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The structure used in this study is as follows: substrate/PMMA/ZnS/Ag/MoO3/NPB/Alq3/LiF/Al. Here, PMMA serves as the surface flattening layer, ZnS/Ag/MoO3 as the anode, NPB as the hole injection layer, Alq3 as the emitting layer, LiF as the electron injection layer, and aluminum as the cathode. The properties of the devices with different substrates were investigated using P4 and glass, developed in the laboratory, as well as commercially available PET. After film formation, P4 creates holes on the surface. The light field distribution of the device was calculated at wavelengths of 480 nm, 550 nm, and 620 nm using optical simulation. It was found that this microstructure contributes to light extraction. The maximum brightness, external quantum efficiency, and current efficiency of the device at a P4 thickness of 2.6 μm were 72,500 cd/m2, 1.69%, and 5.68 cd/A, respectively. However, the maximum brightness of the same structure with PET (130 μm) was 9500 cd/m2. The microstructure of the P4 substrate was found to contribute to the excellent device performance through analysis of the AFM surface morphology, film resistance, and optical simulation results. The holes formed by the P4 substrate were created solely by spin-coating the material and then placing it on a heating plate to dry, without any special processing. To confirm the reproducibility of the naturally formed holes, devices were fabricated again with three different emitting layer thicknesses. The maximum brightness, external quantum efficiency, and current efficiency of the device at an Alq3 thickness of 55 nm were 93,400 cd/m2, 1.7%, and 5.6 cd/A, respectively. [ABSTRACT FROM AUTHOR]

Hierarchical self-assembly is efficient in transferring functionality from small to large scales. Polymer nanoparticles with regularity are highly desirable because they are ideal units of hierarchical self-assembly. Herein, we proposed a crosslinking strategy for generating nanoparticles from ABC linear triblock copolymers and conducted a computational study on the self-assembly of the nanoparticles. The effect of nanoparticle symmetry on aggregation behaviors was examined. We found that the symmetric patchy nanoparticles can form various low-curvature aggregates tuned by the crosslinking numbers and A/C block lengths. Increasing the asymmetry of patchy nanoparticles causes the increased curvature of assemblies, forming well-defined structures such as loops, vesicles, and wavy ribbons. Furthermore, the self-assembly kinetics reveals a step-growth nature, resembling the step polymerization for one-dimensional growth. The work demonstrates that ABC-type polymeric nanoparticles are versatile units for building hierarchical assemblies, considerably enriching the self-assembly strategies.

Heart failure (HF) is one of the diseases that lead to high mortality of patients. Finding natural compounds with cardioprotective properties and identifying their action mechanisms is of great importance. In this research, the effect of propolis and triblock copolymer nano-vesicles loaded with propolis were studied in Wistar rats HF model. After preparing propolis and Polylactide-block-poly (ethylene glycol)-block-polylactide (PLA-PEG-PLA) loaded with propolis using thin film hydration method, nanoparticles were identified using transmission electron microcopy (TEM) and Zetasizer techniques. Induction of HF in animals was done with 85 mg/kg isoproterenol for 2 consecutive days and 200 mg/kg/day of both propolis and PLA-PEG-PLA nano-vesicle loaded with propolis were administered to rats by oral gavage one week before HF induction and one week after that. On the last day, echocardiography parameters were measured and then, with blood sampling and plasma preparation, the levels of biochemical parameters such as B-type natriuretic peptide (BNP), Galectin-3, interleukin 1β (IL-1β), interleukin 6 (IL-6), interleukin 10 (IL-10), interleukin (IL-17), reduced AMP-activated protein kinase (AMPK) and silent information regulator (SIRT1) were measured using Enzyme-linked immunosorbent assay (ELISA) technique. Both propolis and PLA-PEG-PLA nano-vesicle loaded with propolis led to improvement of echocardiographic parameters in HF rats. Also, the administration of these two compounds decreased the expression of inflammatory cytokines IL-1, IL-6 and IL-17 and increased the expression of IL-10 in HF rats. The levels of SIRT1 and AMPK in HF rats receiving propolis and PEG-PLA loaded with propolis were upregulated compared to HF control ones. In conclusion, it can be indicated that propolis and PEG-PLA loaded with propolis have cardio protection effects through decreasing inflammation and activation of SIRT1-AMPK axis.

This study investigates the effect of an inert salt (NaCl) on the equilibrium interfacial tension and dilatational modulus of Pluronic F-68 copolymer, a triblock copolymer consisting of two terminal blocks of poly(ethylene oxide) and a less hydrophilic central block of poly(propylene oxide). Interfacial tension measurements were carried out using a surface force balance and a drop shape tensiometer, while rheological measurements were carried out in two different frequency ranges. This involved the use of the oscillatory barrier/droplet method and electrocapillary wave measurements, complemented by an appropriate theoretical framework. This work aimed to elucidate the influence of NaCl on the interfacial behavior of Gibbs monolayers of Pluronic F-68. In addition, this study highlights some of the technical and theoretical limitations associated with obtaining reliable dilatational rheological data at high frequencies (

Microwave irradiation is used in this study to synthesize poly (acrylamide-co-2-hydroxyethyl methacrylate)/chitosan (P(AM-co-HEMA)/chitosan) semi-IPN hydrogels, which are synthesized using one-pot polymerization techniques with ammonium persulfate (APS) as an initiator. The first step was to synthesize a (P(AM-co-HEMA) network in a chitosan aqueous solution, which formed a semi-IPN structure. Nanocomposite membranes of P(AM-co-HEMA)/chitosan membranes with varying Zinc oxide concentrations i.e. 2.5, 5, and 10 wt. % gravimetrically were tested for gas permeability measurements of pure oxygen gas at feed pressures ranging from 1 to 20 kg/cm2. The permeability of the membranes to oxygen ranged from 0.0963 to 0.2634 Barrer for the pristine Poly (Acrylamide-co-2-Hydroxyethyl Methacrylate)/Chitosan Semi-IPN membrane, and 5 and 10 wt. % ZnO loaded blend membranes showed good resistance and zero permeability at feed pressures of 1–5 kg/cm2 and 0.0341 to 0.0364 Barrer for 10 wt. % ZnO loaded blend membranes by increasing the feed pressures at the feed chamber. The nanocomposite membranes were tested for antimicrobial properties and found to be a more effective antimicrobial material. The results of the soil burial tests show that the prepared membranes are biodegradable. Mechanical strength is exceptional under normal conditions.

By introducing thiourea and ether groups into MQ silicone resin polymer via free radical polymerization, a polyether-thiourea-siloxane (PTS) copolymer was synthesized. The characterization of the synthesized copolymer indicated the occurrence of H-bonding interactions and a narrow molecular weight polydispersity index. Antifouling coatings were produced by incorporating the synthesized copolymer and phenylmethylsilicone oil (PSO). The addition of a minute amount of copolymer enhanced the hydrophobicity of the coating by increasing its surface roughness. However, excessive addition of copolymer resulted in a significant deterioration of the coating surface smoothness. The copolymer improved the mechanical properties of the coating, but excessive addition decreased the crosslinking density and weakened the mechanical performance. With increasing copolymer addition, the leaching of PSO was significantly improved due to the change in the storage form of PSO in the coating caused by the copolymer. Based on the H-bonding interaction of the copolymer, the adhesion strength between the coating and the substrate was significantly improved. However, excessive addition of copolymer did not infinitely enhance the adhesion strength. The antifouling performance demonstrated that an appropriate amount of copolymer could obtain adequate PSO leaching efficiency, thereby effectively enhancing the antifouling performance of the coating. In this study, the prepared coating P12 (12 g of PTS in 100 g of PDMS) showed the most effective antifouling performance. [ABSTRACT FROM AUTHOR]

This study presents an experimental investigation on thermoplastic carbon fiber composite based on PMMA resin interleaved with Polyamide electrospun nanofiber veils. In particular, the effect of improving the interfacial adhesion of the resin to nanofiber and carbon fiber on the fracture behavior of the laminates and the corresponding fracture mechanism was studied by using different molar concentrations of functional monomer hydroxyethyl acrylamide (HEAA) for copolymerization with methyl methacrylate. The effectiveness of the nanoreinforce has been addressed by Mode-Ⅰ and Mode-Ⅱ tests. The results showed that the fracture toughness of Mode-Ⅰ decreased firstly and then increased with an increase in HEAA feed with 0–5 mol% due to the change of crack tip path accompanied by the bridging mechanism shifting, the best performance was founded in 5 mol% HEAA-copolymerized thermoplastic carbon fiber composites (CFRTP) samples (17.6% for initiation and 28% for propagation); whereas a characteristic of increasing firstly and then decreasing performed under Mode-Ⅱ loading due to the formation of multilayer microcrack in nano-toughing matrix layer, the 3 mol% HEAA-copolymerized CFRTP samples exhibited good improvement (137% for initiation and 147% for propagation). [ABSTRACT FROM AUTHOR]

In the process of using lubricating oil, it is inevitable that bubbles will be produced, which can not only accelerate the oil's oxidation and shorten the oil change cycle but also reduce its fluidity and lubricity, aggravate the wear of mechanical parts and produce an air lock that interrupts the oil pump supply and causes an oil shortage accident. This paper mainly and comprehensively discusses the foaming process and its harm, the defoaming mechanism and defoaming method of lubricating oil, more specifically, the synthesis, application, advantages, disadvantages and current situation of three kinds of chemical defoaming agents, namely silicone defoaming agent, non-silicone defoaming agent and compound defoaming agent. Finally, the paper looks forward to the future development of special defoaming agents for lubricating oil. [ABSTRACT FROM AUTHOR]

To effectively control CaCO3 scaling in oilfield-produced water, terpolymer scale inhibitor P(IA-AA-SHP) was synthesized by aqueous solution polymerization using itaconic acid (IA), acrylic acid (AA) and sodium hypophosphite (SHP) as raw materials and ammonium persulfate as an initiator. The optimal monomer ratio, initiator dosage, reaction temperature, and time for copolymer synthesis were determined by the controlled variable method. According to the static scale inhibition performance test method in the oilfield, the copolymer dose reached 95.8% inhibition efficiency of CaCO3 at 30 mg L−1. A study of the inhibitory efficiency of copolymer on the CaCO3 scale at different Ca2+ concentrations, CO32− concentrations, and temperatures was also carried out, and the excellent scale inhibition efficiency was maintained despite a change in the water quality conditions. The structure of copolymer P(IA-AA-SHP) was characterized by FTIR, UV, 1H-NMR, and 13C-NMR. Since the molecular weight (Mw) has a great influence on the scale inhibition performance, the relationship between the molecular weight of the polymer and the scale inhibition performance was discussed using gel permeation chromatography (GPC) to detect the molecular weight of the product. The copolymers were shown to have excellent thermal stability using thermogravimetric (TGA) analysis. The effect of copolymers on the morphological structure of CaCO3 crystals was analyzed by SEM and XRD, and the mechanism of scale inhibition was discussed. [ABSTRACT FROM AUTHOR]

Objective The aim is to solve the problem that the natural gas hydrate formed in the process of gathering and production of natural gas blocks the pipeline, wellbore and porous media in the formation. Methods A kinetic hydrate inhibitor NADN was synthesized with N-vinyl pyrrolidone (NVP), allyl polyethylene glycol (APEG-1000), dimethyl diallyl ammonium chloride (DMDAAC) and N-hydroxymethyl acrylamide (N-HAM). The optimum synthesis conditions were obtained by single factor experiment. Results The molar ratio of n (NVP), n (DMDAAC), n (N-HAM), n (APEG-1000) was 1∶2∶2∶0.3, reaction temperature was 60 ℃, reaction time was 6 h, and monomer concentration was 35%, the mass of initiator accounts for 0.3% of the total mass of monomer. The structure was consistent with the original design structure by FIRT and ¹H NMR. Conclusions Experiment results showed that when the dosage of inhibitor reaches 1.05%, it showed excellent inhibition effect under the ambient temperature of-18 ℃. The freezing temperature of hydrate could be as low as-7.5 ℃. [ABSTRACT FROM AUTHOR]

Four siloxane benzoxazines containing different rigid segments were successfully synthesized and characterized herein, including a benzene ring, a biphenyl, a naphthalene ring, and a diphenyl sulfone group. Different rigid segments had different effects on polymer properties. The introduction of the naphthalene ring and sulfone group considerably reduced the curing temperature of benzoxazine. Although the benzoxazine with the naphthalene ring exhibited low heat resistance, all the four samples showed a high char yield at 800°C under nitrogen atmosphere. In addition, during copolymerization with AG-80 epoxy, the introduction of epoxy promoted the curing of the benzoxazines containing the naphthalene ring and sulfone group. The heat resistance of all copolymers was considerably improved, especially for the copolymer containing the naphthalene ring, whose 5% thermal weight loss temperature (T d5) increased from 248°C to 321°C under nitrogen atmosphere. The copolymer containing the biphenyl structure had the highest glass transition temperature, reaching 259.1°C. Copolymerization with epoxy also considerably improved the tensile strength and elongation at break of the copolymers, which were much higher than those of traditional bisphenol A-aniline based benzoxazine (BA-a). Compared with the neat benzoxazine prepared using siloxane and bisphenol A, the developed copolymers also had better tensile properties, and the copolymer containing the sulfone group showed the greatest improvement (from 49 to 69 MPa, from 3.1% to 9.12%). [ABSTRACT FROM AUTHOR]

Previous studies on linear epoxy (bisphenol A epoxy) resin/benzoxazine composites showed that with the addition of epoxy (EP) resin, the resulting copolymers exhibited an increased glass transition temperature (T g) (T g reached a maximum value at a specific content), improved flexural strength, lower heat resistance, and reduced tensile strength. Herein, branched EP resin (AG-80)/benzoxazine copolymers featuring novolac (N-box) and siloxane (Si-box) chains were prepared without any external curing agent. In both systems, the EP resin endowed the copolymers with an increased crosslinking density; however, T g continued to increase with increasing EP content. In addition, the heat resistance of the copolymers gradually enhanced. Different types of benzoxazines have various effects on the properties of copolymers. In terms of mechanical properties, AG-80/N-box copolymers exhibited brittle fracture characteristics; with increasing EP content, the flexural strength of the copolymer decreased while the tensile strength increased. AG-80/Si-box copolymers exhibited ductile fracture characteristics, with gradual increases in flexural and tensile strengths. Furthermore, with increasing EP content, the molecular chain migration ability and network homogeneity of the AG-80/N-box copolymers decreased gradually. Alternatively, in the case of the AG-80/Si-box copolymers, the molecular chain migration ability remained unchanged and network homogeneity improved. Hence, the developed copolymers can be used as resin matrices for the fabrication of advanced composites. [ABSTRACT FROM AUTHOR]

Shape memory blends of polycaprolactone/thermoplastic polyurethane (PCL/TPU) were prepared by in situ ring‐opening polymerization (ROP) of ε‐caprolactone (CL) and thermoplastic polyurethane (TPU). Fourier infrared spectrometer and 1H‐NMR were used to characterize the chemical structure of PCL/TPU copolymers. The results show that TPU has been involved in the ROP of CL, leading to the formation of copolymers with homogeneous morphologies. Besides, pure PCL and all the blends exhibit an excellent shape fixation ratio of 100%, due to their high crystallinity. When a small amount of TPU is introduced, the crystallinity of PCL decreases, and as a result, the shape recovery ratio of the copolymer is enhanced compared with pure PCL. However, with the increased loading of TPU, the content of PCL as the reversible phase decreases and the storage modulus of the PCL/TPU blend declines, so the driving force for the blends to return from the temporary shape to the initial shape becomes smaller, leading to a decrease in the shape recovery ratio. Notably, when the amount of TPU is only 5%, the shape recovery ratio of the blend could reach 83.3%, which is 26% higher than that of pure PCL, and meanwhile, the tensile strength of the blend decreases slightly. This study provides a new strategy for the design of shape‐memory materials with high shape‐memory properties. [ABSTRACT FROM AUTHOR]

A new polyfunctional optically transparent copolymer based on 2-methoxycarbonyl paracyclopropyl styrene (MCCPS) and glycidyl methacrylate (GMA) has been synthesized. The compositions and structures have been established, and the copolymerization parameters of the synthesized copolymer have been found. The values of copolymerization constants were calculated according to the Fineman–Ross equation (r1 = 1.36, r2 = 0.30) and Q–e parameters according to Alfrey–Price (Q1 = 2.573, e1 = –0.846). It was found that 2-methoxycarbonyl paracyclopropyl styrene is a more active monomer in radical copolymerization than GMA. The parameters of the microstructure of the copolymer have been determined. Compared to polystyrene, the resulting copolymer has a higher refractive index ( = 1.5820). The degree of light transmission of the copolymer was established, which is 88–90%. Depending on the composition of the optically transparent copolymer, the rate of change in the light transmission index was studied. It is shown that the synthesized copolymer surpasses polystyrene and GMA in terms of the main performance indicators and exhibits high optical transparency, which makes it possible to use it in the manufacture of parts for optical devices. [ABSTRACT FROM AUTHOR]

Cyclodextrins (CDs) are one of the most extensively studied cyclic-oligosaccharides due to their low toxicity, good biodegradability and biocompatibility, facile chemical modification, and unique inclusion capacity. However, problems such as poor pharmacokinetics, plasma membrane disruption, hemolytic effects and a lack of target specificity still exist for their applications as drug carriers. Recently, polymers have been introduced into CDs to combine the advantages of both biomaterials for the superior delivery of anticancer agents in cancer treatment. In this review, we summarize four types of CD-based polymeric carriers for the delivery of chemotherapeutics or gene agents for cancer therapy. These CD-based polymers were classified based on their structural properties. Most of the CD-based polymers were amphiphilic with the introduction of hydrophobic/hydrophilic segments and were able to form nanoassemblies. Anticancer drugs could be included in the cavity of CDs, encapsulated in the nanoparticles or conjugated on the CD-based polymers. In addition, the unique structures of CDs enable the functionalization of targeting agents and stimuli-responsive materials to realize the targeting and precise release of anticancer agents. In summary, CD-based polymers are attractive carriers for anticancer agents. [ABSTRACT FROM AUTHOR]

Four samples, including homopolymerized PP (PP-1), random impact copolymerized PP (PP-2), random impact copolymerized PP of ethylene-propylene (PP-3), and random impact copolymerized PP of ethylene-propylene-butylene (PP-4), which were prepared by 75 KG Spheripol process pilot plant using ZN104M as catalyst, were adopted to study the structure and performance, i.e., the influence of the different polypropylene molecular chain structures on the crystallization behavior of random impact copolymer polypropylene, and the changes in mechanical and optical performance due to the different aggregation structures of random impact copolymer polypropylene, and following results were achieved. Firstly, when ethylene-propylene rubber (EPR) and copolymerization monomers of ethylene and butylene were added in turn, the regularity of PP molecular chains decreased in different degree with the order of PP-1 > PP-2 > PP-3 > PP-4, and which further led to the same pattern for the crystallization peak temperature and the crystallinity. Secondly, half-crystallization time (T1/2) of the same cooling rate and the crystallization activation energy increased with the addition of EPR, ethylene and butylene. Crystallization activation energies were calculated to be 12.05 kJ mol−1, 12.09 kJ mol−1, 12.38 kJ mol−1 and 12.64 kJ mol−1 for PP-1, PP-2, PP-3 and PP-4, respectively. Last but the most importantly, the addition of EPR, ethylene and butylene would enhance the impact strength, but decrease the transmittance, whereas the haze changed little. Based on the theory between structure and performance, the reason that caused above results were analyzed. This work provided some guidance for the development of high-performance polypropylene used in identical fields. [ABSTRACT FROM AUTHOR]

The information of second and third distances within a graph is given by Zagreb and Wiener polarity indices. Both of these indices are important for QSPR applications. In this paper, we have studied leap Zagreb Index, leap Zagreb co-index and Wiener Polarity Index of Dox-loaded micelle containing PEG-PAsp block copolymer with chemically conjugated Dox denoted by sp [ n ]. We also computed the leap Zagreb coincides for sp [ n ]. [ABSTRACT FROM AUTHOR]

Fabrication and characterization of hybrid nanomats containing quantum dots can play a prominent role in the development of advanced biosensors and bio-based semiconductors. Owing to their size-dependent properties and controlled nanostructures, quantum dots (QDs) exhibit distinct optical and electronic characteristics. However, QDs include heavy metals and often require stabilizing agents which are toxic for biological applications. Here, to mitigate the use of toxic ligands, cadmium selenide quantum dots (CdSe QDs) were synthesized in situ with polyvinylpyrrolidone (PVP) at room temperature. The addition of PVP polymer provided size regulation, stability, and control over size distribution of CdSe QDs. The characterization of the optical properties of the CdSe QDs was performed using fluorescence and ultraviolet–visible (UV-Vis) spectroscopy. CdSe QDs exhibited a typical absorbance peak at 280 nm and a photoluminescence emission peak at 580 nm. Transmission electron microscopy (TEM) micrographs demonstrated that CdSe QDs having an average size of 6 ± 4 nm were obtained via wet chemistry method. CdSe QDs were immobilized in a blend of PVP and poly(L-lactide-co-ε-caprolactone) (PL-b-CL) copolymer that was electrospun to produce nanofibers. Scanning electron microscopy (SEM), thermal analyses and attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) were used to characterize properties of fabricated nanofibers. Both pristine and hybrid nanofibers possessed cylindrical geometry and rough surface features, facilitating increased surface area. Infrared absorption spectra showed a slight shift in absorbance peaks due to interaction of PVP-coated CdSe QDs and nanofiber matrix. The presence of CdSe QDs influenced the fiber diameter and their thermal stability. Further, in vitro biological analyses of hybrid nanofibers showed promising antibacterial effect and decline in cancer cell viability. This study offers a simple approach to obtain hybrid nanomats immobilized with size-controlled PVP-coated CdSe QDs, which have potential applications as biosensors and antibacterial and anticancer cell agents. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI) is a significant cause of morbidity and mortality worldwide. Varied mechanisms of injury contribute to the heterogeneity of this patient population as demonstrated by the multiple published grading scales and diverse required criteria leading to diagnoses from mild to severe. TBI pathophysiology is classically separated into a primary injury that is characterized by local tissue destruction as a result of the initial blow, followed by a secondary phase of injury constituted by a score of incompletely understood cellular processes including reperfusion injury, disruption to the blood-brain barrier, excitotoxicity, and metabolic dysregulation. There are currently no effective pharmacological treatments in the wide-spread use for TBI, in large part due to challenges associated with the development of clinically representative in vitro and in vivo models. Poloxamer 188 (P188), a Food and Drug Administration-approved amphiphilic triblock copolymer embeds itself into the plasma membrane of damaged cells. P188 has been shown to have neuroprotective properties on various cell types. The objective of this review is to provide a summary of the current literature on in vitro models of TBI treated with P188. [ABSTRACT FROM AUTHOR]

This study focuses on the development of high temperature polymer electrolyte membranes (HT-PEMs), which are essential components for HT-PEM fuel cells (HT-PEMFCs). While phosphoric acid (PA) doped polybenzimidazole (PBI) has been recognized as a successful HT-PEM, it faces several challenges, including the use of carcinogenic monomer, complex synthesis processes, and poor solubility in organic solvents. To produce more cost-effective, easily synthesized, and high-performance alternatives, this study utilizes a straightforward superacid-catalyzed Friedel-Crafts reaction to synthesize a series of poly(terphenyl- co -dibenzo-18-crown-6 methylimidazole) copolymers, referred to as Co- x %TP- y %CE-Im, using p -terphenyl, dibenzo-18-crown-6 and 1-methyl-1H-imidazole-2-formaldehyde as monomers. The copolymerized hydrophilic and bulky crown ether units introduce substantial free volume and multiple interaction sites with PA molecules, as indicated by theoretical calculations. Additionally, the formation of microphase separation structures, confirmed by atomic force microscope (AFM) and transmission electron microscope (TEM), contributes to the enhanced performance of these membranes. For instance, after immersion in 85 wt% and 75 wt% PA solutions, the Co-90%TP-10%CE membrane achieves PA doping contents of 200 % and 169 %, achieving high conductivities of 0.092 S cm−1 and 0.054 S cm−1 at 180 °C, while maintaining tensile strengths of 6.5 MPa and 7.5 MPa at room temperature. Without the need for humidification or backpressure, the peak power density of an H 2 -O 2 cell equipped with Co-90%TP-10%CE/169%PA membrane with a thickness of 79 μm reaches an impressive 1018 mW cm−2 at 210 °C. These results demonstrate new materials and insights for the development of high-performance HT-PEMs. [Display omitted] • Poly(triphenyl-co-dibenzo-18-crown-6 methylimidazole) copolymers are synthesized through a facile procedure. • Crown ether units endow membranes with multiple hydrogen bonding sites and microphase separation structures. • H 2 –O 2 fuel cell with Co-90%TP-10%CE-Im/169%PA achieves a high peak power density of 1072 mW cm−2 at 210 °C. [ABSTRACT FROM AUTHOR]

Gas transport properties of thermally rearranged polybenzoxazoles without fluorene rings (TR-coPBOs) were studied. Specific volumes (V sp s) of the TR-coPBOs were larger than the values predicted by the theoretical additive rule, stating that copolymerizing heterogeneous structures into a part of the rigid main chains caused inhibition of molecular chain packing. Gas permeability coefficients of the TR-coPBOs exceeded those predicted by the theoretical semi-logarithmic additivity and came to be maximized at the copolymerization of 10 mol% of heterogeneous units. The increasing gas permeability could be attributed to the increasing free volumes due to the copolymerization of heterogeneous units. Despite the specific increase in CO2 permeability by the copolymerization, the TR-coPBOs possessed high CO2/CH4 selectivity. This fact demonstrated the TR-coPBOs could achieve simultaneously high CO2 permeability and CO2/CH4 selectivity, maintaining inherent high CO2/CH4 permselectivity. [ABSTRACT FROM AUTHOR]

The influence of the nature of modified fillers (Ni- and Cu-containing polymer-silicate materials) on the kinetics of emulsion polymerization of methylmethacrylate in the presence of polyvinylpyrrolidone graft copolymers was investigated. The features of polymer formation of polymethylmethacrylate materials depending on the nature of the filler and process conditions are considered. The polymerization process occurs through several stages and is characterized by an induction period. High surface hardness and Vicat softening point characterize the developed materials obtained based on filled compositions. [ABSTRACT FROM AUTHOR]

• Synthesis of novel composite is based on HAP@PANI@PoPD in situ co-polymerization. • The composite attained 99% dye removal at an initial concentration of 50 mg/L. • Optimum condition: 0.5 and 1 g/L for OG and TB dye; pH 2, 800 rpm of agitation speed. • The Temkin model was appropriate for describing the adsorption of OG dye. • The Redlich-Peterson and Toth models provided a good fit for the TB adsorption. • The composite could be regenerated five consecutive times with 80% efficiency. Acid dyes in any water source strongly impact its color, blocking sunlight and harming aquatic life. Herein, the technical applicability of a novel composite based on hydroxyapatite and poly(aniline- o -phenylenediamine) for removing dyes from synthetic wastewater was investigated using a batch method. In this work, camel bones were used as a source of hydroxyapatite. Camel bones were pretreated in an alkali environment before extracting hydroxyapatite biocrystal (HAP). Subsequently, the extracted HAP was mixed with the poly(aniline- o -phenylenediamine) (PANI@PoPD) co-polymer. Different formulation methods were designed to optimize the tested composite samples' shape, size, structure and composition. Then, the optimized composite was further used as an adsorbent to remove orange G (OG) and thymol blue (TB) dyes from synthetic wastewater. The effects of the composite's dose, pH, dyes' initial concentration and temperature on the overall performance of the composite were assessed. Statistical tests were then used to test the best experimental conditions to remove target dyes from wastewater. By keeping the dye concentration constant at 50 mg/L for both OG and TB in wastewater at 25 °C, pH = 2 and 800 rpm of agitation speed in a batch reactor, it was found that the synthesized composite efficiently removes 99% of each dye at optimum dose of 0.5 or 1 g/L with a reaction time close to 30 or to 80 min for OG or TB, respectively. The predictive capacity of two-parameter models, including the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models, and three-parameter models such as the Redlich-Peterson, Sips and Toth models, was assessed to estimate the collected adsorption data. It was found that the statistical analysis was slightly better when the Temkin model was applied. This indicates that this equation was better suited to represent the experimental data of the adsorption of the OG dye. In contrast, the Redlich-Peterson and Toth models were in better agreement with the experimental results of the TB dye adsorption. Furthermore, thermodynamic parameters associated with each dye adsorption demonstrated its feasibility, while the adsorption kinetic data were found to be better described with the pseudo-second-order kinetics. In addition, the regenerability performances of the tested composite were successfully assessed by reusing the spent composite five consecutive times. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Magnetorheological fluids (MRFs) have been successfully used in a variety of smart control systems, but are still limited due to their relatively poor settling stability. Herein, a core/shell‐structured Fe3O4/copolymer composite nanoparticle is synthesized as a new candidate material for stimulus‐responsive MRFs to tackle the limitation of the long‐term dispersion stability. Aniline‐co‐diphenylamine copolymers (PANI‐co‐PDPA) are loaded onto the surface of Fe3O4 nanoparticles, providing a lighter density and sufficient active interface for the dispersion of magnetic particles in the carrier medium. The features of the Fe3O4/copolymer composite nanoparticles, including morphology, compositional, and crystalline properties, are characterized. An MRF is prepared by suspending Fe3O4/copolymer composite nanoparticles in a nonmagnetic medium oil, and its rheological properties are assessed using a controlled shear rate test and dynamic oscillation tests using a rotational rheometer. Rheological models including the Bingham model and the Herschel–Bulkley model are fitted to the flow curves of the MRF. The obtained Fe3O4/copolymer composite shows soft‐magnetic properties, as well as greater density adaptability and higher stability, compared to Fe3O4. Moreover, the sedimentation testing provides information about the dispersion stability characteristics of MRF and shows a good correlation with high‐stability magnetorheological (MR) response. The Fe3O4/copolymer‐based MRF with a tunable and instantaneous MR response is considered a promising material for smart control applications.

Micelles were prepared by the crosslinking copolymerization of casein and dextran in the Maillard reaction. Glycated proteins were identified using ft-IR spectrometry. Solutions of micelles are characterized by changing of optical properties. Micellization is reversible depending on pH. Micelles size ranges from 400 to 2000 nm when pH 4.6 and micelles dissociate at pH 7.0. Micelles can be used to encapsulate hydrophobic substances in the food industry.

Traditional electrochemical biosensors often rely on expensive materials like gold nanoparticles within their electrode structures. In contrast to existing methods, this research introduces a novel, groundbreaking, label-free aptasensor. This sensor comprises simple and inexpensive materials, making it accessible and budget-conscious. It boasts exceptional sensitivity, allowing for the identification of leukemia cancer biomarker (miRNA-155) in its early stages. The proposed aptasensor consisted of a copolymer of poly anthranilic acid and polyaniline on the graphite sheet, in which the receptor of miRNA-155 was self-assembled on the copolymer. The substrate of receptors has benefits, including high electrical conductivity, excellent stability, good biocompatibility, and simple synthesis. The important variables affecting the adequacy of the designed aptasensor were examined in the presence of [Fe(CN) 6 ]3-/4- as a redox probe. The proposed aptasensor was successfully used in human blood plasma. Due to the ease of preparation, cost, and time effectiveness, the proposed aptasensor is promising for mass production. Finally, at optimum conditions, the sensor exhibited a linear response within a concentration range of 0.1 nM to 1 aM with a detection limit of 1 aM. [Display omitted] • A label-free electrochemical aptasensor for early diagnosis of miR-155 biomarker. • PAA-PANI copolymer was electrosynthesized in a short time on GS as a very cheap substrate. • At the optimum conditions, the linear range of response was 0.1 nM to 1 aM. • Selectivity was good; mismatches' response is about 10 % of the target response. • The aptasensor was applied successfully in the human blood serum. [ABSTRACT FROM AUTHOR]

[Display omitted] • High stretchability and interfacial robustness of the copolymer-based substrate. • Exceptional strain-shielding property of strain-engineered substrate. • High electrical stability under external strain of substrate. • This substrate enables the fabrication of stretchable and conformable electronics. • Demonstrates great potential as an engineered substrate for array device fabrication. The challenge of integrating electronic components into soft substrates to consolidate diverse device functionalities into a single wearable unit impedes the advancement and application of emerging soft and stretchable electronics. This is primarily due to the tendency of rigid components to be detached from deformable substrates under mechanical stress such as repetitive stretching, due to significant differences in the elastic modulus of dissimilar materials. Therefore, it is essential to employ strategies that prevent electrical and mechanical failures when incorporating rigid components into stretchable systems. To address this issue, stiff islands of a copolymer were incorporated into a soft copolymer substrate, ensuring stable interfaces between rigid and stretchable regions. In this work, polyimide-siloxane copolymers with adjustable compositions of hard and soft blocks with mechanical modulus tuneability were employed to fabricate a strain-engineered substrate (SES). The resulting SES demonstrated exceptional strain shielding properties, preventing electronic components from being detached under strain levels of up to 266%. This substrate, engineered to endure strain, exhibited a resistance variation of less than 4% for the gold electrode on it when stretched cyclically up to 5000 cycles at 15% strain. A stretchable supercapacitor and triboelectric sensor with high stability could be fabricated on the SES. The SES enabled a robust interface capable of mitigating local strain on rigid components while preserving the stretchability of the soft substrates, which helps prevent potential damage to the rigid components. By alleviating the issues of unstable interfaces and mechanical and electrical failure, our approach of the SES has great potential in wearable electronics. [ABSTRACT FROM AUTHOR]

Poly (β-amino ester) (PBAE) is an exceptional non-viral vector that is widely used in gene delivery, owing to its exceptional biocompatibility, easy synthesis, and cost-effectiveness. However, it carries a high surface positive charge that may cause cytotoxicity. Therefore, hydrophilic d-α-tocopherol polyethylene glycol succinate (TPGS) was copolymerised with PBAE to increase the biocompatibility and to decrease the potential cytotoxicity of the cationic polymer-DNA plasmid polyplex nanoparticles (NPs) formed through electrostatic forces between the polymer and DNA. TPGS-b-PBAE (TBP) copolymers with varying feeding molar ratios were synthesised to obtain products of different molecular weights. Their gene transfection efficiency was subsequently evaluated in HEK 293T cells using green fluorescent protein plasmid (GFP) as the model because free GFP is unable to easily pass through the cell membrane and then express as a protein. The particle size, ζ-potential, and morphology of the TBP2-GFP polyplex NPs were characterised, and plasmid incorporation was confirmed through gel retardation assays. The TBP2-GFP polyplex NPs effectively transfected multiple cells with low cytotoxicity, including HEK 293T, HeLa, Me180, SiHa, SCC-7 and C666-1 cells. We constructed a MUC2 (Mucin2)-targeting CRISPR/cas9 gene editing system in HEK 293T cells, with gene disruption supported by oligodeoxynucleotide (ODN) insertion in vitro. Additionally, we developed an LMP1 (latent membrane protein 1)-targeting CRISPR/cas9 gene editing system in LMP1-overexpressing SCC7 cells, which was designed to cleave fragments expressing the LMP1 protein (related to Epstein–Barr virus infection) and thus to inhibit the growth of the cells in vivo. As evidenced by in vitro and in vivo experiments, this system has great potential for gene therapy applications.

Novel composite membranes employing a poly(ether-block-amide) (PEBAX) copolymer and sulfonated montmorillonite (S-MMT) as a filler were developed. The ratio of polyether to polyamide blocks was investigated using PEBAX 2533 and PEBAX 4533 based on the membrane properties and performance. Additionally, the effect of the changing filler ratio was monitored. The interaction between the S-MMT as nanofiller and the polymer matrix of PEBAX2533 and PEBAX4533 as well as the crystalline nature and thermal and mechanical stability of the composite membranes were evaluated using Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and tensile test. The composite membrane with 7 wt.% S-MMT showed the highest water uptake of 21% and 16% and an acceptable swelling degree of 16% and 9% for PEBAX 2533 and PEBAX 4533 composite membranes, respectively. In terms of water uptake and ion exchange capacity at room temperature, the new un-protonated membranes are superior to un-protonated Nafion. Meanwhile, with the same S-MMT content, the ion conductivity of PEBAX 2533 and PEBAX 4533 composite membranes is 2 and 1.6 mS/cm, and their ion exchange capacity is 0.9 and 1.10 meq/g.

The release of drugs from core/shell nanoparticles (NPs) is a crucial factor in ensuring high reproducibility, stability, and quality control. It serves as the scientific basis for the development of nanocarriers. Several factors, such as composition, composition ratio, ingredient interactions, and preparation methods, influence the drug release from these carrier systems. The objective of our study was to investigate and discuss the relationship between modifications of core/shell NPs as multifunctional drug delivery systems and the properties and kinetics of drug release using an in vitro drug release model. In this paper, we prepared four core/shell NPs consisting of a superparamagnetic iron oxide NPs (Fe3−δO4) core encapsulated by a biocompatible thermo-responsive copolymer, poly(2-(2-methoxy) ethyl methacrylate-oligo (ethylene glycol) methacrylate) or P(MEO2MAx-OEGMA100−x) (where x and 100 − x represented the molar fractions of MEO2MA and OEGMA, respectively), and loaded with doxorubicin (DOX). Colloidal behavior measurements in water and PBS as a function of temperature showed an optimization of the lower critical solution temperature (LCST) depending on the molar fractions of MEO2MA and OEGMA used to form each NPs. In vitro studies of doxorubicin release as a function of temperature demonstrated a high control of release based on the LCST. A temperature of approximately 45 °C for 60 h was sufficient to release 100% of the DOX loaded in the NPs for each sample. In conclusion, external stimuli can be used to modulate the drug release behavior. Core/shell NPs hold great promise as a technique for multifunctional drug delivery systems.

Xanthan gum modification is considered a significant step in improving shearing, thermal degradation performance, and rheological properties. This paper investigates the rheology properties of the grafted copolymer based on xanthan gum and methyl methacrylate (XG-g-MMA), including shear stress and viscosity versus shear rate. The grafted copolymer XG-g-MMA was synthesized with different composition ratios of methyl methacrylate (MMA) (1:1.6, 1:5, and 1:8 wt.%) in the presence of a potassium persulphate initiator. Fourier transform infrared spectroscopy (FTIR) characterized the obtained grafted xanthan gum (XG) to confirm the grafting process. The results of the rheology analysis show that grafted XG exhibited higher shear stress and viscosity than pure XG. However, increasing the MMA ratio increases shear stress and viscosity with increasing shear rate. In addition, the rheology measurement of the grafted copolymer showed non-Newtonian shear thinning behavior for XG and XG-g-MMA. These results can further its application in different fields, such as oil recovery and pharmaceuticals.

Abstract Background Age-driven immune signals cause a state of chronic low-grade inflammation and in consequence affect bone healing and cause challenges for clinicians when repairing critical-sized bone defects in elderly patients. Methods Poly(l-lactide-co-ɛ-caprolactone) (PLCA) scaffolds are functionalized with plant-derived nanoparticles from potato, rhamnogalacturonan-I (RG-I), to investigate their ability to modulate inflammation in vitro in neutrophils and macrophages at gene and protein levels. The scaffolds’ early and late host response at gene, protein and histological levels is tested in vivo in a subcutaneous rat model and their potential to promote bone regeneration in an aged rodent was tested in a critical-sized calvaria bone defect. Significant differences were tested using one-way ANOVA, followed by a multiple-comparison Tukey’s test with a p value ≤ 0.05 considered significant. Results Gene expressions revealed PLCA scaffold functionalized with plant-derived RG-I with a relatively higher amount of galactose than arabinose (potato dearabinated (PA)) to reduce the inflammatory state stimulated by bacterial LPS in neutrophils and macrophages in vitro. LPS-stimulated neutrophils show a significantly decreased intracellular accumulation of galectin-3 in the presence of PA functionalization compared to Control (unmodified PLCA scaffolds). The in vivo gene and protein expressions revealed comparable results to in vitro. The host response is modulated towards anti-inflammatory/ healing at early and late time points at gene and protein levels. A reduced foreign body reaction and fibrous capsule formation is observed when PLCA scaffolds functionalized with PA were implanted in vivo subcutaneously. PLCA scaffolds functionalized with PA modulated the cytokine and chemokine expressions in vivo during early and late inflammatory phases. PLCA scaffolds functionalized with PA implanted in calvaria defects of aged rats downregulating pro-inflammatory gene markers while promoting osteogenic markers after 2 weeks in vivo. Conclusion We have shown that PLCA scaffolds functionalized with plant-derived RG-I with a relatively higher amount of galactose play a role in the modulation of inflammatory responses both in vitro and in vivo subcutaneously and promote the initiation of bone formation in a critical-sized bone defect of an aged rodent. Our study addresses the increasing demand in bone tissue engineering for immunomodulatory 3D scaffolds that promote osteogenesis and modulate immune responses.

A novel ammonium salt type polymeric antistatic agent (PDSH) was synthesized from methacrylatoethyl trimethyl ammonium chloride, styrene, and 2-hydroxyethyl methacrylate via radical polymerization. Antistatic poly(acrylonitrile-co-butadiene-co-styrene) (ABS)/PDSH composites were prepared by blending PDSH with ABS resin. The results showed that the surface resistivity of ABS/PDSH composites with PDSH addition decreased significantly. The surface resistivity of ABS/PDSH composites containing 20 wt% PDSH was around 109–1010 Ω, which was about 106 times lower than that of neat ABS. At the same time, ABS/PDSH composites had good thermal stability and hydrophilicity. The PDSH was more uniformly dispersed within the ABS resin and had less influence on the mechanical properties of the composites. With the demonstrated properties, the prepared copolymer PDSH can serve as a well-integrated antistatic agent and display potential for the antistatic treatment of ABS.

In order to investigate the effects of plasticizers on the binding energy, solubility parameter and mechanical properties of pBAMO-b-GAP copolymer (the copolymer of 3,3′-bis(azidomethy) oxetane and glycidyl azide polymer), the related copolymer/plasticizer mixed systems were established by molecular dynamics simulations. Besides, the mechanical properties of the formulas based on pBAMO-b-GAP containing the three energetic plasticizers were also studied experimentally. The results showed that all involved energetic plasticizers could be miscible with the pBAMO-b-GAP. The order of binding energy was theoretically found to be pBAMO-b-GAP / BuNENA > pBAMO-b-GAP/ TMETN > pBAMO-b-GAP/ DIANP which was consistent with the trends of the experimental tensile strength values of three mixed materials. Excitedly, the DIANP showed strongest effects among the three plasticizers on improving the toughness of the copolymer according to the calculation of Cauchy pressure and experimental value of elongation. For the pBAMO-b-GAP copolymer, the DIANP could be a promising plasticizer and compolymer/plasticizer mixed system was suitable used as binder in azido polyether-based propellants.

Polyhydroxyalkanoate (PHA) synthases (PhaCs) are key enzymes in PHA polymerization. PhaCs with broad substrate specificity are attractive for synthesizing structurally diverse PHAs. In the PHA family, 3-hydroxybutyrate (3HB)-based copolymers are industrially produced using Class I PhaCs and can be used as practical biodegradable thermoplastics. However, Class I PhaCs with broad substrate specificities are scarce, prompting our search for novel PhaCs. In this study, four new PhaCs from the bacteria Ferrimonas marina, Plesiomonas shigelloides, Shewanella pealeana, and Vibrio metschnikovii were selected via a homology search against the GenBank database, using the amino acid sequence of Aeromonas caviae PHA synthase (PhaCAc), a Class I enzyme with a wide range of substrate specificities, as a template. The four PhaCs were characterized in terms of their polymerization ability and substrate specificity, using Escherichia coli as a host for PHA production. All the new PhaCs were able to synthesize P(3HB) in E. coli with a high molecular weight, surpassing PhaCAc. The substrate specificity of PhaCs was evaluated by synthesizing 3HB-based copolymers with 3-hydroxyhexanoate, 3-hydroxy-4-methylvalerate, 3-hydroxy-2-methylbutyrate, and 3-hydroxypivalate monomers. Interestingly, PhaC from P. shigelloides (PhaCPs) exhibited relatively broad substrate specificity. PhaCPs was further engineered through site-directed mutagenesis, and the variant resulted in an enzyme with improved polymerization ability and substrate specificity.

The copolymer of N,N-diallyl-N,N-dimethylammonium chloride and N-[3-(Dimethylamino)propyl]methacrylamide (DADMAC–DMAPMA) was synthesized by radical polymerization reaction in an aqueous solution in the presence of the initiator ammonium persulfate (NH4)2S2O8. The molar compositions of the synthesized copolymers were determined using FTIR and 1H NMR-spectroscopy, elemental analysis, and conductometric titration. It was found that in the radical copolymerization reaction, the DMAPMA monomer was more active than the DADMAC monomer; for this reason, the resulting copolymers were always enriched in the DMAPMA monomers. The study of the influence of the DADMAC–DMAPMA copolymer on structure-formation in the bentonite suspension showed that this copolymer significantly increased the static shear stress (SSS) of the system. In this case, the structure-forming properties of the copolymer depended on the pH of the medium. The lower the pH level, the better the structure-formation was in the suspension in the presence of the copolymer. The study of antibacterial activity showed that the DADMAC–DMAPMA copolymer had a biocidal effect against sulfate-reducing bacteria (CRB) at a concentration of not less than 0.05 wt.% and can be used to inhibit the growth of this bacteria. [ABSTRACT FROM AUTHOR]

One of the most widely used conductive polymers in the growing conductive polymer industry is poly(3,4-ethylenedioxythiophene) (PEDOT), whose main advantages are good thermal and chemical stability, a conjugated backbone, and ease of functionalization. The main drawback of PEDOT for use as wearable electronics is the lack of stretchable and self-healing properties. This can be overcome by grafting PEDOT with flexible side branches. As pure PEDOT is highly stable and grafting would not be possible, a new bromine-functionalized thiophene derivative, 2-(tiophen-3-yl) ethyl 2-bromo-2-methylpropanoate (ThBr), was synthesized and copolymerized with EDOT for the synthesis of a poly(EDOT-co-ThBr) ATRP macroinitiator. After the synthesis of the macroinitiator, flexible polymers could be introduced as side branches by atom-transfer radical polymerization (ATRP) to modify mechanical properties. Before this last synthesis step, the conditions for the synthesis of the ATRP macroinitiator should be investigated, as only functionalized units can function as grafting sites. In this study, nine new copolymers with different monomer ratios were synthesized to investigate the reactivity of each monomer. The ratios used in the different syntheses were ThBr:EDOT = 1:0.2, 1:0.4, 1:0.6, 1:0.8, 1:1, 0.8:1, 0.6:1, 0.4:1, and 0.2:1. In order to determine the effect of reaction time on the final properties of the polymer, macroinitiator synthesis at a 1:1 ratio was carried out at different time periods: 8 h, 16 h, 24 h, and 48 h. The obtained products were characterized by different techniques, and it was found that polymerizations longer than 24 h yielded practically insoluble macroinitiators, thus limiting its further application. Reactivity ratios of both monomers were found to be similar and close to 1, making the copolymerization reaction symmetrical and the obtained macroinitiators almost random copolymers. [ABSTRACT FROM AUTHOR]

The inflammability of polystyrene (PS) limited its application. In order to improve the flame retardancy of PS, developing reactive-type flame retardants is a promising approach. In this work, a novel N-arylpiperazine phosphoramidate monomer, 2-((phenoxy(4-phenylpiperazin-1-yl)phosphoryl)oxy)ethyl methacrylate (PPPEM), was facilely synthesized and used as a reactive-type flame retardant. The obtained monomer was then copolymerized with styrene through the free radical bulk polymerization. The thermal stability of copolymers was measured by the thermogravimetric analysis. The addition of the PPPEM units increased decomposition temperature of the copolymers, indicating the improvement of the thermal stability. The glass transition temperature of the copolymers remained little changed with varied amount of the PPPEM, implying that the introduction of PPPEM units did not evidently affect the mobility of the PS main chain. The flammability of the copolymers was evaluated by microscale combustion calorimeter (MCC) and limiting oxygen index (LOI). According to the MCC and LOI results, PPPEM unites can contribute to the decrease of the peak heat release rate, the increase of LOI and improvement of the flame retardancy. The novel N-arylpiperazine phosphoramidate monomer show a great potential for application in reactive-type flame retardants. [ABSTRACT FROM AUTHOR]

Sulfonated polysulfone membranes are among the best candidate for fuel cells. The main challenges are obtaining high conductivity and mechanical properties. Accordingly, disulfonated poly(ether sulfide sulfone) copolymer flexible films were prepared via reaction of bis(4-hydroxyphenyl) sulfide with sulfonated and non-sulfonated bis(4-fluorophenyl) sulfone, and subsequent solution casting. Thermal and mechanical properties, water uptake, oxidative stability, and ion exchange capacity were investigated. Proton conductivity of copolymers at 80°C was 0.131–0.198 S cm−1. Polymer with 45% degree of sulfonation showed optimized favorable properties. Copolymers indicated acceptable properties compared with Nafion that was partially related to the presence of flexible hydroxyphenyl sulfide moiety. [ABSTRACT FROM AUTHOR]

A new adsorbent of CMC-g-Poly(MAA-co-AAm)/Cloisite 30B (Hyd/C30B) nanocomposite hydrogel was synthesized by the free radical polymerization approach to eliminate methylene blue (MB) dye from wastewater samples. The BET value for C30B, Hyd, and Hyd/C30B was determined 5.00, 0.83, and 2.42 m2/g, respectively, while, based on the MB removal method, the surface area for the mentioned adsorbents was calculated 133.12, 129.53, and 149.61 m2/g, respectively. The generated nano-hydrogel belonged to a type IV isotherm and had a pore size of 2–50 nm. In the MB adsorption process using the desired adsorbents, the maximum adsorption was attained at pH 8, temperature of 45 °C, time of 30 min, adsorbent dose of 0.8 g/L, and dye concentration of 10 mg/L. The swelling rate of the studied hydrogel depended on pH and temperature. The adsorption process increased with increasing temperature. The Gibbs free energy parameter and enthalpy had negative values, indicating that the degree of the spontaneity of the adsorption process increased at high temperatures. The data followed pseudo-second-order kinetic and Langmuir isotherm. The maximum MB adsorption using Hyd, Hyd/C30B, and C30B was computed to be 67.11 mg/g, 77.51 mg/g, and 70.42 mg/g, respectively. The adsorbents had a good ability to reduce industrial wastewater pollutants. [ABSTRACT FROM AUTHOR]

Photo‐controlled polymerizations are attractive to tailor macromolecules of complex compositions with spatiotemporal regulation. In this work, with a convenient synthesis for trifluorovinyl boronic ester (TFVB), we report a light‐driven organocatalyzed copolymerization of vinyl monomers and TFVB for the first time, which enabled the controlled synthesis of a variety of hybrid fluorine/boron polymers with low dispersities and good chain‐end fidelity. The good behaviors of "ON/OFF" switch, chain‐extension polymerizations and post‐modifications further highlight the versatility and reliability of this copolymerization. Furthermore, we demonstrate that the combination of fluorine and boron could furnish copolymer electrolytes of high lithium‐ion transference number (up to 0.83), bringing new opportunities of engineering high‐performance materials for energy storage purposes. [ABSTRACT FROM AUTHOR]

Nitrogen dioxide (NO2) sensors utilising graft copolymers bearing poly(3-hexylthiophene) chains have been developed and investigated in terms of their operation parameters using different carrier gases (N2 or air) and in either dark conditions or with ultraviolet (UV) irradiation. Interestingly, sensor performance improved upon transition from N2 to air, with the inverse being true for most NO2 sensors. UV irradiation both improved sensor dynamics and stabilised the sensor electrical baseline, allowing sensors based on SilPEG to fulfil the requirements of sensing solutions used in industry (below 10% baseline drift after sensors reach saturation) and making them promising candidates for further development and applications. Based on conducted multi-variate experiments, an initial mechanism underlying the interplay of exposure to oxygen (present in air) and UV irradiation was postulated. [ABSTRACT FROM AUTHOR]

In this research the effect of physical recycling on the mechanical, thermal, and rheological properties of polypropylene (PP)/multiwalled carbon nanotube (MWCNT) was investigated. After melt homogenization by extrusion, specimens were injection moulded with 0.1 and 0.5 wt% MWCNT content. The recycling process was simulated by multiple grinding and re-moulding, then we compared the behavior of original and recycled PP/MWCNT composites. Differential scanning calorimetry (DSC) measurements proved that MWCNT had double the effect on the morphology of the PP matrix: on the one hand nucleating effect can be detected because 0.5 wt% MWCNT increased the onset temperature of crystallization by 10 °C, compared to the basic PP material; on the other hand, the crystalline fraction of the recycled composite materials decreased compared to the original PP material with the same MWCNT content. This resulted in a slight decrease in strength and stiffness but an increase in elongation at break. However, compared to the original unreinforced PP reference, even the recycled materials have better properties. The mechanical test results showed that recycled PP/MWCNT 0.5 wt% increased the elastic modulus (~15%) and decreased the tensile strain at yield (~10%). However, in the values of tensile stress at yield, relevant difference was not found. It was also shown by oscillatory rheometry that MWCNT had a significant effect on the rheological properties (storage and loss modulus, complex viscosity) of PP compounds in a wide temperature range (190–230 °C). [ABSTRACT FROM AUTHOR]

Polypropylene (PP) is one of the most widely used commodity plastic materials worldwide in terms of the production and its consumption. At commercial scale, PP is produced in various grades like homopolymer and copolymer (random and impact) by the polymerization of propylene and mixture of propylene-ethylene monomers using Ziegler–Natta catalysts and alkyl aluminum as co-catalysts. The present study deals with the colored lump formation of polypropylene random copolymer (PPCP) during storage at large scale and its probable route cause analysis for the lump formation. The lump samples were collected and characterized using FTIR, TGA, DSC and molecular weight determination and compared with pure PPCP. FTIR data show all the signature peaks of PPCP with additional > C=O stretching near 1720 cm−1 in colored lump sample, TG analysis revealed degradation of PPCP polymer and formation of volatile organic compounds in the temperature range 200–250 °C, the DSC analysis of the colored lump and pure PPCP showed that the melting peak was broader for colored lump of PPCP (i.e., PPCP_Y) which is an indicative that polymer molecules were having different chain length and the molecular weight analysis showed that the colored sample was having very low molecular weight with some bimodal character as compared to pure polymer. Based on these data and observations, the possible reason for the colored lump formation was also discussed. [ABSTRACT FROM AUTHOR]

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Self-compacting concrete (SCC) is an extremely flowable concrete, which increases the probability of segregation and bleeding. Viscosity-modifying admixtures (VMAs) have been developed to improve the stability of SCC. Synthetic polymer VMAs have excellent water solubility and stability, and can be easily chemically prepared and modified. In this work, a series of copolymers based on anionic 2-acrylamido-2-methyl-propanesulfonic acid (AMPS) and nonionic N, N-dimethyl acrylamide (DMAA), with similar molecular weights but different charge densities, were prepared. The effect of the charge density of the anionic polymers on the fluidity, rheological property, and adsorption behavior of the cement pastes was investigated. The action mechanism of the polymers was discussed. The results indicate that the charge density of anionic polymer VMAs is of great significance for the development of cost-effective SCCs with good rheological properties. [ABSTRACT FROM AUTHOR]

Glycidyl azide polymer (GAP) is a known prepolymer for energetic binder applications. However, its application has been limited due to its relatively poor mechanical and low-temperature properties. For instance, the glass transition temperature (Tg) of GAP (–45 °C) restricts its mobility and flexibility. The flexibility will affect the mechanical properties such as modulus, strength, and elongation of this energetic binder in the propellant. Due to the good thermal and mechanical properties of polypropylene glycol (PPG), the copolymerization of GAP with this binder is a useful strategy for the improvement of its mechanical properties. In the present work, the polyurethane elastomers (PUEs) of polypropylene glycol- glycidyl azide polymer- polypropylene glycol (PPG-GAP-PPG) triblock were copolymer prepared for the first time. For this purpose, the synthesized PPG-GAP-PPG binder was cured using different isocyanates such as isophorone diisocyanate (IPDI), toluene diisocyanate (TDI), and desmodour N-100, as well as their mixtures. The 5% BuNENA as a more compatible plasticizer, shows the best result in mechanical properties compared to another one. Also, the optimized [NCO]/[OH] ratio was determined to be 1.20, and the best curing results were obtained using the equal weights of IPDI/N100 curing agents and DBTDL as a catalyst. The mechanical properties of synthesized polyurethane elastomers were studied using the elongation test. The prepared polyurethane elastomer using the combination of 50/50 IPDI/N100 incorporated BuNENA as a plasticizer showed 96% elongation at the break and 0.16 MPa tensile strength. The dynamical mechanical thermal analysis (DMTA) and differential scanning calorimetry (DSC) was also used to investigate the thermal properties. [ABSTRACT FROM AUTHOR]

Aniline (Ani) and pyrrole (Py) based copolymers (poly(Ani-co-Py)) were fabricated by varying the reaction time ranging from 4 to 8 h through chemical oxidative polymerization technique. The photocatalytic performance and the application as supercapacitors of prepared copolymers were assessed together with the studies of their morphological features. The formation of poly(Ani-co-Py) copolymers was confirmed by FTIR, UV–Vis, and photo-luminescence (PL) spectroscopy. All the copolymers demonstrated almost similar morphology, like irregular, aggregated, and spherical-shaped structures, investigated by field-emission scanning electron microscopy (FESEM). Such morphology was different from the individual polymer of PANI (rod-like) and PPy (spherical) although diameters remained similar in the range of 50–200 nm for the homo and copolymers. The prepared copolymers showed excellent photocatalytic representation towards methylene blue (MB) degradation in comparison to the PANI and PPy. The supercapacitors fabricated using poly(Ani-co-Py) copolymers also showed promising prospects for the hybrid supercapacitor. These findings may provide a new insight to fabricate poly(Ani-co-Py) photocatalysts for organic pollutants treatment as well as may have potential prospects for supercapacitor. [Display omitted] • Simple fabrication of poly(Ani-co-Py) copolymer is reported. • The morphological distinctions of the poly(Ani-co-Py) was identified in comparison to PANI and PPy. • Copolymers showed excellent photocatalytic representation towards methylene blue removal than polymer. • Supercapacitor fabricated using poly(Ani-co-Py) showed superb performance. [ABSTRACT FROM AUTHOR]