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Cement Asphalt Mortar (CAM) is widely applied in infrastructure, particularly in railways, bridge expansion joints, and pavements, due to its combination of cement's load-bearing capacity and asphalt's flexibility. Conventional CAM formulations, however, often encounter challenges such as extended setting times, high shrinkage, and limited durability under extreme environmental conditions. This study addresses these limitations by integrating bio-oil and polymer additives to enhance both the sustainability and performance of CAM mixtures. CAM mixtures were evaluated with cement-to-asphalt emulsion (C/AE) mass ratios of 75:25 and 50:50, incorporating bio-oil contents of 2% and 4% by mass and latex–acrylic polymer proportions ranging from 1% to 2% by mass. The optimized mix design, with a 75:25 cement-to-asphalt emulsion (C/AE) mass ratio, 2% bio-oil, and 1.5% polymer, improved flowability by 25%. This formulation achieved a flow diameter of approximately 205 mm and reduced the flow time to 72 s. Compressive strength tests indicated that this formulation reached an early-stage strength of 10.45 MPa (a 20.8% improvement over the control) and a 28-day strength of 24.18 MPa. Thermal stability tests at 45 °C demonstrated that the optimized CAM retained 86.6% of its compressive strength, compared to a 25% reduction in unmodified mixtures. Chemical resistance assessments in 5% sulfuric acid and 5% sodium hydroxide solutions showed strength retention of 95.03% and 91.98%, respectively, outperforming control mixtures by 17% and 13%. SEM examination revealed a dense, cohesive microstructure, reducing shrinkage to 0.01% from 0.15% in the control. These findings underscore the potential of bio-oil and latex–acrylic polymers to improve the performance and sustainability of CAM mixtures, making them well suited for resilient, rapid-setting infrastructure applications. [ABSTRACT FROM AUTHOR]

Purpose: Employing polymer additives is an effective strategy to realize the manipulation of polymorphic transformation. However, the manipulation mechanism is still not clear, which limit the precise selection of polymeric excipients and the development of pharmaceutical formulations. Methods: The solubility of cimetidine (CIM) in acetonitrile/water mixtures were measured. And the polymorphic transformation from CIM form A to form B with the addition of different polymers was monitored by Raman spectroscopy. Furthermore, the manipulation effect of polymers was determined based on the results of experiments and molecular simulations. Results: The solubility of form A is consistently higher than that of form B, which indicate that form B is the thermodynamically stable form within the examined temperature range. The presence of polyvinylpyrrolidone (PVP) of a shorter chain length could have a stronger inhibitory effect on the phase transformation process of metastable form, whereas polyethylene glycol (PEG) had almost no impact. The nucleation kinetics experiments and molecular dynamic simulation results showed that only PVP molecules could significantly decrease the nucleation rate of CIM, due to the ability of reducing solute molecular diffusion and solute–solute molecular interaction. A combination of crystal growth rate measurements and calculations of the interaction energies between PVP and the crystal faces of CIM indicate that smaller molecular weight PVP can suppress crystal growth more effectively. Conclusion: PVP K16-18 has more impact on the stabilization of CIM form A and inhibition of the phase transformation process. The manipulation mechanism of polymer additives in the polymorphic transformation of CIM was proposed. [ABSTRACT FROM AUTHOR]

The construction industry's quest for sustainable materials drives the investigation into novel additives to enhance clay brick performance. High-Density Polyethylene (HDPE) and Polyethylene Terephthalate (PET) polymers hold promise, yet their impact on porosity and water absorption in varying grain sizes remains underexplored. They incorporated HDPE and PET polymers in diverse proportions and grain sizes into unfired clay bricks, examining the resulting changes in porosity and water absorption through bulk density measurements, microscopy, and capillary water absorption coefficient analysis. Polymer additives, particularly d=1 mm PET, significantly reduce porosity, enhancing brick performance. The capillary water absorption coefficient establishes a direct link between polymer content and increased porosity. As polymer proportions rise, so does brick porosity, offering a nuanced understanding of the relationship. SEM analysis highlights PET mortar's consistent, lowporosity structure, underscoring the potential for sustainable construction materials. This study provides crucial insights for future developments in eco-friendly construction practices. In summary, the integration of HDPE and PET polymers presents a promising avenue for advancing sustainable construction materials, offering a balance between enhanced performance and environmental considerations. [ABSTRACT FROM AUTHOR]

Plastics are remarkable due to their chemical and physical properties and are used in many fields, especially food packaging. To produce the packages, during the manufacturing processes, an array of additives such as plasticisers, stabilisers, antioxidants, lubricants, and pigments is required. Unfortunately, most additives can migrate and contaminate the food they are intended to hold and preserve. Identifying potential migrants is likely the only way to gain knowledge, improve the manufacturing processes, and assess potential health risks related to the migration of additives and their degradation products to food media. Therefore, in this study, commercial polyethylene packages were investigated using validated liquid chromatography with tandem mass spectrometry (LC–MS/MS) method to reliably quantify the content of the antioxidants Irganox 1010 and Irgafos 168-ox and their migration levels to food simulants representing foods having hydrophilic and lipophilic properties. The results revealed the highly varying amount of antioxidants in different types of polyethylene food contact materials. [ABSTRACT FROM AUTHOR]

The collision of drops of water and elastic liquids with a thin cylinder (fiber) has been studied. Aqueous solutions of polymers were used as elastic liquids, which simulated the rheological behavior of oral fluid—the main carrier of infections by airborne drops. Water as a Newtonian fluid was investigated to identify the elastic effects when comparing the collisions of Newtonian and non-Newtonian fluids—water and polymer solutions. The flight path of the drop and the cylinder axis are mutually perpendicular. Attention is focused on the difference between the collisions of water drops and drops of elastic liquids. In the experiments, the diameter of the drop was 3 mm, and the diameter of the horizontal stainless-steel cylinders was 0.4 and 0.8 mm. Drops were formed by the slow flow of liquid from a vertical stainless-steel capillary with an outer diameter of 0.8 mm, from which the drops were periodically separated under the influence of gravity. The velocity of the drop before the collision was determined by the distance between the end of the capillary and the target (cylinder); in the experiments, this distance was 5, 10, and 20 mm. The velocities of falling drops before impact were estimated in the range of 0.2–0.5 m/s. The collision process was monitored using high-speed video recording methods with frame rates of 240 and 960 Hz. Water and aqueous solutions of polyacrylamide with a molecular weight of 11 million and concentrations of 100 and 1000 ppm were used as test liquids. Experiments have shown that, depending on the height of the drop and the concentration of the polymer, various drop collision scenarios are possible: (1) short-term rebound of the drop from an obstacle, (2) braking and stopping the drop on the obstacle, (3) flow of the drop around a cylindrical obstacle while maintaining continuity and continuing free flight, (4) disintegration of the drop into two secondary drops, each with its own history of subsequent flight. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs) comprising zinc anodes hold intrinsic safety and high energy density ideally for distributed and large‐scale energy storage, thus have generated intriguing properties and increasing research interests. Unlike organic batteries, AZIBs require different, sometimes even opposite design principles and preparation strategies in solvent, electrolyte, and separator. This is especially true for the polymer materials that are widely used as critical components in stabilizing metal anodes and functioning as high‐performance safe cathode materials. This review discusses the explicit compositional and structural requisite of polymeric components in AZIBs, with an emphasis on the exclusive molecular structure–property relationship that governs the stability, reversibility, and capacity of these devices. The usage of polymers is classified into five categories aligning with the primary architecture of AZIBs: separators, additives, hydrogel electrolytes, coatings, and electrode materials. The most recent advances in the structure/property interplay of polymers by novel synthesis and preparation techniques targeting stable AZIBs are summarized and discussed. The challenges and perspectives of multifunctional polymers in developing high‐performance AZIBs are also proposed. [ABSTRACT FROM AUTHOR]

One of the major obstacles to Nigeria's techno-economic development has been a lack of good road infrastructure. Despite a large deposit of natural bitumen in the form of semi-liquid and bitumen sand, the reliance on imported bitumen/asphalt for road construction and maintenance in Nigeria has reduced road coverage and quality. To use local bitumen as a binder in pavement construction, an efficient upgrading process is required using polymers, nanomaterials, and other chemical additives. However, the selection of an appropriate modifier depends on many factors including the origin, elemental and chemical composition of bitumen. This review presents vital properties of Nigerian bitumen extracted from oil wells and tar sands with the view to identifying potential additives as solutions for its upgrading. Based on predefined selection criteria, we conducted a systematic review of the literature. We gathered information on the current state of knowledge about the major issues encountered during the polymeric modification of bitumen. In addition, data on existing practices used by various road researchers to address such issues was gathered. Effort was made to review waste packaging polymers and plastics for possible utilization to ensure sustainable pavement infrastructure in Nigeria. The results of this review showed relatively little information on Nigerian bitumen upgrading. Many authors have investigated different polymer additives on asphaltic bitumen sourced from different countries and the results has pointed to the capability of polymeric modification to improve some of the properties of bitumen. A knowledge gap however, exists in the optimization of polymer dosage, and characterization of bitumen at the SARA level to aid the understanding of the effects of polymeric modification and mechanisms involved during the pavement degradation. Additionally, it has been challenging to generalize the effects of different polymers due to the variation of bitumen properties from different sources. This review identifies the potential for upgrading Nigerian bitumen using polymer additives, the potential of waste plastics, crumb rubbers, and packaging waste materials as alternative and sustainable additives also highlighted.

A common approach to enhance the stability of metal halide perovskites (MHPs) implemented in optical and optoelectronic devices is to incorporate polymer additives into the perovskite layer. A β‐(1,4) cellulose oligosaccharide (COS) synthesized by mechanocatalytic depolymerization of cellulose has been incorporated to films of the BA2MA4Pb5I16 (BA = n‐butylammonium and MA = methylammonium) two‐dimensional (2D) Ruddlesden‐Popper (RP) hybrid perovskite. Scanning Electron Microscopy (SEM) images displayed a three‐fold reduction of the 2D RP perovskite grains (≈30–40 nm), close to the quantum confinement scale. The analysis of the dark J–V curves of single carrier devices by using the space charge limited current (SCLC) method resulted in a rise of the defect concentration. A notable 14‐fold increase in the photoluminescence (PL) signal at high COS content is detected. Moreover, the analysis of the temperature dependence PL measurements (80–300 K) resulted in a larger exciton binding energy, Eb = 180 to 370 meV, at high COS content. Light emitting diodes of the 2D RP perovskites (PeLEDs) are fabricated w/o the COS compound. The stability test performed under operation (5 V) displays 20 times higher operational lifetimes at high COS content while the luminance is also increased in the devices with the COS compound. [ABSTRACT FROM AUTHOR]

Surface morphology of lead deposits from H2SiF6-PbSiF6 electrolyte containing an animal glue was investigated by means of the periodic galvanostatic electrolysis and SEM-EDS observation. The weight average molecular weight of the glue was also determined with the static light scattering measurement. The temporal changes of the overpotential and the weight average molecular weight were discussed in terms of the elapsed time after preparing the electrolyte which contained 100 g∙L−1 of H2SiF6 and 100 g∙L−1 of Pb(II) and in which the initial concentration of the glue (Cglue) was 0–10.0 g∙L−1. The dendritic growth of lead deposits was observed from the electrolyte of Cglue = 0 g∙L−1 in the galvanostatic electrolysis where the cathodic current density and the electrolyte temperature was −150 A∙m−2 and 40 ℃, respectively. Smooth and dense lead deposits were obtained in the electrolyte of Cglue = 0.5–5.0 g∙L−1 when the elapsed time τ = 0 d. The surface of the deposits gradually became rough with increasing τ in the electrolyte of Cglue = 0.1–1.0 g∙L−1. On the other hand, nodules or bearded deposits were observed on the deposits obtained in the electrolyte of Cglue = 5.0 g∙L−1 when τ = 1–2 d. After this, the surface became smooth with the further increase of τ. The change of the weight average molecular weight of the glue (Mr,w) with τ was described with the equation, 1/(Mr,w)τ = 1/(Mr,w)0 + k′τ, in the electrolyte containing 100 g∙L−1 of free H2SiF6 and 100 g∙L−1 of Pb(II) at 40 ℃. The k′ value was evaluated to be 5 × 10−9 min−1 in the electrolyte of Cglue = 1.0 g∙L−1 and 6 × 10−9 min−1 in the electrolyte of Cglue = 10.0 g∙L−1.

The low cost and scalability advantages of printable mesoscopic perovskite solar cells (p‐MPSCs) are impaired by the issue of limited power conversion efficiency (PCE). Herein, the PCE of p‐MPSCs is improved by introducing the polymer additive polyacrylonitrile (PAN) into the formamidinium (FA)‐based perovskite for crystallization and defect modulation. PAN forms hydrogen bond and coordination bond with halide perovskite through its C≡N group. Such interactions improve the crystallization and filling of FA‐based perovskite in the mesoscopic scaffold and bring a long carrier lifetime by passivating defects. The synergy improves the PCE of p‐MPSCs from 16.80% to 18.33%. Meanwhile, the hydrophobic nature of PAN enhances the device's resistance against moisture. This work demonstrates that the polymer additive is a promising choice for breaking the PCE limit of p‐MPSCs. [ABSTRACT FROM AUTHOR]

Migration is a known phenomenon defined as the partitioning of certain chemical compounds from plastic food packaging into food and has been intensely investigated in recent years. Due to outstanding chemical and physical properties plastics are used in many fields. Polypropylene and polyethylene are extensively used polymers because of their chemical resistance, high tensile strength and low density. To improve the properties of the plastics, additives such as plasticizers, stabilizers, antioxidants, lubricants, pigments and others are required to be added. However, they can migrate from the plastics into the food and contaminate it during production or storage. Therefore, the aim of this study was to investigate commercial polypropylene and polyethylene packages to determine what most often used additives and degradation products of the food packages can migrate to food. After the initial identification of plastics by Fourier-transform infrared spectrometry, the determination of cadmium, chromium, lead and mercury was carried out by atomic absorption spectrophotom-etry. To evaluate possible volatile and semi-volatile organic compounds thermal desorption gas chromatography coupled with mass spectrometry was used. The results revealing the presence of different potential organic compounds and metals emitted during the degradation process of different types of food contact materials are discussed. [ABSTRACT FROM AUTHOR]

Abrasive Water Jet Machining (AWJM) is an advanced machining process that has a variety of applications, including machining of hard-to-machine materials, drilling, milling, coating removal, polishing, etc. They are attractive because of their versatility, absence of heat-affected zones, low thermal-distortions, low cutting-forces, and environment-friendly nature. However, use of plain-water in AWJM poses some problems due to lack of jet coherence, poor suspension characteristics, and unsatisfactory performances in submerged-cutting and cutting of hollow surfaces. Countering these problems appropriately can lead to better cutting performances in terms of material removal rate, depth of cut, kerf-width, and kerf-taper. It can be achieved with addition of some additives in abrasive water-jet. These additives are mostly polymers of high molecular mass, which increases viscosity, suspension capability, and stability of jet, while reducing drag. In addition to AWJM, the effect of polymeric-additives in other water-based jets like Abrasive-Slurry-Jet (ASJ), High-pressure ASJ, etc. are also discussed. Therefore, this study aims to identify and list of different additives that are used in AWJM and other water-jet-based machining-processes over a past few decades, and to provide a run-through on their performances. It can provide the significant information to researchers working in fields related to waterjets. [ABSTRACT FROM AUTHOR]

Contact lens materials include polymers that are ionized in the ocular pH condition and are susceptible to protein deposition due to their surface characteristics. Herein, we investigated the effect of the electrostatic state of the contact lens material and protein on protein deposition level using hen egg white lysozyme (HEWL) and bovine serum albumin (BSA) as model proteins and etafilcon A and hilafilcon B as model contact lens materials. Only HEWL deposition on etafilcon A showed a statistically significant pH-dependency (p < 0.05); protein deposition increased with pH. HEWL showed a positive zeta potential at acidic pH, while BSA showed a negative zeta potential at basic pH. Only etafilcon A showed a statistically significant pH-dependent point of zero charge (PZC) (p < 0.05), implying that its surface charge became more negative under basic conditions. This pH-dependency of etafilcon A is attributed to the pH-responsive degree of ionization of its constituent methacrylic acid (MAA). The presence of MAA and its degree of ionization could accelerate protein deposition; more HEWL deposited as pH increased despite the weak positive surface charge of HEWL. The highly negatively charged etafilcon A surface attracted HEWL, even overwhelming weak positive charge of HEWL, increasing the deposition with pH. [ABSTRACT FROM AUTHOR]

A new method has been developed for the estimation of an antistatic agent glycerol monostearate (GMS) in polypropylene (PP) over gas chromatography coupled with flame ionization detector (GC-FID). In the present work, selection of suitable sample specimen, sample weight, solvent mixture, extraction time, and temperature have been identified for the extraction of GMS in the PP resin. In-house polypropylene pellet has been used for study and the GMS extorted into n-hexane-ethyl acetate and quantified using GC-FID over 100% Dimethyl polysiloxane column. The method limit of detection is 1 mg/L and the limit of quantification is 5-750 mg/kg in PP resin with a correlation coefficient greater than 0.999. This method is accurate and has not found any interference with other co additives used in the propylene. [ABSTRACT FROM AUTHOR]

As a potential candidate for next‐generation energy storage systems, Li–O2 batteries (LOBs) with their attractive theoretical energy density have triggered great interest. However, tough issues of sluggish oxygen reduction reaction/oxygen evolution reaction (ORR/OER) kinetics, poor rechargeability, superoxide‐derived side reactions, and Li‐metal corrosion in LOBs limit their practical applications. Herein, a poly(2,2,2‐trifluoroethyl methacrylate) (PTFEMA) additive is introduced into the typical electrolyte, giving superior cycling performance to LOBs. Enabling strong solvation of Li+, PTFEMA regulates a uniform Li+ flow at the cathode and anode sides of LOBs. Induced by homogeneous Li+ flux and favorable adsorption with superoxide species, PTFEMA promotes superoxide transformation in the ORR and inhibits superoxide‐induced parasitic reactions. Uniform Li+ flux gives evenly‐distributed Li2O2 that can be completely decomposed during OER. In addition, PTFEMA protects Li‐metal against corrosion from O2, superoxide, and byproducts shuttle. Hence, accelerated ORR/OER kinetics, facilitated rechargeability, suppressed superoxide‐derived side reactions, and well‐protected Li‐metal can be simultaneously realized with PTFEMA, resulting in significantly enhanced electrochemical performance of LOBs. This electrolyte engineering involving facile multifunctional polymer additives provides a practical alternative to complex componential optimization toward commercial LOBs and gives insight to the understanding of uniform Li+ flux on reaction kinetics and reversibility. [ABSTRACT FROM AUTHOR]

The use of complex modifiers for cement-concrete mixtures and concretes is becoming increasingly popular in modern materials science. The paper presents studies of the effect of a polymer additive structured with carbon nanomaterial on the physical and mechanical characteristics of cement-concrete mixtures. IR spectroscopy and thermogravimetry revealed that the use of carbon nanomaterial significantly changes the structure of cement-concrete mixtures. As a result of the fact that high-strength nanomaterial is the center of crystallization of cement stone formations, a denser reinforced microstructure is formed, which significantly increases the strength characteristics of cement-concrete mixtures. Inclusion in the composition of cement-concrete mixtures of polymer complex additives leads to higher and longer plasticization, which plays an important role in the production of monolithic products. It is established that in the presence of a complex modifier (polymer additive structured with carbon nanotubes) the crystal structure of calcium hydrosilicates is compacted, which causes high physical and mechanical characteristics of modified cement-concrete mixtures. It is experimentally shown that the additive acts as an accelerator of hardening and hardening of cement paste, as well as increases its strength characteristics. In general, for all cement-concrete mixtures in this study there is a water-reducing effect of the additive. Water consumption decreases by 5 wt. %, while the strengThincreases by 19%. Formulations of cement-concrete mixtures modified with polymer additives, structured carbon nanotubes, with high performance characteristics have been developed. [ABSTRACT FROM AUTHOR]

Friction drag is a nonnegligible matter when relative motion happens between solid and liquid phase, which brings many inconveniences in ship navigation, fluid transportation, microfluid devices, etc. Thereby various methods have been developed focusing on friction drag reduction. In this article, a review of several widely studied drag reduction methods is given, specially, their advantages and limitations in practical applications are discussed. Besides, a comparison of different methods is made and the development prospect of drag reduction is concluded. [ABSTRACT FROM AUTHOR]

The mechanism of contact between liquid droplets and hot surfaces is important and attracts many researches recently. Herein, we experimentally investigate the contact of Newtonian and viscoelastic droplets between gradually heated surfaces at low Weber numbers, which has not been explored. To present a detailed analysis of contact line dynamics, experiments were performed across a surface temperature ranging boiling conditions to above Leidenfrost temperature (100°C−300°C), while various impact phenomena with increasing surface temperature have been observed for Newtonian and viscoelastic droplets. We demonstrate that the polymer additives significantly affect the dynamic contact angle and contact radius on heated hydrophilic surface. In the Leidenfrost regime, the increased velocity causes considerable reduction on contact time of water droplets, especially at the breaks-up mode. However, it does not influence the contact time of impinging polymer droplet. Aqueous polymer droplets with high molecular weight and high concentration suppress secondary atomization, splashing and break-up, but promote droplet foaming and the generation of viscoelastic filaments. The results illustrate how the polymer additives, surface temperature and impact velocity affect the impact outcomes, and original impact phase diagrams are proposed finally.

Drag reduction has constantly received great attention due to its extensive range of applications in fluid transportation and vehicle industries. The vital role of two different additive and non‐additive techniques (polymer additives and superhydrophobic surfaces) to reduce the drag force experienced by underwater vehicles, fluid flow through pipes, ducts, open or closed channels, and other wall‐bounded laminar and turbulent flows is highlighted. Reducing the drag resistance can significantly enhance the performance of immersed vehicles and results in saving the energy consumed on a large scale. The progress in theoretical modeling, experimental and computational studies of both techniques are reviewed, together with the surface design, wettability, and influence of the roughness factor of superhydrophobic surfaces and the effect of polymer drag‐reducing agents for wall‐bounded flows and multiphase flows. General formulations, potential applications, and major issues involved in the aforementioned approaches are summarized. [ABSTRACT FROM AUTHOR]

The polymer additives may migrate out from polymer plastics into foods and drinks and their potential risk should not be ignored. In this study, amino group modified magnetic mesoporous silica microspheres were prepared by an in situ method. The magnetic microspheres as adsorbent of magnetic solid-phase extraction (MSPE) were coupled with high performance liquid chromatography (HPLC) to determine nine kinds of polymer additives including antioxidants and ultraviolet absorbers. An excellent linearity (0.9999 ≥ R2 ≥ 0.9994) was at the range of 1.25–1000 ng/mL under optimized conditions. The limits of detection (LODs) and quantification were 0.01–0.09 ng/mL and 0.02–0.30 ng/mL, respectively, for the nine polymer additives, which was lower than those previously reported. This method can be used for the quantitative determination of the migration levels of seven kinds of polymer additives in real foods and drinks packed with plastics. [ABSTRACT FROM AUTHOR]

One of the major obstacles to Nigeria's techno-economic development has been a lack of good road infrastructure. Despite a large deposit of natural bitumen in the form of semi-liquid and bitumen sand, the reliance on imported bitumen/asphalt for road construction and maintenance in Nigeria has reduced road coverage and quality. To use local bitumen as a binder in pavement construction, an efficient upgrading process is required using polymers, nanomaterials, and other chemical additives. However, the selection of an appropriate modifier depends on many factors including the origin, elemental and chemical composition of bitumen. This review presents vital properties of Nigerian bitumen extracted from oil wells and tar sands with the view to identifying potential additives as solutions for its upgrading. Based on predefined selection criteria, we conducted a systematic review of the literature. We gathered information on the current state of knowledge about the major issues encountered during the polymeric modification of bitumen. In addition, data on existing practices used by various road researchers to address such issues was gathered. Effort was made to review waste packaging polymers and plastics for possible utilization to ensure sustainable pavement infrastructure in Nigeria. The results of this review showed relatively little information on Nigerian bitumen upgrading. Many authors have investigated different polymer additives on asphaltic bitumen sourced from different countries and the results has pointed to the capability of polymeric modification to improve some of the properties of bitumen. A knowledge gap however, exists in the optimization of polymer dosage, and characterization of bitumen at the SARA level to aid the understanding of the effects of polymeric modification and mechanisms involved during the pavement degradation. Additionally, it has been challenging to generalize the effects of different polymers due to the variation of bitumen properties from different sources. This review identifies the potential for upgrading Nigerian bitumen using polymer additives, the potential of waste plastics, crumb rubbers, and packaging waste materials as alternative and sustainable additives also highlighted., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Prof. Salawudeen, Taofeeq Olalekan reports financial support was provided by Tertiary Education Trust Fund under 2020 grants batch 7. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

The paper has analyzed influence of additives representing a group of thermoplastic elastomers and complex thermoplast-based modifiers on fatigue life of asphalt concrete. Regularities in time have been determined in the paper and close values of their physical and mechanical properties have been obtained while using various types of binders and modifiers. Statistic and laboratory investigations have made it possible to obtain theoretical parameters of the fatigue life for materials used for road dressing. The analysis has been based on statistical values of ordinary and modified asphalt concrete and asphalt concrete mixes of C- and A-type obtained during the experiments for the period from 2010 till 2016. A statistic analysis has permitted to compare a parameter Ипл (resistance index to plastic deformations) with such parameters as ny (number of elastic constraints) and Rc (threshold structural strength). 12 calculations (Nos. 1–12) have been carried out in order to realize targets of the second investigation. Calculative characteristics of asphalt concrete required for determination of reliability parameters have been estimated in the paper. A bottom layer of twoor three-coat pavement has been selected as an object of the investigation due to the fact that it is more often subjected to an impact of cyclic tensile stresses caused by a transport load. The required value for calculation of tensile stresses s at calculated temperature 0 has been accepted on the basis of executed estimations while using finite elements method and distribution of stresses has been determined along structure with 20 cm thickness due to load А2. Corresponding conclusions have been made in accordance with the obtained results.

Passivation of organometal halide perovskites with polar molecules has been recently demonstrated to improve the photovoltaic device efficiency and stability. However, the mechanism is still elusive. Here, it is found that both polymers with large and small dipole moment of 3.7 D and 0.6 D have negligible defect passivation effect on the MAPbI3 perovskite films as evidenced by photothermal deflection spectroscopy. The photovoltaic devices with and without the polymer additives also have comparable power conversion efficiencies around 19%. However, devices with the additives have noticeable improvement in stability under continuous light irradiation. It is found that although the initial mobile ion concentrations are comparable in both devices with and without the additives, the additives can strongly suppress the ion migration during the device operation. This contributes to the significantly enhanced electrical‐field stress tolerance of the perovskite solar cells (PVSCs). The PVSCs with polymer additives can operate up to −2 V reverse voltage bias which is much larger than the breakdown voltage of −0.5 V that has been commonly observed. This study provides insight into the role of additives in perovskites and the corresponding device degradation mechanism. [ABSTRACT FROM AUTHOR]

The organic–inorganic halide perovskite solar cells (PSCs) are rapidly developed in just a few years due to its high power conversion efficiency. However, it still faces some critical issues, one of which is the presence of toxic lead (Pb2+). Recent researches show that barium (Ba2+) can partially replace the Pb2+ in perovskite structure and achieve a promising device performance because of its adequate ionic radius. However, the optimal replacement amount of Ba2+ in perovskite is still limited. Herein, the methylammonium (MA)/formamidinium (FA) mixed‐cation perovskite is used as the active layer in PSCs and Pb2+ is partially substituted with Ba2+. Compared with the pure MA system, the best device efficiency can be achieved using higher Ba2+ replacement ratio. In addition, while introducing the appropriate polymer additive, the replacement ratio can be further increased without compromise of device efficiency. Using polyethylene glycol as polymer additive, 10.0 mol% Ba‐doped MA/FA mixed‐cation PSC with an efficiency of 16.1% can be realized. It is believed that this report provides an effective strategy to fabricate high‐performance lead‐reduced PSCs. [ABSTRACT FROM AUTHOR]

[Display omitted] • The addition of the polymer improved the hydrophobicity of the polyurethane surface. • PAM and PEO combine directly with hydrophobic surfaces and form a cover layer. • XG and GG form aggregates with water first and then transfer to hydrophobic surfaces. • PAM-polyurethane hydrophobic surface has a better synergistic effect than others. The drag reduction synergy of four types of high-molecular polymers, namely polyacrylamide, poly(ethylene oxide), xanthan gum, and guar gum, with polyurethane hydrophobic surfaces, was investigated by both experiments and molecular simulations. The synergistic mechanisms of polymers and hydrophobic surfaces were revealed using Monte Carlo and molecular dynamics simulations in terms of interfacial interactions between polymers and water molecules, intermolecular interactions, and the adsorption conformation of polymers on hydrophobic surfaces. The addition of the polymer improved the hydrophobicity of the polyurethane surface, with flexible polymers having a more substantial effect than rigid polymers, according to both simulations and contact angle experiments. Furthermore, based on the transient configuration of polymer and water molecules moving on the hydrophobic surface, the kinetic process is divided into three stages: water molecule aggregation, water molecule-induced deformation, and polymer extension on the hydrophobic surface. Meanwhile, PAM and PEO combine directly with hydrophobic surfaces and form a cover layer with water molecules, whereas XG and GG prefer to form aggregates with water molecules first and then transfer to hydrophobic surfaces. The PAM-polyurethane hydrophobic surface, in particular, has a better synergistic effect than others, and its synergistic mechanism is related to the larger radius of gyration, stronger interaction with water molecules, and higher stability of the drag reduction system. [ABSTRACT FROM AUTHOR]

Cracks in catalyst layers (CLs) are a potential source of long-term failure in a fuel cell membrane electrode assembly (MEA). While modifications to the CL ink formulation can affect the degree of cracking, these changes may lead to lower initial performance than their cracked analogues due to the established link between formulation and performance. In this work, we explored the use of polymeric additives to mitigate CL cracks. Small quantities of poly (acrylic acid), poly (ethylene oxide), poly (methyl methacrylate), or poly (vinyl alcohol) – 5 wt% relative to ionomer mass – were added to the ink prior to its final mixing. Poly (vinyl alcohol) resulted in crack–free CLs, whereas the other polymers resulted in CLs with similar crack percentages as the control CL. Through a combination of transmission electron microscopy, X-ray computed tomography, and infrared spectroscopy, we ascribed the crack–mitigating mechanism of poly (vinyl alcohol) to its ability to hydrogen–bond with Nafion, the ion conducting polymer binder in the catalyst ink. Initial performance of this non–cracked electrode exhibited nearly identical electrochemical behavior to its cracked counterpart, demonstrating that PVA additives successfully reduce cracks while maintaining cell initial performance. [Display omitted] • Ink formulation is modified by small quantities of polymer additives. • Poly (vinyl alcohol) (PVA) rendered crack-free rod-coated gas diffusion electrodes. • Catalyst networks are formed through ionomer-PVA H-bonding interactions. • PVA does not negatively impact electrochemical performance. [ABSTRACT FROM AUTHOR]

The pressure-viscosity coefficient, α, is a measure of the pressure dependence of the viscosity of the liquid in elastohydrodynamic lubrication (EHL). There seems to be confusion around the understanding of the pressure-viscosity response in the inlet zone. In this paper the values of α were obtained from measurements of viscosity as a function of pressure and offers a understanding on the piezoviscous effect at various inlet pressures for those liquids. Moreover, the viscosities of several commercial engine oils and laboratory blends of mineral and synthetic base oils with polymer additives were measured at pressures up to 1 GPa and at temperatures of 40°, 75°, and 100°C. It was observed in some of these materials The significant changes within viscosity are temperature- and pressure-dependent. Analysis of the experimental results indicated that the solidification (significant increase viscosity) is due to liquid-solid phase transitions occurring in the lubricant's polymer additives. Thus, this paper gives evidence on the role of molecular weight and concentration of polymer and its influence on the pressure and temperature-dependent onset of the phase transitions. This transition has not been discussed in the open literature and is not accounted for in current bearing design using the Barus equation or the modified Yasatomi equation and may be the cause of some bearing damage modes.

Vulcanization accelerators (VAs) serve as crucial additives in synthetic rubber on a global scale. Despite their widespread use, the environmental presence, distribution, and associated exposure risks of VAs remain poorly understood. This study compiled a target list and conducted a screening for eight classes encompassing 42 VAs in diverse urban dust samples from South China. A total of 40 of the 42 target VAs were detectable across all four studied regions, among which 30 were identified for the first time in the environment. Among the eight structure-classified VA classes, xanthates exhibited the highest concentrations (median: 3810-81,300 ng/g), followed by thiazoles, guanidines, sulfenamides, dithiocarbamates, thiurams, thioureas, and others. The median total concentrations of all target VAs (∑VAs) were determined to be 5060 ng/g in road dust, 5730 ng/g in parking lot dust, 29,200 ng/g in vehicle repair plant dust, and 84,300 ng/g in household dust, indicating the widespread presence of numerous rubber-derived VAs in various urban environments. This study marked the first systematic effort to identify a wide range of emerging rubber-derived VAs prevalent in urban environments. The findings call for increased attention to these widely utilized but less well-evaluated chemicals in future research and environmental management efforts.

A scheme for the production of plastic greases based on high-boiling fractions of oil sludge and used lubricating oils, as well as polymer waste, in the form of HDPE, LDPE, and PP, that is used as a thickener, has been proposed. Based on the used lubricating oils and polymer thickeners, grease lubricants were obtained. They can be used in the temperature range, on average, up to 80-130 °C (depending on the polymer) and speed mode in the bearing up to 4000 rpm. These greases are not worse in their properties to classical ones; analogs obtained based on distillate fractions, thickened with metal soaps, which are widely used in industry today. [ABSTRACT FROM AUTHOR]

Abstract Materials in direct contact with food should be monitored for the presence of species able to migrate into food. A direct method based on liquid extraction surface analysis nanoelectrospray mass spectrometry (LESA-nanoESI-MS) was developed for the analysis of the migrating species from a polymer film. Different types of molecules: post-polymerization residues, degradation products (oligomers resulting from polymer recycling, products of polymer oxidative degradation) and anti-oxidant additives (vitamin E) were demonstrated to be detected and identified, and determined quantitatively if relevant calibration standards are available. The method was validated by a comparison a standard method based on with bulk extraction mass spectrometry. It offers considerable advantages over the latter in terms of drastically reduced analysis time and solvent consumption. Also, LESA-nanoESI-MS produced simpler spectra (limited to compounds able to migrate into food) than Direct Analysis in Real Time (DART). Graphical abstract Image 1 Highlights • Method to evaluate the safety and functionalization of polymer food packings. • fast, eco-friendly and highly reproducible analysis with no sample preparation. • Possibility of quantitative monitoring of the quality of "intelligent" packings. [ABSTRACT FROM AUTHOR]

The aim of this study is to analyze the effect of natural additive incorporation on processing nanocomposites and their effect on the functional characteristics of nanocomposites such as water uptake characteristics, drug adsorption and dissolution behaviors. Chitosan and montmorillonite were processed with olive oil and glycerin natural additives. In order to compare the processing results, the structure and the morphology of the polymer nanocomposites were examined by using infrared spectra, X-ray diffractograms and electron microscope images. Processing with nontoxic and healthful olive oil as a hydrophobizing agent overcame the high water uptake properties of the polymer nanocomposites and eliminated the use of other expensive chemicals. The nanocomposites without additives adsorbed the highest amounts of methylene blue at equilibrium. In vitamin B12 dissolution studies, not only the additives but also the reinforcement affected the results. Obviously, it can be seen that both the natural additive types and the reinforcement modification effects governed the drug adsorption and dissolution behaviors of the new tailored polymer nanocomposites. Moreover, the additives also improved the processing and handling abilities of these polymer nanocomposites. According to the results, these nanocomposites are promising candidates for medical applications like as a carrier for drug delivery and for skin treatment studies. [ABSTRACT FROM AUTHOR]

• High salinity gradients effect in ion-selective surface. • Non-linear electroconvection flow coupling with buoyancy force and polymer additives. • Energy analysis at ion selective interfaces. • Notable modulation of mass transfer capability. • Elastic energy accumulation in the extended space charge region. In advanced electrochemical systems, salinity gradients are widespread and profoundly affect the energy distribution and stabilities of the system. In our research, we thoroughly investigated the ion-selective surface electroconvection flow coupling with buoyancy effects and polymer additives. The variation in mass transfer properties and energy budgets are also investigated in detail. Our results show that polymer additives act as a destabilising factor in an unstable configuration when Rayleigh number Ra ≤ 1000. When Ra > 1000, polymer additives play a stabilizing role. For ion transport, viscoelasticity decreases the overlimiting current by up to 41% for no buoyancy effects. However, the overlimiting current drops by only 27% at large Ra number. Finally, details of the energy budgets reveal a marked salinity and elasticity dependency. The polymer additives can act as either kinetic energy (KE) sinks or KE sources. For small Weissenberg number Wi , polymer as KE sinks leading to ion transport reduction. For large Wi , the role of polymer changes to EK sources. The nonlinear ion transport can be attributed to role change of polymer in energy analysis. These mechanisms provide greater insight into the role of polymer in prevent premature cell failure and stabilizing electrodeposition. [ABSTRACT FROM AUTHOR]

[Display omitted] • The optimal micro-explosion was achieved in a stable emulsion for the first time. • A new way to regulate the intensity of micro-explosion. • The micro-explosion may be a coupling mechanism of thermodynamics and dynamics. • A new direction for spray units commonly used in chemical production. The emulsified feedstock technique is to improve the performance of products by using the micro-explosion phenomenon of emulsion. However, an obstacle to some applications of this technology is the contradiction between emulsion stability and micro-explosion intensity. For the first time, adding water-soluble polymers was proposed to solve this problem. Two polymers of xanthan gum (XG) and nonionic polyacrylamide (NPAM) were investigated and the results show that micro-explosions have five forms. As one of these five forms, the intensity of optimal micro-explosion is three orders of magnitude higher than other forms, and adding 0.5 g/dL XG increases the probability of optimal micro-explosion from 0 to 60% due to the low surface activity, strong thickening and pseudoplasticity of XG solutions. By contrast, NPAM does not promote micro-explosion because of its strong surface activity. Finally, a new mechanism for micro-explosions related to liquid–gas interfacial tension, liquid–liquid interfacial tension and viscosity is proposed. [ABSTRACT FROM AUTHOR]

Hindered amine light stabilizers (HALSs) represent a crucial class of polymer additives that are extensively used in plastics and other polymeric materials. However, their environmental presence and related exposure risks have until now remained unexplored. This study addressed this critical knowledge by examining dust and air particles collected in South China, utilizing a comprehensive analytical approach to identify and quantify nine monomeric HALSs. A total of seven of the nine studied HALSs were detected in the samples, with bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate (Tinuvin 770) and methyl 1,2,2,6,6-pentamethyl-4-piperidyl sebacate (HS-508) identified as the most abundant and widespread pollutants. Median total concentrations of HALSs ranged from 417 to 8,830 ng/g in urban dust samples and from 28.6 to 70.9 pg/m 3 in urban air particles. Notably, dust concentrations of HALSs significantly exceeded those of traditional well-known light stabilizers such as UV absorbers. Human exposure assessment indicated that in contrast to air inhalation dust ingestion represented a more substantial exposure pathway owing to the relatively low volatility of these newly identified chemicals. Predictive modeling suggests that many of the examined HALSs exhibited characteristics of persistence, high toxicity, or strong potential for long-range transport, underscoring their hazardous nature. This study represents the first comprehensive investigation into the prevalence of HALSs as a class of emerging pollutants widespread in the environment, necessitating heightened attention and further research in the future.

On the basis of the V. K. Stokes micro-continuum theory, the effects of couple stresses on the nonlinear dynamic response of the unbalanced Jeffcott’s flexible rotor supported by layered hydrodynamic journal bearings is presented in this paper. A nonlinear transient modified Reynolds’ equation is derived and discretized by the finite element method to obtain the fluid-film pressure field as well as the film thickness by means of the implicit Euler method. The nonlinear orbits of the rotor center are determined by solving the nonlinear differential equations of motion with the explicit Euler’s scheme taking into account the flexibility of rotor. According to the obtained results, the combined effects of couple stresses due to the presence of polymer additives in lubricant and the pressure dependent viscosity on the nonlinear dynamic response of the rotor-bearing system are significant and cannot be ignored or overlooked. As expected, these effects are more noticeable for polymers characterized by higher length molecular chains.

In this study, magnetic zeolitic imazolate framework-8 (Fe 3 O 4 @ZIF-8) was successfully synthesized by a typical hydrothermal method. The facile magnetic solid-phase extraction (MSPE) based on Fe 3 O 4 @ZIF-8 was proposed for concentrating polymer additives (antioxidants and ultraviolet absorbers). The conditions of MSPE process were optimized. An analytical method of magnetic solid-phase extraction followed by high performance liquid chromatography (MSPE-HPLC) was successfully established for the simultaneous determination of seven polymer additives in drinks and foods packed with plastic. The established method showed good precision, reproducibility, stability, and accuracy with the low limits of detection (0.03–0.15 ng/mL) and limits of quantification (0.08–0.50 ng/mL). The results of this study indicated the Fe 3 O 4 @ZIF-8 coupled with HPLC provided an efficient enrichment and determination method for polymer additives in drinks and foods. [ABSTRACT FROM AUTHOR]

Inclusion of minute concentrations of elongated long chain polymers is known to exhibit drastic reduction in frictional losses for turbulent fluid flows. The polymer chains interact with solvent molecules to act as eddy stress absorbers causing reduction in drag and inducing the viscoelastic nature in the fluid layer. In this work, we propose a characterization method for viscoelastic behavior of polymer-water solutions using a spray atomization experiment. The methodology is demonstrated for polyacrylamide and polyethylene oxide-based aqueous solutions. The experimental technique assesses the nature of the fluid using a predefined parameter, impact ratio (R). Computational fluid dynamics simulations of spray atomization are performed to validate the experimental values of the impact ratio. The simulation results indicate coherence with the experimental data, and are concordant with the reported behavior of such solutions in the literature. [ABSTRACT FROM AUTHOR]

Abstract: The role of a tertiary polymer‐based additive is investigated in increasing the efficiency of inverted low bandgap polymer:fullerene bulk heterojunction (BHJ) solar cells. Charge separation in polymer BHJ solar cells relies on the phase separation between electron accepting fullerene derivatives and photoactive polymers. Proper distribution of individual phases of suitable crystallinities within the active layer is a key factor for efficient charge transport/extraction and high photovoltaic performance. Here, it is demonstrated that the minor addition of a tertiary amorphous polymer, polystyrene (PS), with optimized molecular weights can increase the overall photovoltaic efficiency of poly[N‐9′‐heptadecanyl‐2,7‐carbazole‐alt‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole)]:phenyl‐C61butyric acid methyl ester (PCDTBT:PCBM) inverted BHJ solar cells, through the interfacial‐tension‐driven increase in crystallinities of photoactive phases and redistribution of PCBM molecules away from the top hole‐collecting anode interface. Complementary studies correlating polymer interfacial tension, blend internal structure, charge transport, and photovoltaic characteristics show that tertiary, high molecular‐weight polymers can serve as effective additives for improving the performance of low bandgap polymer solar cells. [ABSTRACT FROM AUTHOR]

Abstract: The laccase‐catalyzed oxidative polymerization of monomeric and dimeric lignin model compounds was carried out with oxygen as the oxidant in aqueous medium. The oligomers were characterized by using gel permeation chromatography (GPC) and matrix‐assisted laser desorption ionization time‐of‐flight mass spectroscopy (MALDI‐TOF MS) analysis. Oxidative polymerization led to the formation of oligomeric species with a number‐average molecular weight (Mn) that ranged from 700 to 2300 Da with a low polydispersity index. Spectroscopic analysis provided insight into the possible modes of linkages present in the oligomers, and the oligomerization is likely to proceed through the formation of C−C linkages between phenolic aromatic rings. The oligomers were found to show good UV light absorption characteristics with high molar extinction coefficient (5000–38 000  m−1 cm−1) in the UV spectral region. The oligomers were blended independently with polyvinyl chloride (PVC) by using solution blending to evaluate the compatibility and UV protection ability of the oligomers. The UV/Vis transmittance spectra of the oligomer‐embedded PVC films indicated that these lignin‐like oligomers possessed a notable ability to block UV light. In particular, oligomers obtained from vanillyl alcohol and the dimeric lignin model were found to show good photostability in accelerated UV weathering experiments. The UV‐blocking characteristics and photostability were finally compared with the commercial low‐molecular‐weight UV stabilizer 2,4‐dihydroxybenzophenone. [ABSTRACT FROM AUTHOR]

A versatile and robust process was developed for the fabrication of ceramic films in solid oxide fuel cells (SOFCs), allowing the microstructures of the films to be tailored from porous to dense. This nanoscale spray process was assisted by electrospray ionization and specific polymer additives such as polyvinyl pyrrolidone and polyvinyl butyral, and it provided a large degree of freedom for controlling the membrane microstructures of the cathode and electrolyte. The final spray-deposition-based SOFC cell, which consisted of a dense, thin electrolyte (thickness: ~4 µm) and a crack-free porous cathode layer (thickness: ~10 µm), exhibited notable reliability, an open-circuit voltage of ~1.11 V (approaching the theoretical value), and a maximum power density of ~805 mW/cm 2 at 650 °C, which is substantially higher than the power-generating performances of previously reported spray-deposition-based SOFCs. [ABSTRACT FROM AUTHOR]

Within this work, a fluorescence microscopy approach for the investigation of the distribution of polymer additives in polypropylene is presented. The fluorescent whitening agent 2,5-bis-(5-tert-butyl-benzoxazol-2-yl)-thiophene was used as a model compound representing other groups of polymer additives. So far, methods reported in the literature such as UV and IR microscopy offer a high spatial resolution, however, suffer from poor sensitivities, thus not allowing them to analyze samples with low additive concentrations typically used in engineering materials. Using the fluorescence microscopy technique, it was shown that independent from the applied concentrations (0.1–1.7 wt%), additives are distributed on a spherulitic scale with the majority being found at the spherulite boundary and only traces in the center. Furthermore, it could be demonstrated that the additive distribution is affected not only by the spherulite sizes but also by the cooling rate of the polymer melt leading to more or less pronounced additive distribution patterns. [ABSTRACT FROM AUTHOR]