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We analyze the displacements of the particles of a glass-forming molecular liquid perpendicular to a confining solid surface using extensive molecular dynamics simulations with atomistic models. In the vicinity of an attractive surface, the liquid molecules are trapped. Transient localization of liquid molecules near the surface introduces a relaxation process related to the escape of molecules from the surface into the dynamics of the interfacial liquid layer. To describe this process, we analyze several dynamical observables of the confined liquid. The self-intermediate scattering function and the mean-squared displacement of the particles located in the interfacial layer are dominated by the process of escaping from the surface. This relaxation process is also associated with a strong heterogeneity in the mobility of the interfacial particles. The studied model liquid is hydrogenated methyl methacrylate. For the confining wall, we consider different models, namely a periodic single layer of graphene and a frozen amorphous configuration of the bulk liquid (frozen wall). Near graphene, where the liquid molecules form a layered structure and adopt parallel-to-surface orientation, a clear separation between small-scale movements of the molecules near the surface and the process of escaping from the surface is observed. This is reflected in the three-step relaxation of the interfacial layer. However, near the frozen wall, where the liquid molecules do not have a preferential alignment, a clear three-step relaxation is not seen, even though the dynamical quantities are controlled by the process of escaping from the surface. [ABSTRACT FROM AUTHOR]

Diffusion-controlled deactivation of excited phenanthrene and oxidation of triplet aryl-nitrene by molecular oxygen were used to determine the energetics of oxygen jump rates in the set of glassy polymers: poly(methyl methacrylate), poly(n-butyl methacrylate), polycarbonate, polystyrene, and polysulfone. To interpret experimental results, a simple model based on the transition state theory of diffusion jump has been used. The kinetic Monte Carlo simulations of phenanthrene deactivation and nitrene oxidation were carried out in a cubic lattice that modeled a polymer matrix. The bonds of the lattice were assigned to be activation barriers for the diffusion jumps of oxygen molecules from one site of the lattice to another. The standard deviation, σ‡, and spatial correlation length, rc, of the free energy of diffusion jump have been determined. It is shown that the spatial correlation of oxygen jump rates on a nanometer scale and the entropic nature of the dynamic heterogeneity are common features of all the studied polymers. [ABSTRACT FROM AUTHOR]

The reversible bonding of microfluidic chips has been developing rapidly with the requirement of reusable microfluidic devices or the need to obtain the samples inside the chip. Traditional bonding methods for polymer-based microfluidics, e.g., thermal bonding, permanently attach the substrate and cover plate. Sometimes, once the chip flow channel is blocked, it is difficult to clean and affect the reusability of the chip. This study proposes a new reversible bonding method for poly (methyl methacrylate) (PMMA) microfluidic chips with the help of stretch release adhesive strips. The designed microchannels were fabricated on the surface of PMMA plates using C[O.sub.2] laser irradiation. Then, stretch release adhesive strips were used as an intermediate layer between the substrate (with microchannels) and another flat PMMA/PS/PC plate to seal the microchannel. The assembled chip sets were bonded at room temperature with bonding strength comparable with other permanent bonding methods. Experimental results show that simply pulling the adhesive layer by applying a shear force can easily detach the intermediate adhesive layer from both the substrate and cover plate to separate the bonded chipset. The proposed reversible bonding method is simple, rapid and has low residue and high bonding strength. Bacterial culture experiments were also conducted to verity the biocompatibility of the proposed bonding method. The proposed reversible bonding technique can be used for polymer-based microfluidic devices that require sample recovery or chip reuse. Highlights * The stretch release adhesive strip can provide high bond strength. * It allows easy peeling for reversible bonding. * It bonds at room temperature with simple operation. * It has good transparency for easy observation of experiments. * It has good biocompatibility. KEYWORDS microfluidics, reversible bonding, stretch release adhesive strip, 1 | INTRODUCTION Microfluidic technology is a technique that utilizes fluids at the micro- or nanometer scale for precise operations and control, with widespread applications in biology, chemistry, medicine, and [...]

The work demonstrates, for the first time, thermo-responsive, water-insoluble, hydrogel-based, nano-fibrous filter media comprised of copolymers of N-isopropylacrylamide (NIPAM) and methyl methacrylate formed by electrospinning. Moreover, a comprehensive novel physical explanation of all aspects responsible for the physical mechanisms resulting in the thermo-responsive regulation of the water flow rate and an enhanced interception of nanoparticles by such filter membranes is given. They are the wettable-non-wettable transition, pore, and fiber-size changes, as well as a diminishing filter thickness at the lower critical solution temperature (LCST) of the copolymers developed here, which interplay with a significant reduction in the water viscosity with temperature. Poly(N-isopropylacrylamide) (PNIPAM) hydrogel is an attractive material because of its thermo-responsive properties. Its wettability changes with water temperature. This characteristic holds great promise for the development of advanced filter media and related responsive materials. In this study, PNIPAM hydrogels were designed and transformed into filter membranes for applications in water filtration in biomedical and other related systems. These thermo-responsive filter membranes offer the potential for enhanced filtration efficiency, selectivity, and the overall system performance. Here, two different procedures were adopted to form water-insoluble thermo-responsive filter media based on PNIPAM hydrogels. The PNIPAM-based hydrogels were electrospun, resulting in the formation of thermo-responsive water-insoluble nanofiber membranes. These membranes underwent a series of comprehensive experiments to assess their performance and characteristics, including mass loss, water droplets for the wettability assessment, filtration tests, shrinkage measurements, and microscopic observations. These diverse experiments yield a full understanding of the PNIPAM-based nanofiber membranes' properties and their potential applications. [ABSTRACT FROM AUTHOR]

Polybutadiene grafted methyl methacrylate copolymer (PBL‐g‐MMA, MB) with core‐shell structure was prepared by emulsion polymerization. Without adding compatibilizers, PC/ABS composites were blended with polycarbonate (PC) and SAN. The effects of methacrylate butadiene (MB) on mechanical properties, flow properties, and thermal properties of PC/ABS composites were investigated. The results show that the addition of MB has obvious toughening effect on PC/ABS, effectively improving the mechanical properties and melt flow rate (MFR) of PC/ABS composites, and hence significantly improving the processability of PC/ABS composites. When the amount of MB is 12 phr, the notched impact strength of PC/ABS blend can reach up to 430 J/m. This is several times more than pure PC resin. The scanning electron microscope (SEM) analysis results show that the compatibility of PC/ABS and the impact strength of PC/ABS blend are improved with the increase of MB dosage. With the increase of MB content, the softening temperature of Vicat first decreased and then increased. It increased with the increase of PC content. [ABSTRACT FROM AUTHOR]

Polylactic acid/poly(methyl methacrylate) (PLA/PMMA) composite fibers with high performance were fabricated using melt spinning technique. The crystallization, lamellae orientation and physical properties of composite fibers were investigated systematically. The addition of PMMA (0–20 wt%) has improved the hydrolysis resistance of composite fibers by preventing water molecules from penetrating and diffusing through the fibers, but the strength and heat resistance were reduced at the same time. The stereocomplex crystallites (SC) formed before spinning by introducing poly(D‐lactide) (PDLA) (3 wt%) in poly(L‐lactide) (PLLA) matrix and acted as nucleating agents to enhanced the crystallization and lamellae orientation of PLLA matrix, which improved the physical properties of PLA composite fibers resultful. The tensile strength of PLA fibers with 3 wt% PDLA and 5 wt% PMMA was increased 31% as well as the boiling water shrinkage and the hydrolysis rate were decreased 30% and 33% in relation to PLLA fibers. Finally, the hydrolysis resistance was further enhanced on the basis of realizing high strength and heat resistance, which is of great significance for preparing durable PLA fiber materials and expanding their application. [ABSTRACT FROM AUTHOR]

In the present work, the incorporation of hydrophobic porphyrins in organic polymers through electrochemically induced polymerization of monomers on conventional electrodes and the preliminary investigations on the electrocatalytic activity of these modified electrodes are explained. Electropolymerized porphyrins show better activity than organic polymers of N‐isopropylacrylamide, triethylene glycol methyl ether methacrylate, and glycerol 1,3‐diglycerolate diacrylate for nitrite oxidation due to the presence of cobalt metal ion. Among the porphyrins investigated, electropolymerized cobalt tetra‐2‐thienylporphyrin requires the least overpotential, due to ease of polymerization and better coating on glassy carbon electrode compared with that of cobalt tetraphenylporphyrin and cobalt tetra‐3‐thienylporphyrin. On encapsulating these porphyrins in organic polymers, improved current and lower overpotential are noticed. [ABSTRACT FROM AUTHOR]

Fullerene has been acknowledged as a significant nanocarbon nanofiller enhancing the imperative polymer characteristics. Since, thermoplastic polymers constitute a large group of polymeric materials, fullerene has been used as reinforcement in these matrices mostly via non-covalent means. This state-of-the-art review article summarizes thermoplastic polymer nanocomposites reinforced with fullerene nano-additives without involving any covalent interactions. Accordingly, thermoplastic polymer/fullerene nanocomposites of interest have non-covalent or physical interactions in the matrix-nanofiller such as van der Waals forces, electrostatic interactions, hydrogen bonding, and aromatic stacking interactions. Number of thermoplastic polymers including polyamide, polyurethanes, and block copolymers have been non-covalently or physically reinforced with the fullerene molecules. Ensuing high performance thermoplastic polymer/fullerene nanocomposites exhibited improved microstructure, electrical, mechanical, thermal, and other physical properties. Enhancements in the thermal, mechanical, and electrical properties of the thermoplastic/fullerene nanomaterials were found dependent upon the nanofiller contents, orientations, interfacial effects, and processing. Consequently, the polyamide/fullerene systems were found efficient to enhance the glass transition up to 260°C, in addition to optimum mechanical properties. Polyurethane/fullerene systems performed better for improved tensile strength and young's modulus features up to 90 MPa and 48 GPa, respectively. System based on poly (methyl methacrylate) and fullerene has resulted in high thermal degradation temperature in the range of 501-633°C with fine electrical conductivity of 1.3 Scm−1. Using combination of fullerene and graphene nanofiller (due to synergistic effects) has been found to improve the electrical conductivity considerably in the range of 1.8–2.5 Scm−1 for a polystyrene and block copolymer system. However, attaining fine fullerene nanoparticle dispersion of non-covalently reinforced matrices have been found important affecting the final nanocomposite properties. Consequently, processability and essential characteristics of non-covalently fullerene filled nanocomposites can be influenced due to nanoparticle aggregation. Hence, the physical property enhancement potential of physical linking between the non-covalently linked thermoplastics-fullerene has been portrayed in this article. Research on non-covalently interacted thermoplastic polymer/fullerene nanocomposites revealed technical potential ranging from energy/electronic devices to engineering and biomedical sectors. This review article can be a useful guide for the field researchers towards the development of advanced systems using non-covalently linked polymer/fullerene nanomaterials for future technical applications. [ABSTRACT FROM AUTHOR]

Functional triblock copolymers (BCPs), i.e., poly(glycidyl methacrylate/methyl methacrylate)-b-poly(lauryl methacrylate)-b-poly(glycidyl methacrylate/methyl methacrylate) triblock copolymers [(P(GMA/MMA)-b-PLMA-b-P(GMA/MMA)], were investigated as toughening modifiers for all-methacrylate polymer blends. Methyl methacrylate (MMA) was copolymerized with methacrylic acid (MAA) in the presence of the BCPs. Without MAA in the polymethacrylate matrices, the BCP blends formed micron-scale phase structures by polymerization-induced phase separation. In matrices copolymerized with MAA, self-assembled nanostructures, such as curved lamellae, worm-like cylindrical micelles, or spherical micelles were formed. The BCP blends with worm-like cylindrical nano-micelles achieved much higher fracture toughness than those with spherical nano-micelles. The toughening mechanisms were elucidated by transmission electron microscopy. Cavitation was initiated in worm-like cylindrical nano-micelles, and the aligned cavitation formed craze-like deformation with increased loads. This relieves hydrostatic tensile stress in front of the crack tip, forming a large shear yield zone within the craze-like deformation region, contributing to high toughness. [ABSTRACT FROM AUTHOR]

This work demonstrates a novel polymerization‐derived polymer electrolyte consisting of methyl methacrylate, lithium bis(trifluoromethanesulfonyl)imide and fluoroethylene carbonate. The polymerization of MMA was initiated by the amino compounds following an anionic catalytic mechanism. LiTFSI plays both roles including the initiator and Li ion source in the polymer electrolyte. Normally, lithium bis(trifluoromethanesulfonyl)imide has difficulty in initiating the polymerization reaction of methyl methacrylate monomer, a very high concentration of lithium bis(trifluoromethanesulfonyl)imide is needed for initiating the polymerization. However, the fluoroethylene carbonate additive can work as a supporter to facilitate the degree of dissociation of lithium bis(trifluoromethanesulfonyl)imide and increase its initiator capacity due to the high dielectric constant. The as‐prepared poly‐methyl methacrylate‐based polymer electrolyte has a high ionic conductivity (1.19 × 10−3 S cm−1), a wide electrochemical stability window (5 V vs Li+/Li), and a high Li ion transference number (tLi+) of 0.74 at room temperature (RT). Moreover, this polymerization‐derived polymer electrolyte can effectively work as an artificial protective layer on Li metal anode, which enabled the Li symmetric cell to achieve a long‐term cycling performance at 0.2 mAh cm−2 for 2800 h. The LiFePO4 battery with polymerization‐derived polymer electrolyte‐modified Li metal anode shows a capacity retention of 91.17% after 800 cycles at 0.5 C. This work provides a facile and accessible approach to manufacturing poly‐methyl methacrylate‐based polymerization‐derived polymer electrolyte and shows great potential as an interphase in Li metal batteries. [ABSTRACT FROM AUTHOR]

Potential applications of colloidal polymer nanoparticles in the preparation of smart inks are investigated by physical incorporation of the oxazolidine molecules. Precise adjusting the polymer chain flexibility and polarity is achieved by controlling the ratio of methyl methacrylate and butyl acrylate monomers in the polymerization reaction. In addition, nanofibrous indicators of acid–base vapors are prepared from the latex nanoparticles. This can be beneficial for creating materials that sense and respond to environmental changes, such as humidity or moisture and acidity. Thermochromic inks are prepared by microencapsulating crystal violet lactone dye (CVL) in polymer matrices to prevent their release into the aqueous media. Combining two distinct systems with varying triggers, such as light and temperature, provides an effective strategy for double‐encryption anticounterfeiting and crack and scratch detection and indication applications. Preparing labels impregnated with double‐responsive inks, a novel approach is developed for food spoilage detection and preservation indication. Labels are manufactured using polymer nanoparticles, which contain photoluminescent oxazolidine molecules, as well as a trinary mixture of CVL within core–shell latex particles as the thermochromic dye. The combination of these two responsive elements transforms traditional packaging into a dynamic and interactive sentinel for the food it holds. [ABSTRACT FROM AUTHOR]

We describe a methodology of post‐polymerization functionalization to enable subsequent bulk depolymerization to monomer by utilizing mechanochemical macro‐radical generation. By harnessing ultrasonic chain‐scission in the presence of N‐hydroxyphthalimide methacrylate (PhthMA), we successfully chain‐end functionalize polymers to promote subsequent depolymerization in bulk, achieving up to 82 % depolymerization of poly(methyl methacrylate) (PMMA) and poly(α‐methylstyrene) (PAMS) within 30 min. This method of depolymerization yields a high‐purity monomer that can be repolymerized. Moreover, as compared to the most common methods of depolymerization, this work is most efficient with ultra‐high molecular weight (UHMW) polymers, establishing a method with the potential to address highly persistent, non‐degradable all‐carbon backbone plastic materials. Lastly, we demonstrate the expansion of this depolymerization method to commercial cell cast PMMA, achieving high degrees of depolymerization from post‐consumer waste. This work is the first demonstration of applying PhthMA‐promoted depolymerization strategies in homopolymer PMMA and PAMS prepared by conventional polymerization methods. [ABSTRACT FROM AUTHOR]

Quasi‐solid‐state thermocells (QTECs) show promise as a power source for wearable devices by converting body heat into electricity. While significant progress has been made with p‐type elements for QTECs, challenges remain with their n‐type counterparts. Here, a high‐performance n‐type QTEC element is presented, using a copolymer hydrogel that outperforms conventional p‐type elements. This copolymer hydrogel combines hydrophilic zwitterionic sulfobetaine methacrylate (SBMA) for ionic conduction and hydrophobic methyl methacrylate (MMA) for structural stability. By increasing the MMA content from 35 to 100 wt.%, versatile control is achieved over the hydrogel's elastic modulus (72 kPa to 127.7 MPa) and tensile strength (54 kPa to 6.7 MPa). A high mechanical toughness of 7.2 MJ m−3 is also achieved at 68 wt.% MMA. The mechanically robust and high toughness p(SBMA‐MMA) hydrogel is then immersed in Fe(ClO4)2/3 solutions of different concentrations to evaluate its performance as an n‐type QTEC element. The hydrogel with 0.8 M Fe(ClO4)2/3 exhibits a high ionic Seebeck coefficient of −1.7 mV K−1, a power density of 1.1 mW m−2 K−2, and an elastic modulus of 1.6 MPa, which is similar to that of human skin. Finally, the optimized n‐type p(SBMA‐MMA) hydrogels demonstrate the potential application for wearable devices. [ABSTRACT FROM AUTHOR]

Achieving amorphous polymers with ultralong room‐temperature phosphorescence (RTP), tunable organic afterglow, and reversible photoactivation behavior is highly desirable for practical applications but challenging. Herein, simple positional isomers with three carboxyl groups located in the ortho, meta, and para positions of the triphenylamine skeleton are designed and synthesized. By physically blending with the poly(vinyl alcohol) matrix, these isomers show ultralong RTP properties, among which the meta‐isomer has the longest RTP lifetime (620.1 ms). Theoretical calculations reveal that the more efficient intersystem crossing, the slower radiative decay rate of the lowest triplet excitons, and stronger intermolecular hydrogen‐bonding interactions should be responsible for the superior RTP property of meta‐isomer. Furthermore, the tunable organic afterglow is readily realized via a triplet‐to‐singlet energy transfer process. More impressively, the meta and para isomers exhibit reversible photoactivated ultralong RTP properties after embedding into the rigid poly(methyl methacrylate) matrix. Finally, amorphous and flexible polymer films prepared from these positional isomers show potential applications in advanced anti‐counterfeiting and multilevel encryption through subtly combining ultralong RTP lifetime, tunable organic afterglow, and reversible photoactivation behavior. [ABSTRACT FROM AUTHOR]

Super absorbent polymer based on methyl methacrylate (MMA), methacrylic acid (MAA) has been prepared during the present work for coating the top layer of feminine sanitary napkins. Synthesized polymers were coated on the needly punched cotton and adjusted as the top layer of the sanitary napkins, which has been prepared. The samples were evaluated by means of absorbency capacity, rewet back, strike through, and pH by the comparative study with commercially available sanitary napkin. The most suitable ratio of monomers (60 g MMA, and 40 g MAA) for synthesizing polymer was suggested. Absorbency capacity of the said ratio is competing with commercial sample with 63.68 g absorbent capacity. Specially, pH of prepared polymers suggested the acidic value and those are more preferable for maintaining the acidic pH of vagina at the menstrual time. Present work suggests the polymer, which can be utilize for coating the feminine napkin by the comparative result suggested by absorbency capacity, rewet back, strike through, and pH. [ABSTRACT FROM AUTHOR]

Doping in semiconductor quantum dots (QDs) using optically active dopants tailors their optical, electronic, and magnetic properties beyond what is achieved by controlling size, shape, and composition. Herein, we synergistically modulated the optical properties of eco‐friendly ZnInSe2/ZnSe core/shell QDs by incorporating Cu‐doping and Mn‐alloying into their core and shell to investigate their use in anti‐counterfeiting and information encryption. The engineered "Cu:ZnInSe2/Mn:ZnSe" core/shell QDs exhibit an intense bright orange photoluminescence (PL) emission centered at 606 nm, with better color purity than the undoped and individually doped core/shell QDs. The average PL lifetime is significantly extended to 201 ns, making it relevant for complex encryption and anti‐counterfeiting. PL studies reveal that in Cu:ZnInSe2/Mn:ZnSe, the photophysical emission arises from the Cu state via radiative transition from the Mn 4T1 state. Integration of Cu:ZnInSe2/Mn:ZnSe core/shell QDs into poly(methyl methacrylate) (PMMA) serves as versatile smart concealed luminescent inks for both writing and printing patterns. The features of these printed patterns using Cu:ZnInSe2/Mn:ZnSe core/shell QDs persisted after 10 weeks of water‐soaking and retained 70 % of PL emission intensity at 170 °C, demonstrating excellent thermal stability. This work provides an efficient approach to enhance both the emission and the stability of eco‐friendly QDs via dopant engineering for fluorescence anti‐counterfeiting applications. [ABSTRACT FROM AUTHOR]

The urgent need to mitigate climate change has spurred research into innovative carbon dioxide (CO2) capture materials. In this study, the design and synthesis of CO2‐responsive diblock copolymers, poly (N‐[3‐(dimethylamino)propyl]‐acrylamide)‐b‐poly(methyl methacrylate) (PDMAPAm‐b‐PMMA) are focused on via a two‐step reversible addition−fragmentation chain‐transfer (RAFT) polymerization as well as the application of the synthesized diblock copolymer as a membrane for CO2 capture. The resulting diblock copolymer possesses distinct blocks with varying properties. The poly (N‐[3‐(dimethylamino)propyl]‐acrylamide) (PDMAPAm) block provides CO2‐responsive behavior, while the poly(methyl methacrylate) (PMMA) block contributes to mechanical stability. The gas transport properties of the fabricated thin‐film composite membrane made of PDMAPAm‐b‐PMMA are measured. It is determined that the copolymer exhibits dual responsiveness towards CO2 and can be tailored for use in fabrication of membranes for direct air capture (DAC). [ABSTRACT FROM AUTHOR]

With the increasing of bone diseases, bone substitute biomaterials have been urgently needed and recognized as effective therapeutic strategies for bone regeneration. However, the improper mechanical properties, uncontrolled curing time, and exothermic heat limited their clinical applications. Herein, a facile prepared injectable bone cement consisting of poly(methyl methacrylate), hydroxyapatite, curcumin, oxidized sodium alginate, and polyethylenimine is constructed. By taking advantage of the acid‐ and H2O2‐responsive covalent bonds, the resultant bone cement not only possessed superior compressive strength (>70 MPa), bending strength (>50 MPa), suitable curing time (9–14 min), and low exothermic heat (<42 oC), but also can release the drugs under the trigger of osteomyelitis microenvironment. Both at the cellular level and rat osteomyelitis models, the prepared bone cement exhibited excellent biocompatibility (cell survival rate: >97%; hemolysis ratio: <1.8%), anti‐bacterial (the lowest bacterial survival rate: ≈1.7%), anti‐inflammatory (the expressions of iNOS, CD86, TNF‐α, IL‐1β, and IL‐6 are significantly inhibited) and the ability to promote bone regeneration (proliferation of osteoblasts and inhibition of osteoclasts). It is believed that this work will provide a bioactive organic/inorganic composite material for bone tissue engineering, the distinctive human‐friendly low exothermic heat, and advantages of prodrug technique incorporated multi‐function integration endow them potential clinical application prospects. [ABSTRACT FROM AUTHOR]

Calcium sulfate whiskers (CSW) exhibit significant surface polarity and high surface energy, leading to aggregation when directly incorporated into polymer matrices, significantly affecting the mechanical properties of the composites. Sodium oleate (SO) was used to modify CSW, introducing –C=C– active groups on the surface, followed by in‐situ graft polymerization of sodium oleate‐modified CSW (SO‐CSW) with methyl methacrylate (MMA) to prepare CSW‐g‐PMMA composites. The modification mechanism of SO and PMMA on CSW, as well as the surface modification effects on CSW, were studied using DRIFT, XRD, XPS and TEM. The results show that oleic acid ions adsorb onto the surface of CSW in two forms. One is chemisorption, in which the oleic acid ions are adsorbed on the calcium ions site on the surface of CSW in a bridging way. The other is physical adsorption, oleic acid ions and dissolved calcium ions in the form of precipitation adsorbed on the outermost layer of CSW. After in‐situ polymerization, PMMA was successfully grafted onto the surface of CSW, and the thickness of the surface PMMA coating layer was approximately 67 nm. CSW‐g‐PMMA was used as a filler in the melt blending with polypropylene (PP) to prepare PP composites. CSW‐g‐PMMA mainly toughens and enhances the mechanical properties of PP composites in the form of crack bridging, crack deflection and pull‐out effect. Highlights: The mechanism of sodium oleate modified calcium sulfate whisker (CSW) has been investigated. One is chemical adsorption that the oleic acid ions are adsorbed on the calcium ions site on the CSW surface in a bridge way. The other is physical adsorption that oleic acid ions and dissolved calcium ions are adsorbed in the form of precipitation on the outer layer of CSW.After the modification of sodium oleate, the active group –C=C– was introduced on the surface of CSW, and then the PMMA long chain polymer was grafted with an in‐situ polymerization to form a PMMA coating layer with a thickness of about 67 nm, which significantly improved the hydrophobicity of CSW surface.After modification with sodium oleate and PMMA grafting, the modified CSW significantly toughened and enhanced the mechanical properties of PP composites in the form of crack bridging, crack deflection and pull‐out effect. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Oil‐in‐oil nonaqueous emulsions are of great interest for developing emulsion‐templated polymers and encapsulation systems that are incompatible with water‐sensitive substances. Tailor‐made amphiphilic block copolymers are by far the most efficient stabilizers for oil‐in‐oil emulsions while less attention is given to copolymers with more complex architectures. Here, we report the stabilization of DMSO‐silicone oil interface by bottlebrush random copolymers (BRCPs) containing norbornene backbones with densely grafted poly(methyl methacrylate) (PMMA) and polystyrene (PS) side chains. The assembly kinetics of BRCPs at the DMSO‐silicone oil interface can be divided into three processes, including diffusion, reconfiguration and reorganization, and can be varied by tuning the degree of polymerization of the backbone (NB). Due to the high efficiency of BRCPs in reducing the interfacial tension, when using BRCPs as stabilizers, stable silicone oil‐in‐DMSO traditional emulsions and high internal phase emulsions (HIPEs) can be successfully obtained, while no stable emulsions can be achieved with linear PMMA‐b‐PS serving as the stabilizer. This study, for the first time, underscores the great potential of amphiphilic bottlebrush copolymers in preparing oil‐in‐oil emulsions. Given the advances in polymerization strategy, a broad variety of amphiphilic bottlebrush copolymers are expected to be synthesized and applied in the stabilization of nonaqueous biphasic systems. [ABSTRACT FROM AUTHOR]

Literature proves that the direct detection of 1O2(1Δg) at the solid gas interface is systematically performed from its phosphorescence using high intensity excitation sources (i.e., lasers), which lead to quasi‐ubiquitous chemical problems, such as sensitizer degradation, and photophysical counter‐active issues such as ultrafast exciton migration, singlet‐singlet and triplet‐triplet annihilation, and thermally activated delayed fluorescence mediated by 1O2(1Δg). To avoid these inconveniences, low excitation intensity is required but leads to serious analytical challenges. The best practices to reliably detect 1O2(1Δg) phosphorescence at various interfaces using a standard excitation source and near‐IR detector. The two main practices consist in a gas purging test for reliable identification of 1O2(1Δg), and in a particularly fine optimization of the angle made by excitation beam versus substrate plane. These practices are applied to porphyrin sensitizers H2TPP and ZnTPP, either neat or physiosorbed on glass, quartz, paper and hospital bandages, graphene oxide (GO), and embedded inside electrospun polystyrene fibers and spin coated poly(methyl methacrylate) films. Porphyrin‐based metal‐organic framework PCN‐224, freshly activated, is also examined. [ABSTRACT FROM AUTHOR]

The fabrication of cross-linked 1,10-diaminodecane-poly methyl methacrylate/carbon nanotubes/graphene nanocomposites PMMA/CNTs/GNP(a–c) has been executed effectively using a multistep chemical cross-linking reaction. The environmental response of the fabricated material has been extensively investigated. The synthesized PMMA@CNTs/GNP nanocomposite effectively removed crystal violet (CV) and methylene blue (MB) from the simulated textile wastewater solution. The comprehensive delineation of the prepared nanocomposite was examined using SEM, X-ray diffraction (XRD), and FTIR analysis. The outcomes revealed that adsorption capacity was influenced by six variables (e.g., contact duration, starting concentration, adsorbent mass, the effect of the solution pH, temperature, and the impact of KNO3). Additionally, studies on thermodynamics and isotherm have been published. The elimination process involves chemical adsorption based on the pseudo-second-order kinetics model. This model predicted that the maximal adsorption capacities of the MB and CV dyes would be 20.83 and 22.42 mg g−1, respectively, best fitting the experimental results. This work is a pilot case study highlighting the outstanding potential of PMMA/CNTs/GNP nanocomposites as materials for CV and MB dye elimination. [ABSTRACT FROM AUTHOR]

Smart polymers undergo significant physical or chemical changes in response to stimuli like temperature and pH. Achieving a narrow molecular weight distribution is crucial for their sensitivity. Reversible addition–fragmentation chain transfer (RAFT) in ionic liquids is an effective method for synthesizing such polymers due to its favorable kinetics and environmental benefits. Most studies use imidazolium ionic liquids, while pyridinium ionic liquids are less common despite their easy synthesis. This study reports the first successful RAFT copolymerization of di(ethylene glycol) methyl ether methacrylate (DEGMEMA) and methyl methacrylate in N‐hexylpyridinium hexafluorophosphate ([HPY][PF6]). Both linear and hyperbranched copolymers (Mn > 25,000) with narrow molecular weight distribution were synthesized, showing observable temperature responses and biocompatibility. The linear copolymers had a desirable dispersity (Ð) of less than 1.10, while the hyperbranched copolymer had a Ð of 2.034. The lower critical solution temperatures (LCSTs) of the copolymers were close to or below the LCST of PDEGMEMA (26°C). This study indicates that pyridinium ionic liquids can be explored as a suitable solvent for synthesizing methacrylate‐based smart polymers. [ABSTRACT FROM AUTHOR]

In the study, a new strategy is presented to make PLGA (poly lactic‐co‐glycolic acid) and POEGMEMA (poly(oligo(ethylene glycol) methyl ether methacrylate)) based biodegradable and biocompatible tissue scaffold via a new physical cross‐linking method. The advantage of brushed structure of POEGMEMA polymer and the hydrophobic character of PLGA polymer is taken to make physically entangled network in aqueous media. The hydrophobic nature of PLGA allows to get scaffolds even at low ratio of PLGA (25%, w/w) when using POEGMEMA (yield: 86%). This strategy gives robust polymeric networks in aqueous media without using chemical reactions through high hydrophilic polymer content. Scaffolds with high POEGMEMA ratio (75%, w/w) show two times higher water uptake ratio (≈300%) and two times lower compression strength (19 kPa) compared to the ones with lower POEGMEMA content (50%, w/w). They also show desired degradation profiles in various aqueous solutions. While the scaffolds prepared with 25% and 50% PLGA are almost stable in first 20 days, they completely degrade in 40–50 days. Both scaffold formulations (25% PLGA‐75% POEGMEMA and 50% PLGA‐50% POEGMEMA) have similar proliferative properties for fibroblast cells. The scaffolds also do not show toxicity compared to control group according to live‐dead assay. [ABSTRACT FROM AUTHOR]

The enhanced and direct immobilization of the enzyme horseradish peroxidase on poly(methyl methacrylate) (PMMA) microchannel surfaces to create a miniaturized enzymatic reactor for the biocatalytic oxidation of phenols is demonstrated. Enzyme immobilization occurs by physical adsorption after oxygen plasma treatment, which micro-nanotextures the PMMA surfaces. A five-fold enhancement in immobilized enzyme activity was observed, attributed to the increased surface area and, therefore, to a higher quantity of immobilized enzymes compared to an untreated PMMA surface. The enzymatic reaction yield reached 75% using a flow rate of 2.0 μL/min for the reaction mixture. Additionally, the developed microreactor was reused more than 16 times without affecting the enzymatic conversion yield. These results demonstrate the potential of microchannels with plasma micro/nanotextured surfaces for the rapid and facile fabrication of microfluidic enzymatic microreactors with enhanced catalytic activity and stability. [ABSTRACT FROM AUTHOR]

Thermal frontal polymerization (FP) of acrylate monomers mixed with conventional peroxide initiators leads to significant bubble formation at the polymerizing front, limiting their practical applications. Redox initiators present a promising alternative to peroxide initiators, as they prevent the formation of gaseous byproducts during initiator decomposition and lower the front temperature, thereby enabling bubble-free FP. In this study, we investigate the FP of acrylate monomers of varying functionalities, including methyl methacrylate (MMA), 1,6-hexanediol diacrylate (HDDA), and trimethylolpropane triacrylate (TMPTA), using N,N-dimethylaniline/benzoyl peroxide (DMA/BPO) redox couple at room temperature and compare their front behavior, pot life, and bubble formation with those of same resin systems mixed with a conventional peroxide initiator, Luperox 231. The use of redox couples in FP of acrylates shows promise for rapid, energy-efficient manufacturing of polyacrylates and can enable new applications such as 3D printing and composite manufacturing. [ABSTRACT FROM AUTHOR]

In this study, specific additives were incorporated in polyhydroxyalcanoate (PHB) and polylactic acid (PLA) blend to improve its compatibility, and so enhance the cell metabolic activity of scaffolds for tissue engineering. The formulations were manufactured through material extrusion (MEX) additive manufacturing (AM) technology. As additives, petroleum-based poly(ethylene) with glicidyl metacrylate (EGM) and methyl acrylate-co-glycidyl methacrylate (EMAG); poly(styrene-co-maleic anhydride) copolymer (Xibond); and bio-based epoxidized linseed oil (ELO) were used. On one hand, standard geometries manufactured were assessed to evaluate the compatibilizing effect. The additives improved the compatibility of PHB/PLA blend, highlighting the effect of EMAG and ELO in ductile properties. The processability was also enhanced for the decrease in melt temperature as well as the improvement of thermal stability. On the other hand, manufactured scaffolds were evaluated for the purpose of bone regeneration. The mean pore size and porosity exhibited values between 675 and 718 μm and 50 and 53%, respectively. According to the results, the compression stress was higher (11–13 MPa) than the required for trabecular bones (5–10 MPa). The best results in cell metabolic activity were obtained by incorporating ELO and Xibond due to the decrease in water contact angle, showing a stable cell attachment after 7 days of culture as observed in SEM. [ABSTRACT FROM AUTHOR]

Due to energy shortages and the greenhouse effect, the efficient use of energy through phase-change materials (PCMs) is gaining increased attention. In this study, magnetic phase-change microcapsules (Mag-mc) were prepared by suspension polymerization. The shell layer of the microcapsules was formed by copolymerizing methyl methacrylate and triethoxyethylene silane, with the latter enhancing the compatibility of the shell layer with the magnetic additive. Ferric ferrous oxide modified by oleic acid (Fe3O4(m)) was added as the magnetic additive. Differential scanning calorimetry (DSC) testing revealed that the content of phase-change materials in microcapsules without and with ferric ferrous oxide were 79.77% and 96.63%, respectively, demonstrating that the addition of Fe3O4(m) improved the encapsulation efficiency and enhanced the energy storage ability of the microcapsules. Laser particle size analysis showed that the overall average particle sizes for the microcapsules without and with ferric ferrous oxide were 3.48 μm and 2.09 μm, respectively, indicating that the incorporation of magnetic materials reduced the size and distribution of the microcapsules. Thermogravimetric analysis indicated that the thermal stability of the microcapsules was enhanced by the addition of Fe3O4(m). Moreover, the infrared emissivity of the microcapsule-containing film decreased from 0.77 to 0.72 with the addition of Fe3O4(m) to the shell of microcapsules. [ABSTRACT FROM AUTHOR]

Lithium‐metal batteries (LMBs) are considered one of the most promising next‐generation high‐energy‐density battery systems. However, the leakage problem and fire hazard of commercial liquid electrolytes hinder their practical applications. Herein, a flame‐retardant solid polymer electrolyte (FRSPE) is fabricated by in situ polymerization of methyl methacrylate (MMA), allyl diglycol carbonate (ADC), and flame‐retardant monomer, i.e., diethyl vinyl phosphonate (DEVP), in which the phosphorus is chemically bonded to the polymer matrix to avoid the parasitic reaction between flame‐retardant molecules with lithium (Li) anode. Compared with the previously reported solid polymer electrolytes (SPEs) possessing free phosphorus, significantly increased efficiency of flame‐retardant and improved electrochemical performance can be achieved. With a wide electrochemical window (≈4.4V), high ionic conductivity (1.8 × 10−4 S cm−1), and superior compatibility with Li anode, the assembled Li/FRSPE/LiFePO4 (LFP) cell exhibits stable cycling over a wide temperature range (capacity retention of 70.9%@1000 cycles and 69.1%@200 cycles at 25 and 80 °C, respectively). Furthermore, the high‐voltage full cells, e.g., Li/LiCoO2 (LCO) and Li/LiNi0.8Co0.1Mn0.1O2 (NCM811), with FRSPE also deliver excellent cycling performance. The current design principle with flame‐retardant chemically bonded in the polymer framework can provide a new pathway for developing practical, safe, and stable LMBs. [ABSTRACT FROM AUTHOR]

This study introduces bis(1‐cyanocyclohex‐1‐yl)trithiocarbonate (TTC‐bCCH) as a novel trithiocarbonate chain transfer agent and compares its reactivity with the previously described bis(2‐cyanopropan‐2‐yl)trithiocarbonate (TTC‐bCP) for the reversible addition‐fragmentation chain transfer (RAFT) polymerization of styrene (St), n‐butyl acrylate (nBA), and methyl methacrylate (MMA). Significant findings include the effective control of Mn and low dispersities from the onset of polymerization of St and nBA showing swift addition‐fragmentation kinetics, leading to similar behaviors between the two RAFT agents. In contrast, a fourfold decrease of the chain transfer constant to MMA is established for TTC‐bCCH over TTC‐bCP. This trend is confirmed through density functional theory (DFT) calculations. Finally, the study compares thermoplastic elastomer properties of all‐(meth)acrylic ABA block copolymers produced with both RAFT agents. The impact of dispersity of PMMA blocks on thermomechanical properties evaluated via rheological analysis reveals a more pronounced temperature dependence of the storage modulus (G′) for the triblock copolymer synthesized with TTC‐bCCH, indicating potential alteration of the phase separation. [ABSTRACT FROM AUTHOR]

Polymerization‐induced phase separation takes place when a miscible component of the monomer becomes immiscible as the polymer is formed. One example is the polymerization of methyl methacrylate (MMA) in the presence of poly(ethylene glycol) (PEG). Depending on the initial conditions, microscopic structures, including porous structures, co‐continuous monolith structures, and particle aggregation structures, are obtained. In this study, the phase separation process is analyzed using an optical microscope and fluorescence microscope. The nucleation or spinodal decomposition in the initial stage, subsequent growth in the microscopic domains, and eventual fixation of the structure are observed. The observed images are analyzed using image analysis software. The particle number and the particle size as a function of reaction time are evaluated. Conversion and molecular weight distribution as a function of reaction time are also analyzed. [ABSTRACT FROM AUTHOR]

A series of fluorescent carbazole‐coumarins exhibiting good photoluminescence quantum yields and thermally activated delayed fluorescence (TADF) properties have been designed and synthetized using computer‐aided density functional theory calculations. The TADF characteristics of the carbazole‐coumarins were systematically explored both in solution and in the solid state, utilizing poly(methyl methacrylate) (PMMA) as a matrix. The study revealed that the introduction of carbazole units onto the coumarin benzene ring led to compounds with thermally induced reverse intersystem crossing and delayed fluorescence. The study further demonstrated the potential utility of these compounds in practical applications by incorporating them into a Cmr‐PMMA‐based sensor for molecular oxygen detection. The resulting sensor exhibited promising performance, highlighting the adaptability and efficacy of the synthesized TADF‐carbazole‐coumarin compounds for reversible molecular oxygen sensing. [ABSTRACT FROM AUTHOR]

Cancer is ranked among the top causes of mortality throughout the world. Conventional therapies are associated with toxicity and undesirable side effects, rendering them unsuitable for prolonged use. Additionally, there is a high occurrence of resistance to anticancer drugs and recurrence in certain circumstances. Hence, it is essential to discover potent anticancer drugs that exhibit specificity and minimal unwanted effects. Curcumin, a polyphenol derivative, is present in the turmeric plant (Curcuma longa L.) and has chemopreventive, anticancer, radio-, and chemo-sensitizing activities. Curcumin exerts its anti-tumor effects on cancer cells by modulating the disrupted cell cycle through p53-dependent, p53-independent, and cyclin-dependent mechanisms. This review provides a summary of the formulations of curcumin based on nanospheres, since there is increasing interest in its medicinal usage for treating malignancies and tumors. Nanospheres are composed of a dense polymeric matrix, and have a size ranging from 10 to 200 nm. Lactic acid polymers, glycolic acid polymers, or mixtures of them, together with poly (methyl methacrylate), are primarily used as matrices in nanospheres. Nanospheres are suitable for local, oral, and systemic delivery due to their minuscule particle size. The majority of nanospheres are created using polymers that are both biocompatible and biodegradable. Previous investigations have shown that the use of a nanosphere delivery method can enhance tumor targeting, therapeutic efficacy, and biocompatibility of different anticancer agents. Moreover, these nanospheres can be easily taken up by mammalian cells. This review discusses the many curcumin nanosphere formulations used in cancer treatment. [ABSTRACT FROM AUTHOR]

Polymer composites containing poly (methyl methacrylate) (PMMA) and barium titanate (BaTiO3) were synthesized using the solution mixing method. The electrical conductivity of PMMA is 6 × 10−9 S/cm, and adding 2% fillers reduces to 5 × 10−9 S/cm. The melting point of PMMA is 373 °C, and adding 2% and 4% fillers increased it to 376 °C and 379 °C, respectively. The polymer chains become less mobile and block macromolecules on the filler surface. The modulus of elasticity and mechanical tensile stress of the polymer composites with a 5-wt% of BaTiO3 are 759.3 MPa and 75.6 MPa, respectively. The breakdown strength of PMMA is 203 KV and reduces with the addition of 5% filler to 144 KV. The values of Ec/Em evaluated using the Tsai-Pagano, Christensen-Waals, ROM, Mori-Tanaka, and Halpin-Tsai models underpredict the modulus compared to experimental Ec/Em values. Fourier spectroscopy confirmed the presence of Ti-O and BaTiO3 bonds in the polymer composite. Scanning electron microscope images reveal spherical aggregates of BaTiO3 coated with PMMA and an interparticle network. The dielectric constant of PMMA is 3 and increased with the addition of 2% and 4% fillers to 4 and 4.3, respectively. [ABSTRACT FROM AUTHOR]

The Expert Panel for Cosmetic Ingredient Safety (Panel) reviewed the safety of 30 vinylpyrrolidone polymers as used in cosmetic products; most of these ingredients have the reported cosmetic function of film former in common. The Panel reviewed data relevant to the safety of these ingredients, and determined that 27 vinylpyrrolidone polymers are safe in cosmetics in the present practices of use and concentration described in the safety assessment. The Panel also concluded that the available data are insufficient to make a determination that 3 vinylpyrrolidone polymers (all urethanes) are safe under the intended conditions of use in cosmetic formulations. [ABSTRACT FROM AUTHOR]

This study illustrates the impact of different polymer types on the characteristics of Fe2O3. The manufacture of nanocomposites involved the use of polyethylene oxide (PEO), polyvinyl alcohol (PVA), and Poly (methyl methacrylate) (PMMA) polymers. Nanocomposites were synthesised by combining an aqueous solution of Ferric chloride with various polymers. The Fe2O3 nanocomposite, which was polymer-based, was synthesised using an in situ chemical approach to investigate the impact of different polymer types on its primary physical characteristics. The configuration of polymer-based Fe2O3 nanocomposites was investigated using diagnostic instruments such as SEM, EDX, and XRD. The modification of the polymer had a clearly noticeable and apparent effect on the optical and structural properties of the nanocomposites. The utilisation of SEM, XRD, and EDX techniques provided confirmation of the successful synthesis of nanocomposites based on Fe2O3. The UV–visible spectra were examined to investigate the optical characteristics of the fabricated samples. The bandgaps of the nanocomposites ranged from 1.9 to 2.25 eV. The Urbach energy was also determined for all of the processed samples. [ABSTRACT FROM AUTHOR]

Our study aimed to evaluate the efficiency of solar power systems by developing dye-sensitized solar cells (DSSCs) with an electrolyte of carbon nanotubes (CNTs) dispersed in poly (methyl methacrylate) (PMMA). Photovoltaic and impedance spectral studies showed that a polymer electrolyte with 3% carbon nanotubes resulted in an efficiency of solar power conversion of 7.40% and a photovoltaic current per unit cross-sectional area of 17.13 mA/cm2 in DSSCs. The optimal distribution of CNT fillers decreased the charge recombination of the titanium dioxide-dye-CNT-PMMA electrolyte surface. The X-ray diffraction spectrum showed characteristic peaks of PMMA and CNT at 28.6° and 63.0°, respectively, obtained in pure form and composites with dispersed carbon nanotubes. The peak intensity increased with the addition of CNTs in the polymer. A Fourier transform infrared spectroscopy investigation revealed the bonding within the CO and CH of PMMA and CNT to the polymer composite. The dielectric constant increased from 2.9 to 4.4, and the dielectric loss increased from 0.10 to 0.90 at 1 MHz for the dispersion of 6% CNT in PMMA. Scanning electron microscopy analysis showed that the internal particle structure and porosity had changed due to the presence of the CNTs in the PMMA. The dispersion of CNTs into the PMMA increased the maximum voltage of the polymer electrolytes. A breakdown voltage of 7.4 kV was attained with 6% CNTs in the polymer. [ABSTRACT FROM AUTHOR]

[Display omitted] Polymersomes are synthetic vesicles with potential use in healthcare, chemical transformations in confined environment (nanofactories), and in the construction of artificial cells and organelles. In this framework, one of the most important features of such supramolecular structures is the permeability behavior allowing for selective control of mass exchange between the inner and outer compartments. The use of biological and synthetic nanopores in this regard is the most common strategy to impart permeability nevertheless, this typically requires fairly complex strategies to enable porosity. Yet, investigations concerning the permeability of polymer vesicles to different analytes still requires further exploration and, taking these considerations into account, we have detailed investigated the permeability behavior of a variety of polymersomes with regard to different analytes (water, protons, and rhodamine B) which were selected as models for solvents, ions, and small molecules. Polymersomes based on hydrophilic blocks of poly[ N -(2-hydroxypropyl)methacrylamide] (PHPMA) or PEO (poly(ethylene oxide)) linked to the non-responsive blocks poly[ N -(4-isopropylphenylacetamide)ethyl methacrylate] (PPPhA) or poly(methyl methacrylate) (PMMA), or to the stimuli pH-responsive block poly[2-(diisopropylamino)ethyl methacrylate] (PDPA) have been investigated. Interestingly, the produced PEO-based vesicles are notably larger than the ones produced using PHPMA-containing block copolymers. The experimental results reveal that all the vesicles are inherently permeable to some extent with permeability behavior following exponential profiles. Nevertheless, polymersomes based on PMMA as the hydrophobic component were demonstrated to be the least permeable to the small molecule rhodamine B as well as to water. The synthetic vesicles based on the pH-responsive PDPA block exhibited restrictive and notably slow proton permeability as attributed to partial chain protonation upon acidification of the medium. The dye permeability was evidenced to be much slower than ion or solvent diffusion, and in the case of pH-responsive assemblies, it was demonstrated to also depend on the ionic strength of the environment. These findings are understood to be highly relevant towards polymer selection for the production of synthetic vesicles with selective and time-dependent permeability, and it may thus contribute in advancing biomimicry and nanomedicine. [ABSTRACT FROM AUTHOR]

Liquid phase exfoliation of non-van der Waals materials has generated renewed interest in fundamental optical and electronic materials discovery and processing. However, such approaches can limit access to novel two-dimensional materials due to the chemistry of exfoliation and processing conditions employed (e.g., processing temperature, mechanical energy input, volatile organic compounds, and sensitive redox chemistries). Here, we demonstrate the exfoliation of bulk hematite (α-Fe2O3) powder using a mild bath sonication methodology in liquid monomer media to form stable colloidal dispersions with quasi-two-dimensional hematene nanoflakes. These colloidal dispersions were further processed to form hematene poly(methyl methacrylate) matrix composite substrates. [ABSTRACT FROM AUTHOR]

Clusterization‐triggered emissive (CTE) materials have attracted great attention in recent years. The regulation of the emission property of materials with CTE property through supramolecular interactions is an excellent strategy for the construction of smart fluorescent materials. In this work, we have prepared a regulatable supramolecular polymer network with CTE properties through pillararene‐based host−guest interactions. The pillar[5]arene‐grafted poly(methyl methacrylate) (PMMA) showed a classic CTE character. After adding Brooker's merocyanine‐grafted polymer to the solution of the pillar[5]arene‐containing PMMA, the supramolecular polymer network gel formed by the host−guest interactions between pillararene and Brooker's merocyanine guest. This supramolecular network showed brighter fluorescence than the pillar[5]arene‐grafted PMMA in the solid state. In addition, the fluorescence emission of the supramolecular network can be further regulated by pH conditions. After adding an acid, the Brooker's merocyanine‐containing guest polymer was protonated, and the supramolecular network changed to a protonated network through host−guest interactions between protonated Brooker's merocyanine guest and pillararene. Interestingly, the fluorescence was quenched when the supramolecular network turned into the protonated network. After adding a base, the protonated network can convert back to the original network, along with recovery of the fluorescence. Therefore, the regulation of the fluorescence of the supramolecular polymer materials with CTE was successfully realized by pillararene‐based host−guest interactions. Furthermore, this tailorable fluorescent supramolecular polymer network system was applied as an information encryption material. [ABSTRACT FROM AUTHOR]

The current study aims to develop isolation protocols for several contaminants of emerging concern (i.e., microplastics (MPs), polycyclic aromatic hydrocarbons (PAHs), and heavy metals (HMs)) from different commercial brands and raw milk samples and also to quantify and characterize the risks of these contaminants pose to human health. The quantification, shape, color, and chemical composition of MPs were achieved using optical microscopy, micro-Fourier transform infrared spectroscopy, and scanning electron microscopy coupled with energy-dispersive spectroscopy. Based on the MP dimensions highlighted by the aforementioned techniques, it can be stated that their length ranges between tens of micrometers and a few centimeters; plus, the thickness in some cases reaches more than 15 µm, and the structure of the MPs can be mostly described as a fibriform with a glossy/matte aspect. The polymeric structures identified were polyamides, poly(methyl methacrylate), polyurethane, polyester, and polyethylene. Chemical investigations (PAHs and HMs concentrations) were performed by high-performance liquid chromatography with fluorescence detection and inductively coupled plasma mass spectrometry, respectively. The pollution load index (1.091–7.676) and daily intake of MPs for adults (0.021–1.061 n·kg−1·d−1) and children (0.089–4.420 n·kg−1·d−1) were calculated. It can be concluded that the presence of MPs in milk supports the hypothesis that microplastics can act as carriers for other contaminants (HMs and PAHs), thus increasing the threat to health. [ABSTRACT FROM AUTHOR]

The aim of the present in vitro comparative study is to validate a novel composite polymer, named "ONLY", developed to overcome the mechanical drawbacks of conventional, metal-reinforced poly(methyl methacrylate) (PMMA) interim restoration. Ten interim restorations were designed and fabricated (five in the composite "ONLY" group, and five in the metal-reinforced PMMA group). All the samples were screwed into the prototype models, simulating a complete edentulous mandible rehabilitated with six straight implants. Outcome measures were break point (load, N) and displacement (mm) through a static compression test, and material behavior through a dynamic cyclic test method (fatigue test). A total of 20 samples were tested (10 for static and 10 for dynamic). In each group, five samples (test and control) were used. All the specimens completed the mechanical tests, as planned. There was no statistically significant difference between groups for any test. In the test group, the break point was 1953.19 ± 543.73 N, while it was 2031.10 ± 716.68 N in the control group (p = 0.775). The displacement was 1.89 ± 0.34 mm in the test group and 1.98 ± 0.75 mm in the control group (p = 0.763). Using the dynamic cyclic test method, in the control group the mean load was 2504.60 ± 972.15 N, while in the test group the mean load was 3382.00 ± 578.50 N. The difference between groups was 877.40 ± 579.30 N (p value = 0.121). Within the limitations of this in vitro study, the novel composite polymer can be used to immediately load dental implants. Further clinical research is needed to confirm these preliminary results. [ABSTRACT FROM AUTHOR]

In this study, we demonstrated that adding 0.05 wt.% cellulose nanofibers (CNFs) to CNFpoly(methyl methacrylate) (PMMA) composite materials enhanced hardness, toughness, and maximum flexural strength, surpassing commercially available PMMA variants. Furthermore, CNF addition substantially improved PMMA's wear resistance, reducing wear volume through increased hardness and CNF's lubricating effect. The observed variation in slope in the wear volume versus dissipated energy plot suggests different wear mechanisms, and the potential to serve as a sensor for detecting wear interface behavior. [ABSTRACT FROM AUTHOR]

The authors studied Poly (methyl methacrylate) also called PMMA films with different concentrations of Poly (9, 9′-di-n-octylfuorenyl-2, 7-diyl) also called PFO and concluded that 1% PFO blended with PMMA is the best choice for opto-electronic applications. In the present study, the authors prepared nanocomposite films of PMMA + 1% PFO + different concentrations of TiO2 nanoparticles. The resulting films were subjected to FTIR, XRD, UV–visible, fluorescence and electrical conductivity studies. The polymer matrix undergoes modifications in its molecular and microstructural characteristics as evidenced by FTIR and XRD results. The addition of TiO2 nanoparticles leads to a uniform dispersion and good interaction with the blend matrix resulting in homogeneous films. The additional peaks were found at a wavenumber of 3620 cm−1 in FTIR can be attributed to stretching vibration of TiO2. The presence of TiO2 nanoparticles is confirmed by the distinctive diffraction peaks observed at 25.4°, 37.8°, 48.3°, 54.3°, 55.2°, and 62.8°. With a shift in the absorption peak towards higher wavelengths, the nanocomposites show greater absorption in the UV and visible regions. As the concentration of TiO2 increases, the optical parameters such as absorption coefficient, extinction coefficient, Urbach energy, refractive index and optical conductivity also increase. The direct optical band gap of the PNC films decreases from 5.03 to 3.06 eV and indirect band gap decreases from 4.52 to 1.92 eV at 10 wt% of TiO2 concentration. The addition of TiO2 nanoparticles to the PFO/PMMA matrix resulted in an increase in fluorescence emission intensity. The AC electrical conductivity exhibits increasing trend with frequency in Audio-Frequency range. Thus TiO2 nanoparticles improve the overall optical, electrical, and structural properties of PFO-PMMA nanocomposites. This means that they can be used in a variety of optoelectronic and advanced optical devices. [ABSTRACT FROM AUTHOR]

A novel hydrophobic association copolymer (PAMA) was synthesized by incorporating acrylamide (AM), 2-acrylamide-2-methylpropanesulfonic acid (AMPS), cationic monomer (MEDDA), and methyl methacrylate (MMA). The properties of MMA copolymers with varying contents were analyzed using infrared spectroscopy, nuclear magnetic resonance spectroscopy, and scanning electron microscopy. Optimal overall performance of the solution was achieved when the MMA content reached 1.4 % w/w. Compared to pure PAAM (without MMA), the PAMA-1.4 % polymer exhibited superior viscoelasticity, temperature resistance, and shear resistance. This enhancement in PAMA performance can be attributed to the significant inhibition of intermolecular water film formation within the polymer matrix by MMA, effectively improving and regulating solution solubility while strengthening molecular chain interactions and enhancing the structural network strength of PAMA polymers. Additionally, the inclusion of MMA transformed rock surfaces from non-wetting to wetting conditions, thereby greatly improving oil displacement efficiency. In displacement experiments, PAMA-1.4 % performed better in terms of enhanced oil recovery, the recovery rate of 0.1 % w/w PAMA-2.4 % solution is only 7.78 %, while the recovery rate of 0.1 % w/w PAMA-1.4 % solution is 13.06 %. [ABSTRACT FROM AUTHOR]

Förster resonance energy transfer (FRET) is an established tool for measuring distances between two molecules (donor and acceptor) on the nanometer scale. In the field of polymer science, the use of FRET to measure polymer end‐to‐end distances (Ree) often requires complex synthetic steps to label the chain ends with the FRET pair. This work reports an anthracene‐functionalized chain‐transfer agent for reversible addition‐fragmentation chain‐transfer (RAFT) polymerization, enabling the synthesized chains to be directly end‐labeled with a donor and acceptor without the need for any post‐polymerization functionalization. Noteworthily, this FRET method allows for chain conformation measurements of low molecular weight oligomers in situ, without any work‐up steps. Using FRET to directly measure the average Ree of the oligomer chains during polymerization, the chain growth of methyl methacrylate, styrene, and methyl acrylate is investigated as a function of reaction time, including determining their degree of polymerization (DP). It is found that DP results from FRET are consistent with other established measurement methods, such as nuclear magnetic resonance (NMR) spectroscopy. Altogether, this work presents a broadly applicable and straightforward method to in situ characterize Ree of low molecular weight oligomers and their DP during reaction. [ABSTRACT FROM AUTHOR]

AbstractElectrochromic devices (ECDs) have broad application prospects in smart windows, low-power displays, anti-glare rearview mirrors, and so on. The electrolyte layer is one of the crucial components of ECDs acting as an interface layer between two electrodes to provide ions transport. Conventional liquid electrolytes have disadvantages of easy leakage, low safety and complex encapsulation, while inorganic solid electrolytes (ISEs) have very poor room temperature conductivity. Polymer electrolytes are composites consisting of polymeric matrices, solvents, conductive salts and curing agents, including solid polymer electrolytes (SPEs), gel polymer electrolytes (GPEs) and composite polymer electrolytes (CPEs). They are widely used in ECDs because of their excellent ionic conductivity, superior electrochemical stability, high transparency and simplicity of processing. This review provides a detailed discussion of the types, mechanisms, characteristics and preparation methods of polymer electrolytes for ECDs. The latest research progresses in the design and application of CPEs based on poly(ethylene oxide) (PEO), poly(methyl methacrylate) (PMMA), poly(vinylidene fluoride) (PVDF) and poly(vinyl alcohol) (PVA) are highlighted, and the potential applications of polymer electrolytes in the field of electrochromism are reviewed. Furthermore, the future development of polymer electrolytes in ECDs with stability, significant coloration efficiency and high ionic conductivity is discussed. [ABSTRACT FROM AUTHOR]

Objective: To determine the effects of adding a quaternary ammonium methacryloxy silicate (K18) and K18-functionalized filler (K18-Filler) on the material and antimicrobial properties of a hard denture reline material. Materials and methods: 30% K18 in methyl methacrylate (K18-MMA; 0–20 wt% of reliner) and K18-Filler (0–30 wt% of reliner) were incorporated into KoolinerTM hard denture reliner. KoolinerTM served as the control. The cure (Shore A hardness), hydrophilicity (contact angles), mechanical (3-point bend test), water sorption, and antimicrobial properties against Streptococcus mutans, S. sanguinis, and Candida albicans were determined. Results: Most K18 groups cured well and had comparable Shore A hardness values (range ~52 to 70 DHN) to that of controls (67.2 ± 1.8 DHN; Bonferroni corrected p > 0.0003). Even the softest group had hardness values within the range of commercial products. Half of the K18 groups had comparable contact angles to that of controls (range ~75° to 80° vs 83.41° ± 2.66°; Bonferroni corrected p > 0.0003), and most were within the range of commercial liners. K18-MMA and K18-Filler increased modulus but decreased ultimate transverse strength (UTS). All experimental groups had comparable or higher moduli than controls (range ~966 to 2069 MPa vs 1340 ± 119 MPa; Bonferroni corrected p < 0.0003), but only half of the experimental groups had comparable UTS to that of controls (range ~41 to 49 MPa vs 55.8 ± 1.5 MPa; Bonferroni corrected p > 0.0003). The 15% and 20% K18-MMA with 30% K18-Filler groups had significant antimicrobial activity against all three microbes (p < 0.05). However, the 15% and 20% K18-MMA with 30% K18-Filler groups had significantly higher water sorption at early time points (p < 0.05). After 8 weeks, they were comparable to each other (p > 0.05). Conclusions: K18-MMA and K18-Filler are promising antimicrobial additives that produce hard denture liners with material properties within the range of commercial products and significant antimicrobial properties against S. mutans, S. sanguinis, and C. albicans. Further development is needed to reduce water sorption. [ABSTRACT FROM AUTHOR]