐term applications and user compliance. In the present work, two different styrene butadiene styrene (SBS) copolymers were used to develop SBS‐tungsten (W) composites. At 500 phr W loading, significant attenuation of X‐rays was achieved along with good tensile strength and elongation at break. The results indicate that the concentration of styrene in the SBS and W loading substantially affected the attenuation, mechanical and rheological properties, and tensile stress relaxation rates. The thermal conductivity increased by >100%, and after gamma irradiation, faster cooling was observed in the W‐loaded composites beyond 300 phr of W loading. The 40% styrene composite demonstrated superior heat transfer at high W loadings owing to the better dispersion and distribution of the W filler in the SBS matrix. Rheological results showed that SBS‐W composites with 30% styrene had a more pronounced Payne effect than those with 40% styrene. Stress relaxation and morphological analyses also revealed changes in the W dispersion in the SBS matrix depending on the styrene content.

Removal of Molybdate Ions in Water on a Newly Synthesized Imidazolium‐based Poly (ionic liquid)

AbstractThe natural biological water system has been seriously damaged due to the discharge of wastewater containing too much molybdenum, endangering the life and health of animals and plants. Imidazolium‐based poly (ionic liquid) was synthesized by grafting copolymers of styrene and 1‐(chloromethyl)‐4‐vinylbenzene into N‐methylimidazole, N‐ethylimidazole and N‐propyl imidazole, followed by characterization with the use of nuclear magnetic resonance spectrometer and Fourier transform infrared spectrometer. How the Imidazolium‐based poly (ionic liquid) could recover MoO42− from sewage was investigated. The pH, reaction temperature, reaction duration, adsorbent dose, and interfering ions were all tuned for MoO42− adsorption conditions. Nitric acid can regenerate the Imidazolium‐based poly (ionic liquid) loaded with MoO42−. Both the adsorption kinetics and the adsorption isotherm exhibit good agreement with the quasi second‐order kinetic model and the Langmuir isotherm model, respectively.Imidazolium‐based poly (ionic liquid) have a special reusability when compared to polyaniline‐modified bentonite, iron‐based nanomaterials, and γ‐Fe2O3 nanomaterials. The results reveal that Imidazolium‐based poly (ionic liquid) has a strong recovery effect on trace molybdenum from wastewater, which makes it an effective adsorbent with industrial application value.

Novel Adsorbents for the Determination of Amino Acids in Soil Extracts by Hydrophilic Interaction Liquid Chromatography with Mass Spectrometric Detection

Adsorbents based on various substrates—silica and a copolymer of styrene with divinylbenzene—are developed for the determination of amino acids by hydrophilic interaction liquid chromatography—mass spectrometry. The optimal version of the structure of the functional layer in two series of the obtained stationary phases was chosen, which provides the best hydrophilization for each substrate. Retention mechanisms were studied and the conditions for the mass-spectrometric detection, separation, and determination of 16 amino acids were chosen. The applicability of the obtained adsorbents and a method for determining amino acids for the analysis of soil extracts were estimated.

Half-Sandwich Rare-Earth metal complexes bearing 4,5,6,7-Tetrahydroindenyl ligands for highly Syndiospecific (Co)Polymerization of styrene

As Cp-derived ligands, substituted 4,5,6,7-tetrahydroindene (THI) ligands with tunable steric bulk have been synthesized, and their ligated half-sandwich rare-earth metal complexes were also sucessfully prepared and tested for styrene (co)polymerization. In conjunction with [Ph3C][B(C6F5)4], the THI-ligated scandium complexes exhibited high catalytic activity for highly syndiotactic polymerization of styrene (>99% rrrr). THI3Me-Sc/[Ph3C][B(C6F5)4] binary system also promoted the copolymerization of styrene and isoprene/butadiene by both the concurrent addition and sequentical addition of monomers, affording the copolymers with block microstructure as deterimined by NMR (1H and 13C) spectra. The huge difference in reactivity ratios betewen styrene and isoprene/butadiene (rIP / rSt = 31.1 and rBD / rSt = 173.6) revealed in kinetics investigation further proved the predominantly block structure of resultant copolymers.

Extraction of natural fibers of Catole coconut (Syagrus Cearensis): Application as reinforcing filler in polypropylene‐based composites

AbstractPolypropylene/Syagrus Cearensis fiber composites compatibilized with polypropylene‐graft‐maleic anhydride (PP‐g‐MA) and styrene(ethylene‐butylene)‐styrene copolymer (SEBS‐g‐MA) were successfully produced using a co‐rotating twin‐screw extruder followed by injection molding. The composites were characterized by X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The mechanical properties were determined by Izod impact and tensile testing. Thermal properties were obtained by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). Heat deflection temperature (HDT) was determined to study the thermomechanical properties of the composites. XRD and DSC indicated the presence of two polypropylene polymorphs: α and β. The unmodified PP/Fiber composites showed an incompatible behavior, presenting low fiber/matrix interaction and poor interfacial adhesion. The poor compatibility led to low elongation at break and impact strength but high tensile strength. PP‐g‐MA coupling agent promoted some adhesion to the PP/fiber interfaces but not enough to improve the impact strength. The composites with PP‐g‐MA exhibited improved tensile modulus and strength. The enhanced PP/fiber interfacial interaction promoted by SEBS‐g‐MA generated a better interplay of mechanical properties, improving impact strength and elongation at break while preserving the elastic modulus and tensile strength. In general, the fibers enhanced the thermomechanical stability of PP, as evidenced by higher HDT values.

Plastiglomerates from uncontrolled burning of plastic waste on Indonesian beaches contain high contents of organic pollutants

This study reports on plastiglomerate and other new forms of plastic pollution in the tropical marine continent of Indonesia. Twenty-five samples were collected from an island beach in the Java Sea where plastiglomerate, plasticrusts, and pyroplastic were formed by the uncontrolled burning of plastic waste. The most common plastic types were polyethylene and polypropylene (PE/PP), as shown by ATR-FTIR spectroscopy. However, acrylates/polyurethane/varnish (PU) and a copolymer of styrene and acrylonitrile were found as well. This suggests that plastiglomerates can form from a wider variety of plastic polymers than previously reported. FTIR analysis also indicates thermo-oxidative weathering, making the charred plastic more brittle and susceptible to microplastic formation. A subset of the samples was analyzed for associated chemical contaminants. One plastiglomerate with a PU matrix showed high concentrations of phthalates. All samples had high concentrations of polycyclic aromatic hydrocarbons (PAHs), likely due to the burning of the plastic in open fires. The burning leads to a change in the physical and chemical properties of the plastics contained in the plastiglomerates. Plastiglomerate and plastic waste of similar origin are therefore often more weathered and contaminated with organic pollutants than their parent polymers. The highest PAH concentration was found in a plastitar sample. Plastitar is defined as an agglomerate of tar and plastics that adheres to coastal rocks. In contrast, our study documents a more mobile, clastic plastitar type. This clastic plastitar could pose an additional ecological risk because of its mobility. These new types of plastic pollution could be an important vector for chemical contamination of nearby coastal habitats such as coral reefs, seagrass meadows, and mangroves.

Facile access to redox responsive self-healing coating materials via living cationic block copolymerization of styrene and 2-chloroethyl vinyl ether

Poly(alkyl vinyl ether)-based functional copolymers have wide applications in many high-tech areas. However, their synthesis is still challenging which limits their applications. This article describes the synthesis of an unprecedented redox-responsive polystyrene-block-poly(2-thioethyl vinyl ether) (PSt-b-PTEVE) diblock copolymers via sequential “water tolerant” cationic polymerization of St and CEVE, followed by post-polymerization transformation of the pendant -CH2CH2Cl functionalities of PCEVE segment to -CH2CH2SH functionalities. The initiating system enabled controlled cationic polymerization of styrene (St), yielding well-defined PSt (at least up to 22500 g/mol) with relatively low dispersity (Đ ≤ 1.36) and polystyrene-block-poly(2-chloroethyl vinyl ether) (PSt-b-PCEVE) diblock copolymers with acceptable dispersity values (Đ ≤ 1.38) thereof, demonstrating high chain-end fidelity. The controlled character of the cationic polymerization reaction was confirmed by linear kinetic plots, linear increase of Mns (with low Đs) and synthesis of PSts of changing Mns simply by varying initial [St]0/[Initiator]0 feed ratio. The synthesized PSt-b-PTEVE diblock copolymers exhibited redox responsivity and self-healing behaviour. The self-healing property of the PSt-b-PTEVE diblock copolymer was studied by optical microscopy. For this, first, a mechanical cut was introduced in the cross-linked PSt-b-PTEVE thin films and then images were taken at regular intervals to investigate the healing. These promising PSt-b-PTEVE diblock copolymers might have potential applications in many emerging areas, including functional coating.

Polymeric Surfactants Bearing Divalent Carboxy Pendants for Stable Color Dispersions with High Redispersibility

Inkjet printing of ink requires dyes or pigments insoluble in water but uniformly dispersing as fine particles for a long period. In addition, redispersibility after solidification by solvent vaporization around the jetting heads is also important for performance. In this study, thus, a series of amphiphilic copolymers were prepared for a dispersant of inkjet using reversible addition fragmentation chain-transfer copolymerization of styrene (St), benzyl acrylate (BnA), and phenoxyethyl acrylate (PEA) as a hydrophobic monomer with acrylic acid (AA) and itaconic acid (IA) as a hydrophilic monomer. To understand the fundamental properties and potentials as a polymer dispersant, the surface parameters and rheology of the copolymers and their color dispersions in aqueous media were investigated. The aqueous solutions were typical Newtonian fluids, whereas the color dispersions were non-Newtonian fluids with shear-thinning properties and yield values ranging from 0.57 to 1.04 Pa. Although the surface parameters, such as surface tension (γ), molecular occupied area (Amin), and zeta potential (ζ), did not show clear correlation with polymer structures, their behaviors as a dispersant were significantly different. The color dispersants containing the copolymer of St or BnA as a hydrophobic monomer and IA and AMPS as hydrophilic monomers exhibited sufficient redispersion both for yellow and cyan inks, even after the aging test at 60 °C for 5 days, whereas other copolymers did not exhibit such superior performances. In addition, the color dispersions of the copolymer of St, IA, and AMPS (St-IA-AMPS) showed lower viscosity and yield value and became closer to Newtonian fluid compared with that of St, AA, and AMPS (St-AA-AMPS). Thus, St-IA-AMPS provided good redispersibility and avoided sedimentation. These results suggest that the most suitable dispersant for inkjet inks among the polymers investigated was the copolymer of St, IA, and AMPS.

First evidence of microplastic ingestion in the ocean giant sunfish (Mola mola)

Mola mola is the largest teleost inhabiting our ocean and the presence of microplastics (MP) in this flagship species was, before this study, never described. Thus, this investigation focused on analysing MP ingestion in 53 ocean giant sunfish in the Northeast Atlantic Ocean. A total of 116 MP were found in 79% of the specimens, with a median of 1 MP.ind−1, ranging from 0 to 11 MP.ind−1. Seasonal differences were observed, with more fibers registered in specimens caught in autumn. Among the different size classes observed, the smallest category (<300 μm) was the most frequent (43%). Blue (43%) was the most prevalent color, followed by green (29%) and black (10%). The majority of fragments were styrene acrylic copolymer (53%), while most fibers were rayon (78%). These findings emphasize that the ocean sunfish population crossing the southern waters of Portugal is exposed to microplastic pollution and highlight the need for effective management policies to address plastic pollution in marine ecosystems.