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Purpose: To compare the color dimensions, color discrepancies (E00), and surface roughness of milled materials before and after application of a bleaching agent. Materials and Methods: A total of 10 extracted molars were obtained. Each tooth was cut in transverse sections to create disks (3-mm thick, 10-mm diameter; control group). Disk specimens of eight materials (n = 10 per group) were fabricated: polymethyl methacrylate (PMMA) interim material (PMMA-Telio group), two resin nanoceramics (RNC-Ultimate group and RNC-Cerasmart group), two hybrid ceramics (HC-Shofu group and HC-Enamic group), lithium disilicate (LD-Emax group), zirconia-reinforced glass ceramic (ZGC-Suprinity group), and zirconia (Zr-InCeram group). Color measurements were obtained using a spectrophotometer before and after applying 35% hydrogen peroxide-based bleaching agent. Pre- and postbleaching surface roughness (Sa) analyses were completed using a profilometer. Results: Significant L*, a*, b*, and E00 value differences were found (P < .05). Color discrepancies (E00) ranged from 0.30 ± 0.14 to 4.82 ± 0.10. The highest color discrepancies were measured on the PMMA-Telio group, while the lowest color discrepancies were computed for ZGC-Suprinity, RNCUltimate, and RNC-Cerasmart. Significant surface roughness differences were found (P < .05). The largest increase of surface roughness values between the pre- and postbleaching measurements was obtained in the PMMA-Telio group with a mean Sa value of 4.73 ± 3.02, while the largest decrease of surface roughness values between the pre- and postbleaching measurements was obtained in the Zr-InCeram group with a mean Sa value of -1.58 ± 0.10. Conclusions: The milled materials showed significant pre- and postbleaching color and surface roughness discrepancies. [ABSTRACT FROM AUTHOR]

Traditionally, metal-ceramics, metal-reinforced acrylics, and--more recently--full-contour or layered zirconia have been the materials of choice for definitive fixed implant-supported rehabilitations. Polymethyl methacrylate (PMMA) is commonly used in implant dentistry for the fabrication of implant-supported interim prostheses and as milled or 3D-printed prototypes. This article describes a novel protocol to prosthetically restore a completely edentulous patient following a digital workflow, with fixed, screw-retained, implant-supported prostheses fabricated from CAD/CAM milled PMMA, with no metal substructure. After a 2-year follow-up in terms of esthetics, phonetics, function, and biologic tissue response, the outcome remains functional and free of mechanical, biomechanical, or biologic complications. The aim of this article is to illustrate the feasibility of using milled PMMA as a viable definitive prosthetic material for the fixed implant rehabilitation of edentulous patients. [ABSTRACT FROM AUTHOR]

Neutrophils are the first line of defense of the innate immune system. In response to methicillin-resistant Staphylococcus aureus infection in the skin, hematopoietic stem, and progenitor cells (HSPCs) traffic to wounds and undergo extramedullary granulopoiesis, producing neutrophils necessary to resolve the infection. This prompted the engineering of a gelatin methacrylate (GelMA) hydrogel that encapsulates HSPCs within a matrix amenable to subcutaneous delivery. The authors study the influence of hydrogel mechanical properties to produce an artificial niche for granulocyte-monocyte progenitors (GMPs) to efficiently expand into functional neutrophils that can populate infected tissue. Lin-cKIT+ HSPCs, harvested from fluorescent neutrophil reporter mice, are encapsulated in GelMA hydrogels of varying polymer concentration and UV-crosslinked to produce HSPC-laden gels of specific stiffness and mesh sizes. Softer 5% GelMA gels yield the most viable progenitors and effective cell-matrix interactions. Compared to suspension culture, 5% GelMA results in a twofold expansion of mature neutrophils that retain antimicrobial functions including degranulation, phagocytosis, and ROS production. When implanted dermally in C57BL/6J mice, luciferase-expressing neutrophils expanded in GelMA hydrogels are visualized at the site of implantation for over 5 days. They demonstrate the potential of GelMA hydrogels for delivering HSPCs directly to the site of skin infection to promote local granulopoiesis.

In this work, a low-profile optical transparent wideband metamaterial absorber based on radiation–absorption reciprocal theory is proposed. The top layer and bottom layer are composed of indium tin oxide–polyethylene terephthalate films, and the middle layer is a transparent substrate polymethyl methacrylate. The method of transparent wideband absorption using reciprocal theory is proposed to guide the design. Based on characteristic mode analysis and calculated equivalent aperture efficiency, the absorber consisting of composite resonators is analyzed and designed. The equivalent circuit model and surface current distributions are studied to verify the design. The numerical results show that high absorption of greater than 90% in the frequency range of 5.7–16.4 GHz is obtained. A wideband absorption rate of greater than 80% at a 60° incident angle under TM polarization and an absorption rate of greater than 65% at a 60° incident angle under TE polarization are obtained. The proposed design has the advantages of broadband absorption, polarization insensitivity, light transmittance of more than 70%, and compact structure, which can be applied to special scenes that require optical transparency, such as anechoic chamber glass and cockpit glass. [ABSTRACT FROM AUTHOR]

Purpose: To assess two types of abutment materials routinely used in daily practice--direct polymethyl methacrylate (PMMA) and a zirconia-on--Ti-base abutment--and their effects on peri-implant soft tissues and bone remodeling in a minipig model. Materials and Methods: A total of 40 implants were placed in five minipigs in a single-stage surgery. Four different types of abutment materials (n = 10 per group) were used: (1) titanium (control); (2) zirconia (control); (3) PMMA (test 1); and (4) Ti-base (zirconia bonded to a titanium framework; test 2). After 3 months of healing, the samples were collected and subjected to nondecalcified histology. The soft tissue dimensions (sulcus, junctional epithelium, and connective tissue attachment) were assessed on each abutment mesially and distally, and the distance from the implant margin to the first boneto-implant contact (BIC) was measured. Results: No statistically significant differences were found among the four groups regarding soft tissue dimensions (P = .21), and a long junctional epithelium (mean: 4.1 mm) and a short connective tissue attachment (mean: 0.3 mm) were found in the majority of abutments. In some samples, the junctional epithelium extended all the way to the bone level. The measured peri-implant bone remodeling was similar in all four groups (P = .25). Conclusions: The present findings indicate that both direct PMMA and zirconia-on-Ti-base abutments seem to allow soft tissue integration similar to that of titanium and zirconia abutments. However, clinical studies are warranted to either confirm or refute the observed findings and to further investigate the influence of different materials on mucointegration. [ABSTRACT FROM AUTHOR]

The shock-to-detonation transition properties of the triaminotrinitrobenzene based PBX 9502 high explosive (HE) are experimentally and computationally explored in extremely high input pressure conditions. These include both slightly sub-Chapman–Jouguet and overdriven input pressure conditions, namely, ∼ 25 and ∼ 31 GPa, respectively. Our experiments capture the transient buildup of a shock-induced reaction via measurement of HE and polymethyl methacrylate window interface particle velocity profiles for a variety of sample thicknesses for this insensitive HE. These observations necessitate extremely thin explosive samples, and the high rates of reaction provide a considerable challenge to optical diagnostics. Samples at these thicknesses also provide an opportunity for evaluation of potential micro-structure effects on the resulting shock-to-detonation-transition measurements. To address this, the thin samples are also characterized via x-ray micro-computed tomography. Finally, a pair of previously established continuum-level detonation performance modeling approaches for PBX 9502 were used to analyze the experiments. The employed model variants crucially differ in their definition of each model's empirical reaction rate functional form, utilization of shock state quantities, and local flow variable dependencies. As a result, the present experiments provide a novel platform to evaluate the quantitative and qualitative consequences stemming from these modeling choices in a challenging initiation scenario, largely beyond the chosen calibration range of either model. This new experimental information will provide a platform for both improved physics and model parameterizations for this well-studied explosive. [ABSTRACT FROM AUTHOR]

A self‐assembled "caging" strategy is presented for the safe delivery of potent cationic antimicrobials that suffer from non‐specific toxicity for the effective treatment of in vivo systemic bacterial infection. The key development here is a new block copolymer consisting of a poly(ethylene glycol) (PEG) stealth block and an anionic and lipase‐degradable block of poly(ɛ‐caprolactone) (PCL) and phosphonic acid‐bearing methacrylate copolymer, synthesized by hybrid copolymerization of methacrylate and cyclic esters. The anionic blocks electrostatically interact with cationic antimicrobials to form neutrally charged polyion complexes with the PEG blocks on the surface. The PCL component imparts the nanocomplex with biodegradability by bacterial secretory lipase. In the proof‐of‐concept study, cationic polyimidazolium that shows excellent antibacterial activity but severe toxicity is packaged by the block copolymer into nanocomplexes, which are stable in complex environments of high salt and protein concentrations and released the antimicrobials upon degradation of the copolymer by bacteria‐secreted lipase. The "caging" formulation of polyimidazolium eliminated its toxicity and led to highly effective bactericidal performance comparable to free polyimidazolium. This caging strategy does not require sophisticated chemical modification of cationic antimicrobials, offering a broadly applicable formulation strategy to overcome their common toxicity issue that has become a primary translational barrier. [ABSTRACT FROM AUTHOR]

Porous radiative cooling polymers have drawn significant attention for passive daytime cooling due to their desirable cooling performance and easy scalability. Since optimal pore parameters (i.e., pore diameter and porosity) will enhance light scattering, polymethyl methacrylate (PMMA) powders are sintered to fabricate samples with different pore parameters by the one‐step full‐dry powder sintering method. These samples have a hierarchically porous structure with pore diameters <5.0 µm. The most porous sample has 43% porosity, 0.964 reflectance in the 0.3–2.5 µm wavelength range, and 0.967 emittance in 8–13 µm wavelength range (which is the atmospheric window). The measured cooling temperature difference decreases when the porosity is low for hierarchically porous PMMA with similar pore size distribution. The high sub‐ambient cooling temperature reduction provided by hierarchically porous PMMA with optimal pore parameters is due to high solar reflectance when illuminated by the sun. Similar cooling trends are evident when sunlight is simulated by a Xenon lamp and an optical filter. The powder‐sintered hierarchically porous PMMA with optimal pore parameters can be an excellent radiative cooler for passive daytime cooling applications. [ABSTRACT FROM AUTHOR]

Developing functional adhesives combining strong adhesion, good recyclability and diverse harsh‐condition adaptability is a grand challenge. Here, we introduce a general dendritic molecule doping strategy to activate commercial polymers into a new family of supramolecular adhesives integrating high adhesion strength, ultralow temperature, water resistant and multi‐reusable properties. Our method involves rational design of a new rigid‐flexible coupled dendritic molecule—M4C8OH as a versatile dopant, while simple M4C8OH doping into commercial polymers can modulate internal and external non‐covalent interaction to enable H‐bonding enhanced interchain cross‐linking for tough cohesion along with enhanced interphase interaction. This endows 20 wt % M4C8OH‐doped polycaprolactone (PCL) adhesives (PCL‐M4C8OH) with improved adhesion strength on various substrates with the maximum increase up to 2.87 times that of PCL. In particular, the adhesion strengths of PCL‐M4C8OH on polymethyl methacrylate at 25 °C and −196 °C reach 4.67 and 3.58 MPa—1.9 and 2.3 times those of PCL and superior to diverse commercial adhesives and most reported adhesives. PCL‐M4C8OH also displays markedly‐improved multi‐usability and tolerance against ultralow temperature and diverse wet environments. Mechanism studies reveal the crucial role of M4C8OH molecular structures toward superior adhesion. Our method can be expanded to other polymer matrices, yielding diverse new supramolecular adhesives. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of adding cholesteryl methacrylate (CM) monomer to experimental composite resins and evaluate its impact on polymerization shrinkage force (PSF), Knoop microhardness (KHN), sorption and solubility (SS), vulnerability to spontaneous oxidation (VOE), porosity (BES), viscosity (V), and cross-link density (CLD). CM was synthesized, mixed with varying proportions of Bis-GMA, 70 wt% filler particles, and 40 % TEGDMA. The groups tested were: CM0 (60 % Bis-GMA), CM6 (54 % Bis-GMA/6 % CM), CM12 (48 % Bis-GMA/12 % CM), CM18 (42 % Bis-GMA/18 % CM) and CM24 (36 % Bis-GMA/24 % CM). The PSF was evaluated using a universal testing machine. KHN was measured with a 50 g load for 30 s. SS was determined according to ISO 4049:2009. VOE was measured with a three-electrode system in an electrochemical cell. BES images were obtained using an electron microscope to assess porosity. Viscosity was measured through rheological analysis. CLD was estimated from hardness readings before and after ethanol storage. CM6 (0.34 N) and CM12 (0.34 N) exhibited the lowest PSF values compared to CM0 (0.91 N). For KHN, CM6 (32.03) and CM12 (31.03) had higher values than CM0 (25.83) and were similar to CM18 (29.39) and CM24 (28.64). SS showed no significant differences among the groups. VOE indicated low vulnerability across all groups. CM12 had greater porosity compared to CM0 in BES images. CM0 had the lowest viscosity among the groups. No differences in CLD were observed among CM0, CM12, CM18, and CM24 regarding softening effects. Adding CM to Bis-GMA/TEGDMA composite resins can reduce polymerization shrinkage force and increase the initial Knoop microhardness without affecting the other properties studied. • Cholesteryl methacrylate proved to be a promising polymer for improving composites. • An endocyclic double bond can be an additional site for photochemical cycloaddition. • Its endocyclic double bond can form adducts with other monomers. • Concentrations of 6 % and 12 % of cholesteryl methacrylate promoted better performance. • Initial microhardness and polymerization shrinkage force showed improved results. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the degree of conversion (%), flexural strength (MPa), elastic modulus (GPa), compressive strength (MPa), Knoop microhardness (KHN), post-gel shrinkage (%) and prediction of ideal concentration of cholesteryl methacrylate (CM) in experimental resins. Four formulations were manipulated (F): F1, control group, (0 % CM); F2 (15 % CM); F3 (19.8 % CM) and F4 (30 % CM). Bis-GMA and CM percentages were determined using Statistica™ software. For the degree of conversion test, Raman spectroscopy was used. To testing flexural strength, elastic modulus and compressive strength, a universal testing machine was used. For the Knoop microhardness test five indentations were made in each sample. Post-gel shrinkage was determined using the strain gauge method. Statistica™ software processed all data obtained in this study. Results were submitted to one-way ANOVA and Tukey's post hoc tests (α = 0.05). Better performance was observed for F2 (15 % CM) and F3 (19,8 % CM) for degree of conversion, elastic modulus and post-gel shrinkage. For Knoop microhardness F2 (15 % CM), F3 (19,8 % CM) and F4 (30 % CM) showed higher values than F1 (0 % CM). For flexural strength F1 (0 % CM) and F3 (19,8 %) were similar and F4 showed the lowest values and for compressive strength F1 (0 % CM) showed the highest values. For mixture designs analysis data, concentrations ≤ 25 % of CM would provide better results. Addition of CM at concentrations lower than 30 % contributed to a significant increase in the degree of conversion, microhardness values, elastic modulus and reduction of post-gel shrinkage. • Cholesteryl methacrylate proved to be a promising polymer for improving composites. • An endocyclic double bond can be an additional site for photochemical cycloaddition. • Concentrations ≤ 25 % cholesteryl methacrylate enhance composite resins. • Post-gel shrinkage performed better with 15 %, 19.8 % and 30 % cholesteryl methacrylate. • Knoop microhardness was higher with 15 %, 19.8 %, and 30 % cholesteryl methacrylate. [ABSTRACT FROM AUTHOR]

Current families of reversible photochemical reactions present challenges for light‐controlled polymers of either photostationary states, which are common in photoinduced cycloaddition/cycloreversion reactions, or exclusively intramolecular bond changes, which characterize most photochromic units. In response to these challenges, here the concept of "proximal photocleavage" is presented, which combines photochemical crosslinking with a photocleavable linker, enabling a one‐time bond formation/cleavage sequence. Proximal photocleavage methacrylate monomers comprising, in series along the pendant of the methacrylate, a coumarin unit for crosslinking and either a phenacyl or ortho‐nitrobenzyl photocleavable group for decrosslinking are reported. The photophysical properties of these monomers and their statistical copolymers with methyl methacrylate are described, and wavelength selective crosslinking and de‐crosslinking of thin polymer films are demonstrated. [ABSTRACT FROM AUTHOR]

In this study, tetradecyl methacrylate-maleic anhydride-benzylidene acetone (C14MC-MA-MCA) terpolymers were synthesized via free radical polymerization and evaluated as pour point depressants (PPDs) for coal-based diesel. The findings indicate that the C14MC-MA-MCA (3:1:1) terpolymer exhibited the most effective inhibition of the solid point (SP) at 1500 ppm concentration. Specifically, it reduced the SP of coal-based diesel from − 4 to − 42 °C, marking a significant decrease of 38 °C. Furthermore, the crystallization behavior and SP reduction mechanism of C14MC-MA-MCA in coal-based diesel were investigated using viscosity analysis and polarized optical microscopy (POM). [ABSTRACT FROM AUTHOR]

Objectives: To analyze the incorporation of cardanol trimethacrylate monomer (CTMA), derived from the cashew nut shell liquid, as a substitute for Bis-GMA in acrylic resins formulations and its effect on experimental resin composites’ physicochemical and mechanical properties. Materials and methods: The intermediary cardanol epoxy was synthesized via cardanol epoxidation, followed by the synthesis of CTMA through methacrylic anhydride solvent-free esterification. Experimental resin composites were formulated with an organic matrix composed of Bis-GMA/TEGDMA (50/50 wt %) (control). CTMA was gradually added to replace different proportions of Bis-GMA: 10 wt % (CTMA-10), 20 wt % (CTMA-20), 40 wt % (CTMA-40), and 50 wt % (CTMA-50). The composites were characterized by degree of conversion, water sorption and solubility, viscosity, thermogravimetric analysis, dynamic mechanical analysis, flexural strength and elastic modulus. Data were analyzed with one-way ANOVA and Tukey’s post-hoc test (α = 0.05), except for water sorption data, which were analyzed by Kruskall-Wallis and Dunn’s method. Results: CTMA-based and control composites did not show statistically significant differences regarding degree of conversion, flexural strength and elastic modulus. CTMA reduced the viscosity and solubility compared to the Bis-GMA-based composite. The CTMA-40 and CTMA-50 exhibited significantly lower water sorption compared to the control. Also, acceptable thermal stability and viscoelastic properties were obtained for safe use in the oral cavity. Conclusions: Incorporating CTMA into composites resulted in similar chemical and mechanical properties compared to Bis-GMA-based material while reducing viscosity, water sorption and solubility. Clinical relevance: CTMA could be used as a trimethacrylate monomer replacing Bis-GMA in resin composites, thereby minimizing BPA exposure. [ABSTRACT FROM AUTHOR]

An optically accessible solid fuel scramjet was used to investigate the supersonic combustion of varying polymethyl methacrylate solid fuel grain geometries. The rear wall angle of the flameholding cavity was varied (30, 60, 75, and 90°) and an alternative geometry (flush fuel grain) containing the addition of a backwards facing step to the front of a conventional fuel grain was explored. Optical diagnostics including high-speed shadowgraph, CH* chemiluminescence, and HD video were used to analyze flammability characteristics and determine quantitative regression rates for each geometry. The optical results were supplemented by static pressure traces along the length of the combustor for the duration of a test firing. All tests were conducted with Mach 2 inlet flow into the combustor at nominal inlet conditions of 12.9 atm and 900 °C. Shadowgraph imaging for both cold flow and combusting flow was used to characterize the varying flow fields associated with their respective geometries and their core flow oscillatory frequencies were preliminarily inspected. Chemiluminescence data reveals increased heat release in the downstream constant area and expansion sections of the flush fuel grains compared to conventional geometries. This heat release appears to correlate with increased time-averaged regression rates in these regions while the varying cavity angle fuel grains demonstrate differing magnitudes of maximum regression along the rear cavity wall and onset of the constant area section. In addition to increased overall regression rates, flush geometries increase the flameholding capabilities and demonstrate self-sustained burning at lower inlet temperatures than similar geometries designed without a flush section. • This manuscript documents a study on solid fuel scramjet combustion. • Geometries which have not previously been studied were considered. • The optical access of the combustor reveals new insight on the flowfield. [ABSTRACT FROM AUTHOR]

The development of polymer carriers for systems of prolonged and controlled release of substances, particularly drugs, into the action environment is a relevant task in polymer chemistry and technology. This aims to solve the problem of reducing the effective dose of a medical drug administered into the body of a person or animal. The latest achievements in the field of creating such carriers in the form of spherical particles based on 2- hydroxyethyl methacrylate and polyvinylpyrrolidone (co)polymers are analyzed and summarized. The working principles and advantages of such systems are described. The research of the synthesis regularities, structure, properties and perspectives of application of granular hydrogels based on 2-hydroxyethyl methacrylate and its copolymers with polyvinylpyrrolidone was analyzed. The mixture of decanol and cyclohexanol as a solvent for the monomer phase is substantiated. Based on the analysis of kinetic studies, the optimal technological parameters for the suspension polymerization of 2-hydroxyethyl methacrylate with polyvinylpyrrolidone were selected, and the possibility of regulating the dispersion characteristics of copolymers via changes in the technological synthesis modes was confirmed. The results of studies on the sorption-desorption properties of copolymers concerning model substances and drugs are described. The possibility of directed regulation of sorption capacity and drug release rate through changes in copolymer composition was confirmed. Methods for increasing the sorption capacity of hydrogels for drugs are proposed. [ABSTRACT FROM AUTHOR]

A novel acrylic monomer containing a nitrofuran motif, referred to as longchain nitrofuran methacrylate (LNFMA), is reported. In comparison to the previously reported nitrofuran methacrylate (NFMA), LNFMA has a longer side chain, and when incorporated into bone cement, the resulting LNFMA bone cement exhibits improved mechanical strength. At the same concentration, NFMA-5% cement has only 21.6 ± 1.3 MPa, while LNFMA-5% cement has a compressive strength of 42.64 ± 0.94 MPa. LNFMA bone cements exhibit antimicrobial activity against Staphylococcus aureus, with LNFMA-30% cement reaching 57.38% ± 5.53%. Moreover, LNFMA cement demonstrates excellent biocompatibility both in vitro and in vivo. The results showed that LNFMA monomer had optimized mechanical strength compared with previously reported NFMA monomers, and LNFMA bone cement had good antibacterial activity and biocompatibility. [ABSTRACT FROM AUTHOR]

Countercurrent flame propagation and quenching behavior in a packed bed of spherical polymethyl methacrylate (PMMA) beads in an upward flow of pure oxygen was experimentally studied. Monosized PMMA beads of 2, 5, 8 or 10 mm in diameter (d) were packed in a vertical quartz tube of 35 mm ID to form a bed of 180 mm in height. In a typical experimental run, upon ignition from the top, a blue flame formed and propagated downwards. For d = 10, 8, or 5 mm, there existed a minimum oxygen flow rate (q) to sustain a quasi-steady state flame propagation, and the minimum q increased as d decreased from 10 to 5 mm. However, for d = 2 mm, it was not possible for the flame to propagate downwards irrespective of the q value. The apparent pyrolysis rate (mpy) of PMMA was estimated by monitoring the bed mass loss rate, from which the nominal equivalence ratio upon flame quenching was also estimated. The equivalence ratio was found to be less than unity upon flame quenching, suggesting insufficient pyrolysis gases to sustain the combustion. The heat transfer between flame and PMMA bead was analyzed theoretically, and it was revealed that the minimum mpy to sustain the quasi-steady state flame propagation inversely correlates with the PMMA particle size, and therefore a higher oxygen flow rate is required to sustain the flame propagation in a packed bed of smaller PMMA particles. [ABSTRACT FROM AUTHOR]

Lubricant‐infused organo‐gels with low surface energy solvents represent an environment‐friendly lubricating material, while the poor mechanical performance incapacitates them to harsh and intricate service conditions. To address this challenge, a simple yet highly effective strategy to prepare strong, smart, and slippery organo‐gels by glassifying the polymer network is reported. As a proof of concept, appropriate amounts of rigid solvophobic poly(phenyl methacrylate) (PPMA) units are integrated into a solvophilic poly(cyclohexyl acrylate) (PCHA) network infiltrated with lubricant. Upon forming bicontinuous phase‐separated structures, the rigid solvent‐free PPMA segments stay in glassy states, serving as a load‐bearing phase to toughen the materials effectively. Meanwhile, the soft PCHA phase maintains lubricity and extensibility by holding a substantial amount of lubricant. Owing to the synergistic effect, the gels manifest glass‐like mechanical performance with high rigidity (46.6 MPa), strength (7.7 MPa), and toughness (23.7 kJ m−2). Moreover, the materials exhibit high thermo‐sensitivity with the elastic modulus reversibly decreasing from 46.6 MPa at 20 °C to 0.23 MPa at 50 °C, endowing the gels with shape‐memory properties. Furthermore, the organo‐gels display satisfactory anti‐adhesiveness to various foreign matters. Taken together, the work represents a facile and universal strategy to reinforce organo‐gels, thereby adapting them to various applications. [ABSTRACT FROM AUTHOR]

Cranioplasty is one of the most common neurosurgical procedure performed to repair cranial defect. Many materials and fabrication technique are used to prepare cranial implant in cases where autologous bone is not available. Polymethyl Methacrylate (PMMA) is one of the most common polymer used as bone substitute. PMMA fabricated using 3D printed models have shown better fit, symmetrical shape, and restore esthetic looks of patients. The use of 3D printed implants in medical procedures has several advantages over traditional manufacturing methods. 3D printing allows for greater precision, customization, and quicker implant time. [ABSTRACT FROM AUTHOR]

Cyrene is a new biodegradable solvent, which represents a green alternative to many traditional toxic solvents for advanced polymers. Therefore, this investigation is motivated by interest in applications of Cyrene for polymer processing. The feasibility of solubilization of polymethyl methacrylate (PMMA) and polyethyl methacrylate (PEMA) in Cyrene is demonstrated. The ability to form relatively concentrated solutions of the high molecular mass polymers is an important factor for the formation of PMMA and PEMA films by a dip coating method. It was found that the polymer coatings provide corrosion protection of stainless steel in 30 g L−1 NaCl solutions. Another important finding is that the use of Cyrene facilitates the fabrication of stable suspensions of hydroxyapatite (HAp), microdiamond, and nanodiamond particles. Therefore, the problems of the dispersant selection for dispersion of chemically inert diamond and development of biocompatible dispersants are avoided using Cyrene. For the fabrication of composite films, HAp nanorods with reduced particle size are obtained using rutin as a chelating capping agent. Composite films containing HAp, microdiamond and nanodiamond in the PMMA or PEMA matrix are obtained. The composite films are promising for biomedical applications. It was found that the film morphology, composition and microstructure are influenced by the solvent–particle–polymer interactions and processing conditions. [ABSTRACT FROM AUTHOR]

Diblock copolymers of phenyl methacrylate (PMA) and butyl methacrylate (BMA) were synthesized using dual-wavelength photopolymerization with a bifunctional photoinitiator 2-(4-(2-hydroxy-2-methylpropanoyl)phenoxy)ethyl(E)-3-(1-methyl-1H-pyrrol-2-yl)acrylate (PAA-2959). [ABSTRACT FROM AUTHOR]

Ultrahigh molecular weight polymers display outstanding properties and have great application potential. However, the traditional polymerization methods have inevitable disadvantages that challenge the green synthesis of ultrahigh molecular weight polymers. The paper achieved an ultrahigh molecular weight poly (trifluoroethyl methacrylate) via a novel polymerization and discussed the mechanistic, kinetic, and experimental aspects. The combination of palladium nanoparticles with ethyl 2-bromopropionate has been identified as an exceedingly efficient system for initiating the polymerization of trifluoroethyl methacrylate. An ultrahigh molecular weight poly (trifluoroethyl methacrylate) with a number-average molecular weight up to 3.03 × 106 Da has been synthesized at a feeding molar ratio of [poly (trifluoroethyl methacrylate)]/[ethyl 2-bromopropionate]/[palladium nanoparticles] = 3.95 × 104:756:1 at 70 °C. The reaction orders concerning palladium nanoparticles, ethyl 2-bromopropionate, and poly (trifluoroethyl methacrylate) were determined to be 0.59, 0.34, and 1.38, respectively. By analyzing a series of characterizations, we verified that the polymerization of poly (trifluoroethyl methacrylate) was initiated by the ethyl 2-bromopropionate residue radicals, which were generated from the interaction between palladium nanoparticles and ethyl 2-bromopropionate. The comparatively large size of the palladium nanoparticles provided a barrier to chain-growing radicals, promoting the synthesis of ultrahigh molecular weight polymers. [ABSTRACT FROM AUTHOR]

Fractional differential viscoelastic models can describe complex material behaviours and fit experimental data well; however, the physical significance of model parameters is difficult to express. In this study, the fractional differential Maxwell, Kelvin, and Zener models were used to fit the short-term creep compliance curves of polymethyl methacrylate at different ageing times. The model fits were in good agreement with the experimental data. As the ageing time increased, the fractional differential Zener model showed a relative increase in the modulus parameter of the spring and a relative decrease in the modulus parameter reflecting the viscosity of the spring-pot, which indicated that physical ageing made the material more elastic. The relaxation time of the material increased, which indicated that the physical ageing reduced the free volume of the material, hindered the movement of molecules/segments, and increased the time required for the material to reach equilibrium. The fractional order of the model decreased, which reflected the phenomenon that physical ageing reduced the creep compliance of the material. Using the relaxation time as the time scale, the creep curves at different ageing times under the same stress level could be superimposed, naturally presenting the time–ageing time equivalence principle. [ABSTRACT FROM AUTHOR]

The development of new materials for antifreezing and anti‐icing applications is a big challenge in industry and academic area. Inspired by the antifreeze proteins, latex particles with superhydrophilic zwitterionic shells and superhydrophobic cores are synthesized by reversible addition‐fragmentation chain transfer emulsion polymerization, and the applications of the latex particles in antifreezing and anti‐icing applications are investigated. In antifreezing study, the critical aggregate temperature (CAT) of the latex particles decreases, and the separation of the melting and freezing temperature of ice increases with the particle concentration. Enzyme molecules can be cryopreserved in the particle solution, and their bioactivities are well maintained. Latex particles are casted into latex films with dynamic surfaces. Anti‐icing performances, including antifrosting properties, freezing delay time, and ice adhesion strengths, are studied; and the water‐treated latex films present stronger anti‐icing properties than other films, due to the synergistic effects of the superhydrophilic and superhydrophobic components. In addition, latex particles with zwitterionic shells and poly(n‐butyl methacrylate) cores, and latex particles with small molecular surfactant on the surfaces are synthesized. The antifreezing performances of the latex particles and anti‐icing properties of the latex films are compared. [ABSTRACT FROM AUTHOR]

Continuous flow technologies have become increasingly important for biocatalytic processes. In this study, we present the application and modelling of covalently immobilised N-acetylglucosamine 2-epimerase and N-acetylneuraminic acid lyase in packed bed reactors for the synthesis of N-acetylneuraminic acid. The immobilised enzymes were stable under continuous flow process conditions with half-life times of >28 d (epimerase immobilised on hexamethylamino methacrylate HA403/M) or 58 d (lyase immobilised on dimenthylamino methacrylate ECR8309M), suitable for continuous flow applications. Kinetic studies revealed Michaelis–Menten kinetic behaviour for both enzymes. The kinetic parameters and the inhibitions were analysed under continuous flow conditions and were integrated into a process model using Python. The model was validated by varying flow rates, the mass of immobilised enzymes and the reactor dimensions and shows a low error compared to the measured data. An error accuracy of 6% (epimerase) or 9% (lyase) was achieved. The product concentrations of the enzyme cascade at the end of the packed bed reactor can be predicted with an accuracy of 9% for the calculation of a large column (84.5 mL) or of 24% if several small columns (2.5 mL, 0.8 mL) are connected in series. The developed model has proved to be valid and will be used to optimise the process with respect to substrate concentrations, reactor dimensions and flow rate. [ABSTRACT FROM AUTHOR]

In order to analyze the effect of temperature changes on the shock initiation performance of HMX–based booster explosive, which consists of 95% HMX and 5% FPM2602 by weight, a temperature calibration test of acceptor was designed. The temperature changes in the booster at low and elevated temperatures under the constraint of steel sleeve were obtained. Based on the temperature calibration results, polymethyl methacrylate (PMMA) was selected as gap material to conduct a small scale gap test (SSGT) of HMX–based booster under different temperature conditions. The corresponding critical gap thickness was tested. Based on SSGT results at different temperatures, the shock initiation processes were simulated by adjusting parameters of ignition and growth reactive rate model. The critical gap thickness and critical initiation pressure of HMX–based booster at different temperatures were numerically predicted. By combining SSGT experimental data and simulation results, the attenuation law and fitting prediction formula of the critical initiation pressure of HMX–based booster were proposed. The mechanism of temperature effect on the shock sensitivity of HMX–based booster explosive was analyzed. The research results indicate that the critical gap thickness of HMX–based booster gradually increases with the rise in temperature, and the critical initiation pressure gradually decreases during the shock initiation process under the heating temperature conditions. In addition, the simulation results show that the heated HMX–based booster under steel constraints becomes more sensitive at high temperatures (>120 °C), while the cooled booster is more insensitive, but its critical initial pressure does not change significantly between 88 °C and 120 °C. The experimental and numerical prediction results are important for the shock initiation safety and design of an insensitive booster explosive. [ABSTRACT FROM AUTHOR]

Compatibility of polycarbonate (PC) and polymethyl methacrylate (PMMA) alloys was improved by using a transesterification catalyst (SnCl2·2H2O). Modified PC/PMMA alloys exhibit single Tg, and their initial island phase existing in the SEM were transformed into uniform surface. Besides, the transmittance of the modified alloys was increased from original 40% to 85%. Moreover, PC/PMMA alloys and PC foams with micro‐cellular and nano‐cellular structures were prepared by solid‐state CO2 foaming in the presence of transesterification catalyst. Distinctively, there are obvious nano‐cellular structures existing in the PC samples, but no related nanostructures were found in PMMA samples, after treated by same amount of catalyst and foaming process for pure PC and PMMA matrix. Furthermore, the effects of foaming temperature and segment structure on their foaming behavior were also studied. Additionally, a uniaxial stress experiment was conducted at a specific temperature to simulate the biaxial stress during the foaming process for discovering the mechanism of nanopore formation. Therefore, the concept of nano‐cellular structures will point out a direction for the development of high‐performance, heat insulation PC materials of the next generation. Highlights: Transesterification catalysts enhanced compatibility between PC and PMMA.Nanopore structures were successfully constructed in PC foams.Segment stretching was the main reason for the formation of nanopores. [ABSTRACT FROM AUTHOR]

The binder, a critical electrode component, significantly influences lithium‐ion batteries (LIB) performance, yet remains an under‐researched area. The widespread use of polyvinylidene fluoride (PVDF) as a commercial binder is challenged by its surging cost, attributed to limited production and increased demand, highlighting the necessity for alternatives. Here, we synthesize poly (trifluoroethyl methacrylate) (PTFEMA), a polymer with a molecular weight in the million range, through a straightforward radical solution polymerization method, aiming to use it as a cathode binder for LIBs. PTFEMA demonstrate good stability across the typical operating temperatures and voltages, along with robust adhesion to the current collector. Moreover, the PTFEMA outperforms PVDF in terms of electrolyte affinity and lithium‐ion conductivity, thereby achieving capacity and stability comparable to those of its PVDF counterparts. This investigation confirms the homopolymer form of PTFEMA as a compelling alternative to PVDF, representing a valuable exploration of binder technology for LIBs. [ABSTRACT FROM AUTHOR]

For the need of direct contact with the skin, electronic skins (E‐skins) should not only fulfill electric functions, but also ensure comfort during wearing, including permeability, waterproofness, and easy removal. Herein, the study has developed a self‐adhesive, detach‐on‐demand, breathable, and waterproof E‐skin (PDSC) for motion sensing and wearable comfort by electrospinning styrene‐isoprene block copolymer rubber with carbon black nanosheets as the sensing layer and liner copolymers of N, N‐dimethylacrylamide, n‐octadecyl acrylate and lauryl methacrylate as the adhesive layer. The high elasticity and microfiber network structure endow the PDSC with good sensitivity and high linearity for strain sensing. The hydrophobic and crystallizable adhesive layer ensures robust, waterproof, and detaching‐on‐demand skin adhesion. Meanwhile, the fiber structure enables the PDSC good air and water permeability. The integration of electric and wearable functions endows the PDSC with great potential for motion sensing during human activities as both the sensing and wearable performances. [ABSTRACT FROM AUTHOR]

TBRT and ATRP are orthogonal initiation chemistries used in vinyl polymerisations. Here, we present the first combination of these techniques to readily create high molecular weight branched polyester macroinitiators capable of forming star copolymers from a range of methacrylate monomers. [ABSTRACT FROM AUTHOR]

Sulfide‐based all‐solid‐state lithium batteries (ASSLBs) are potential alternatives to conventional lithium‐ion batteries for enhancing energy density and battery safety. However, the industrial sector encounters technical challenges in the fabrication of high‐mass‐loaded composite cathodes to improve the energy densities of ASSLBs. Thus, the selection of an appropriate binder and cathode active material is very important for achieving a good cycling performance of ASSLBs. In this study, wet‐processable poly(ethylene‐co‐methyl acrylate‐co‐glycidyl methacrylate) (EMG) binder and full‐concentration gradient (FCG) LiNi0.78Co0.10Mn0.12O2 (NCM) cathode active material are employed to fabricate the composite cathode with high active mass loading (21.4 mg cm−2). The EMG binder provided strong binding properties to the cathode constituents and improved the electrical conductivity of the composite cathode. The FCG NCM mitigated the morphology damages caused by volume changes in the cathode active material during cycling. Consequently, the solid‐state lithium battery with the composite cathode employing EMG binder and FCG NCM delivered a high discharge capacity of 196.6 mAh g−1 corresponding to an areal capacity of 4.21 mAh cm−2 and showed good capacity retention of 85.1% after 300 cycles at 0.2 C rate and 30 °C. [ABSTRACT FROM AUTHOR]

One method to improve the properties of covalent adaptable networks (CANs) is to reinforce them with a fraction of permanent cross‐links without sacrificing their (re)processability. Here, a simple method to synthesize poly(n‐hexyl methacrylate) (PHMA) and poly(n‐lauryl methacrylate) (PLMA) networks containing static dialkyl disulfide cross‐links (utilizing bis(2‐methacryloyl)oxyethyl disulfide, or DSDMA, as a permanent cross‐linker) and dynamic dialkylamino sulfur‐sulfur cross‐links (utilizing BiTEMPS methacrylate as a dissociative dynamic covalent cross‐linker) is presented. The robustness and (re)processability of the CANs are demonstrated, including the full recovery of cross‐link density after recycling. The authors also investigate the effect of static cross‐link content on the stress relaxation responses of the CANs with and without percolated, static cross‐links. As PHMA and PLMA have very different activation energies of their respective cooperative segmental mobilities, it is shown that the dissociative CANs without percolated, static cross‐links have activation energies of stress relaxation that are dominated by the dissociation of BiTEMPS methacrylate cross‐links rather than by the cooperative relaxations of backbone segments, i.e., the alpha relaxation. In CANs with percolated, static cross‐links, the segmental relaxation of side chains, i.e., the beta relaxation, is critical in allowing for large‐scale stress relaxation and governs their activation energies of stress relaxation. [ABSTRACT FROM AUTHOR]

Integration of hydrophobic and antibacterial functionalities into polyester‐cotton blended (PTCO) textiles has attracted more attention but remains a challenge. Here, a Janus fabric with antibacterial effect, hydrophobicity, and enhanced moisture‐permeability is fabricated using a “mist polymerization” approach. The PET fibers in the PTCO fabric are amino‐functionalized through ammonolysis reactions of PET molecules with HDA, and mist treatments of poly lauryl methacrylate (PLMA) and poly(DMC‐co‐MA) (PDM) are applied on the two side surfaces of the PTCO‐HDA fabric, respectively. The resulting Janus fabric exhibits an antibacterial rate of 99.9% against both E. coli and S. aureus, along with a hydrophobic property on its single side (PTCO‐HDA@PLMA). Additionally, the establishment of a surface‐free energy gradient across the fabric confers superior moisture‐permeability to the Janus fabric, offering advantages in preserving textile comfort. Moreover, this approach does not significantly compromise the original fabric properties, such as mechanical strength, moisture permeability, and fabric softness. The proposed method offers a straightforward and scalable strategy for textile finishing, demonstrating great potential in expanding the application scope of PTCO fabrics, and it may hold a pivotal role in diverse applications, notably encompassing home textiles, wound dressings, and high‐performance sportswear. [ABSTRACT FROM AUTHOR]

In this study, Trametes trogii‐loaded poly(2‐ hydroxyethyl methacrylate) cryogel (Tt‐PHEMA) was prepared and used as a biosorbent to remove Congo Red (CR), from aqueous solutions. The biomass and Tt‐PHEMA cryogel were characterized with scanning electron microscopy and Fourier Transform infrared spectroscopy. Macroporosity degree (%) and swelling ratio (%) of the Tt‐PHEMA cryogel were determined as 78.3% and 61.04%, respectively. The effect of loaded biomass amount, pH, initial CR concentration, temperature, and contact time were investigated detailedly. The maximum biosorption capacity of Tt‐PHEMA cryogel was 156.71 ± 1.22 mg g−1 at pH 6.0 at 45°C. Biosorption capacity was increased from 125.92 ± 1.524 mg g−1 to 156.71 ± 1.22 mg g−1 with increasing temperature from 25 to 45°C, demonstrating that the biosorption process was endothermic. The biosorption data were well fitted to the Freundlich isotherm and pseudo‐second‐order kinetic models. The negative Gibbs free energy change values showed favorable biosorption. The Tt‐PHEMA cryogel was easily regenerated with ethanol and used repeatedly five times without a significant change in the biosorption capacity. As a result, Trametes trogii‐loaded PHEMA cryogel has an application potential for CR removal from wastewater, taking advantage of interconnected macroporous structure cryogels. [ABSTRACT FROM AUTHOR]

Group transfer polymerization (GTP) plays a crucial role in polymerizing (methyl) acrylate. The utilization of cheap and easily synthesized thiourea anion (TUA) combined with pinacolborane (HBpin) undergoes controlled GTPs of methyl methacrylate (MMA), methacrylate (MA), and α‐methylenebutyrolactone (MBL) at ambient temperature. The mechanistic study reveals that the TUA′‐1 having ‐NEt2 moiety works out as a cocatalyst to assist HBpin undergoes the 1,4‐hydroboration reaction with α, β‐unsaturated acrylates to in situ generate a boron enolate (boryl ketene acetal [BKA]). Different from typical GTP, in which silyl ketene acetal (SKA) is used as an initiator, this work shows that BKA could act as an initiator with the assistance of the cocatalyst TUA′‐1 to generate the polymer. The chain end groups of the obtained polymer are characterized by MALDI‐TOF‐MS, indicating one of the chain ends features a hydride from the HBpin and another chain end has a linear or back‐biting cyclic structure. Moreover, the polymerization process is strongly supported by density functional theory (DFT) calculations. The application of BKA expands the research area of GTP reactions. The tunable and structural properties of TUA/hydroboranes significantly broaden the types of initiators in the GTP and pave a new methodology to achieve functional polymers. [ABSTRACT FROM AUTHOR]

Organic afterglow can be generated from persistent thermally activated delayed fluorescence (pTADF) or organic ultralong room temperature phosphorescence (OURTP), but the pTADF plus OURTP type organic afterglow is challenging to achieve, especially for the color‐tunable and high‐temperature ones. Herein, an accessible strategy toward such dual‐mode afterglow is presented by doping the indolo[3,2‐b]carbazole (ICZ‐p1) into polymethyl methacrylate (PMMA). The resulting films exhibit photo‐activated afterglow with two persistent emission peaks of ca. 435 and 497 nm. Impressively, their longest lifetimes respectively reach to 2.28 and 2.47 s at 298 K, along with 0.32 and 0.42 s at 360 K, enabling the afterglow at room and high temperature. Experimental and theoretical results reveal that the photo‐activated afterglow is associated with the elimination of molecular O2 inside film and composed by the pTADF with multi‐resonance (MR) effect and OURTP. By altering the temperature from 77 to 358 K, the color‐tunable afterglows of green and blue are harvested at such temperature ranges. Benefiting from the multi‐resonance thermally activated delayed fluorescence (MRTADF) characteristics, this emitter can release narrow‐band electroluminescence. Consequently, the results obtained here may offer important references for chasing MRTADF plus OURTP‐type dual‐mode organic afterglow showing color‐tunable and high‐temperature features. [ABSTRACT FROM AUTHOR]

Dual‐ion batteries (DIBs) represent a promising alternative for lithium ion batteries (LIBs) for various niche applications. DIBs with polymer‐based active materials, here poly(2,2,6,6‐tetramethylpiperidinyl‐N‐oxyl methacrylate) (PTMA), are of particular interest for high power applications, though they require appropriate electrolyte formulations. As the anion mobility plays a crucial role in transport kinetics, Li salts are varied using the well‐dissociating solvent γ‐butyrolactone (GBL). Lithium difluoro(oxalate)borate (LiDFOB) and lithium bis(oxalate)borate (LiBOB) improve cycle life in PTMA||Li metal cells compared to other Li salts and a LiPF6‐ and carbonate‐based reference electrolyte, even at specific currents of 1.0 A g−1 (≈10C), whereas LiDFOB reveals a superior rate performance, i. e. ≈90 % capacity even at 5.0 A g−1 (≈50C). This is attributed to faster charge‐transfer/mass transport, enhanced pseudo‐capacitive contributions during the de‐/insertion of the anions into the PTMA electrode and to lower overpotentials at the Li metal electrode. [ABSTRACT FROM AUTHOR]

Ionic conductive hydrogels (ICHs) have recently gained prominence in biosensing, indicating their potential to redefine future biomedical applications. However, the integration of these hydrogels into sensor technologies and their long‐term efficacy in practical applications pose substantial challenges, including a synergy of features, such as mechanical adaptability, conductive sensitivity, self‐adhesion, self‐regeneration, and microbial resistance. To address these challenges, this study introduces a novel hydrogel system using an imidazolium salt with a ureido backbone (UL) as the primary monomer. Fabricated via a straightforward one‐pot copolymerization process that includes betaine sulfonate methacrylate (SBMA) and acrylamide (AM), the hydrogel demonstrates multifunctional properties. The innovation of this hydrogel is attributed to its robust mechanical attributes, outstanding strain responsiveness, effective water retention, and advanced self‐regenerative and healing capabilities, which collectively lead to its superior performance in various applications. Moreover, this hydrogel exhibited broad‐spectrum antibacterial activity. Its potential for biomechanical monitoring, especially in tandem with contact and noncontact electrocardiogram (ECG) devices, represents a noteworthy advancement in precise real‐time cardiac monitoring in clinical environments. In addition, the conductive properties of the hydrogel make it an ideal substrate for electrophoretic patches aimed at treating infected wounds and consequently enhancing the healing process. [ABSTRACT FROM AUTHOR]

Durable functionalization on polypropylene (PP) surfaces is always a key problem to besolved. Coatings with low surface energy peel off easily especially under extreme conditions, owing to their weak adhesion. In this paper, side groups of both polyhedral oligomeric silsesquioxane (POSS) and alkane are grafted to polypentafluorophenyl methacrylate (PFP), and then PP blends with these side‐group modified PFP are obtained through a melt‐blending process. It is found that POSS can result in surface segregation and provide hydrophobicity in blends. Microfibers are formed because of the orientation effect during the tensile testing, which furtherly promotes mechanical strength. Significantly, alkaneside‐groups can be entangled with PP segments, which brings about cross linking. Therefore, with crosslinking and synchronous orientation of POSS, the elongation at the break of blends is greatly increased up to 974%. The final blend demonstrates quite durable hydrophobicity under many extreme conditions, such as repeated tape peeling, ultrasonic washing, strong friction, and soaking in strong acid (pH = 1), strong alkali (pH = 14) and alcohol. The heat and UV resistance of the blend are also obviously improved. This study will develop anovel and facile strategy to endow PP with durable hydrophobicity as well as greatly enhanced mechanical properties. [ABSTRACT FROM AUTHOR]

Introduction This paper examines the use of local antibiotic therapy in one-stage septic revision surgery for late periprosthetic joint infections (PJIs). This case study suggests that morselized bone allografts impregnated with antibiotics in powder form are a preferable alternative to polymethyl methacrylate (PMMA) because they can generate higher local antibiotic concentrations. Current research also recommends using vancomycin and aminoglycosides as the preferred choice of antibiotics, as they may have low diffusion in tissues when administered intravenously, but are effective when administered locally. The article emphasizes the importance of achieving high local antibiotic concentrations to eradicate bacterial biofilms and provides guidelines for the preparation of bone allografts. Case report The paper assesses the case study of a 68-year-old male patient who underwent two-stage total revision surgery for a late septic failure of the endoprosthesis (approximatively one year after implantation). The first stage involved removing the implant, debridement, lavage, and setting a fixed spacer manually made from polymethyl methacrylate impregnated with 4 g of vancomycin. The second stage of revision surgery utilized a morselized bone allograft impregnated with 4 g of vancomycin as a means of local antibiotic therapy and bone defect coverage. Systemic levels of vancomycin were measured at 4, 8, 12 and 24 hours respectively after surgery. During this period, no systemic vancomycin was administered. After the second stage was carried out and the testing was carried out, systemic vancomycin therapy was initiated and the plasma levels of the drug were assessed and subsequently therapeutic doses were adjusted. Conclusions Vancomycin loaded bone allograft achieved higher systemic concentrations that its polymethyl methacrylate counterpart, when being manually loaded with the same amount of antibiotic. Nonetheless, the levels were well below nephrotoxic levels, indicating that this may be a valuable tool for local means of antibiotic therapy in selected patients that could not endure such a systemic therapeutic regiment. For septic revisions, antibiotic loaded bone allograft holds a valuable place in the surgical arsenal of local antimicrobial treatment, by far exceeding that of the polymethyl methacrylate. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is one of promising biocompatible and biodegradable polyester. Poly(2-hydroxyethyl methacrylate) (PHEMA) is a polymer with good hydrophilicity. The hydrophilic PHEMA may improve PLA's amphiphilic properties. Hence, directly starting from hydroxyethyl methacrylate (HEMA), lactic acid (LA), maleic anhydride (MAH) and 2,2'-azobis(2-methyl-propionitrile) (AIBN), a series of new amphiphilic copolymers PLA20MHn were obtained through direct melt polycondensation (DMP) and subsequent free radical polymerization (FRP) in one pot. The results show that PLA20MHn can self-assemble in aqueous solution to form stable spherical micelles and dissolve hydrophobic pyrene molecules. What's more, The CMC value can be adjusted by the polymerization ratio. Therefore, this method is expected to further realize the encapsulation and controlled release of hydrophobic drug molecules for systemic circulation in vivo. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective The aim of this study was to assess and compare the impact of bulk-fill flowable resin composite liners (BFFL) on the 2-year clinical performance of bulk-fill ormocer (BORC) in comparison to methacrylate-based resin composites (BMRC) in Class II cavities. Materials and Methods Thirty participants, each aged between 18 and 30 years, were included in the study, each presenting four class II cavities. A total of 120 restorations were placed, with participants randomly assigned to one of four restorative systems through a blind drawing: Admira Fusion X-Tra (AFX) alone, AFX after lining with Admira Fusion Xtra-Base (AFB), X-Tra Fill (XF) for complete cavity filling, and XF after lining with Xtra-Base (XB). The universal adhesive system (Futura U bond Voco, Germany) was consistently applied for all restoration techniques using selective enamel etching. A single operator, following the manufacturer's instructions for each material, performed all restorations, and finishing/polishing occurred immediately after placement. Clinical evaluation, based on World Dental Federation (FDI) criteria, was conducted by two blinded examiners at baseline (7 days) and at 6, 12, and 24 months postoperatively. Results The chi-squared test was used to compare the four applied restorative systems within each follow-up period, while the marginal homogeneity test was employed to assess changes over time. No statistically significant differences were observed among the four restorative systems at any evaluation period. Conclusions After 2 years, the clinical performance of BFFL or complete bulk-fill technique remained similar, regardless of the material composition. [ABSTRACT FROM AUTHOR]

This study illustrates the deposition of thermo responsive p(N-isopropyl acrylamidehydroxypropyl methacrylate) p(NIPAAm-HPMA) copolymer thin films by initiated chemical vapor deposition (iCVD) method using tert-butyl peroxide (TBPO) as the initiator. Copolymers were deposited at three different HPMA flow rates and the effects of NIPAAm/HPMA flow rate ratio on the deposition rate, structure and responsive properties of the as-deposited films were investigated. The highest deposition rate of 50 nm/min was observed for the copolymer deposited using lowest NIPAAm/HPMA monomer ratio studied. The deposition rate showed a significant increase with decreasing NIPAAm/HPMA flow ratio. Results of FTIR and XPS spectroscopy analyses revealed a significant preservation of structural retention in iCVD p(NIPAAm-HPMA) thermo-responsive films. Lower critical solution temperatures (LCST) of p(NIPAAm-HPMA) films were determined by carrying out a temperature-dependent contact angle analysis. Accordingly, it was shown that LCST was varied between 19 and 23 oC, which was observed to be dependent on the NIPAAm/HPMA monomer ratio. That LCST range is considerably below the literature-reported values for pNIPAAM, which makes the as-deposited copolymer suitable for applications that require thermos-responsive properties at lower temperatures. [ABSTRACT FROM AUTHOR]

Copyright of China Rubber Industry is the property of Editorial Office of China Rubber Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Self-cleaning treatment is of vital importance for the practical application of functional cotton fabrics. However, developing highly efficient, eco-friendly, and durable hydrophobic and oleophobic treatment agents still remains a great challenge. Herein, inspired by the design of the inorganic–organic nanonetwork, we successfully synthesized a novel core–shell structured emulsion of nano-SiO2/fluorine-silicon polyacrylate through semi-continuous emulsion polymerization. The introduction of long-chain alkyl methacrylate octadecyl ester within the shell phase results in a more organized arrangement of fluorine atoms on the surface of cotton fabrics, leading to a rapid reduction in the surface free energy of latex film. The sample is optimized with 20 wt% dodecafluoroheptyl methacrylate and 1 wt% SiO2. The nanoengineered emulsion exhibits strong adhesion and effectively transforms the hydrophilic cotton fabrics into hydrophobic (143.2°) and oleophobic (121.6°) materials. Besides, the self-cleaning characteristic can withstand 25 laundering cycles and 800 abrasion cycles with enhanced robustness. This work opens up a pathway to develop effective, green but long-lasting amphiphobic agents for functional fabrics and sustainable textiles. [ABSTRACT FROM AUTHOR]

This document discusses the development and application of advanced sorbents for the separation of metal ions. Traditional sorbents face limitations in terms of selectivity, efficiency, and cost-effectiveness, but advanced sorbents made from new and modified materials show promise in overcoming these challenges. These sorbents have high surface areas, tunable pore structures, and functionalized surfaces, which improve their metal-ion adsorption capacity, selectivity, and kinetics. The document highlights various applications for these sorbents, including water treatment, hydrometallurgy, environmental remediation, and analytical chemistry. The articles in this special issue explore different types of sorbents and their effectiveness in metal-ion separation, providing insights into their synthesis, adsorption mechanisms, and process optimization. Future studies should focus on scaling up these sorbent applications, improving their selectivity and efficiency, and incorporating them into comprehensive process systems to meet the increasing demands for metals and environmentally friendly waste management solutions. [Extracted from the article]

The fracture response of geologic materials is of interest for applications, including geothermal energy harnessing and containment of underground explosions. To better understand the explosively induced fracture response of geomaterials, polymethyl methacrylate (PMMA) was used as a transparent rock surrogate to allow imaging of internal shock propagation and fracture growth processes. Experiments were conducted using high-speed shadowgraphy and photon Doppler velocimetry (PDV), which were compared to numerical simulations. Experiments measured fractures produced in 304.8 mm × 304.8 mm × 304.8 mm PMMA cubes with two simultaneously initiated detonators. The cubes were subjected to varying amounts and directions of externally applied uniaxial stresses, including no stress, 2 MPa stress, and 20 MPa stress. The fracture radius as a function of time was extracted from the high-speed videos. Post-test images of the PMMA cubes aided in the determination of three-dimensional effects not directly imaged by the cameras. The surface velocity history and the shock response captured in PDV and the high-speed videos were compared to the simulated explosive-induced shock response. The simulation results indicate that the shock drives the fracture for the first 20 μ s corresponding to a fracture radius of approximately 15 mm in the experiments. The gas-driven fracture extent was estimated analytically using an equilibrium stress distribution calculated after the shock wave propagation through the sample. Reduction in the gas pressure due to the leakage of the explosive products through the crack as a function of time was accounted for. The estimated fracture lengths were in agreement with the experimentally observed fracture lengths. [ABSTRACT FROM AUTHOR]