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Methyl acrylate has a wide range of uses, but the production process usually produces aqueous by-products. In this study, four commonly used alcohols (1-pentanol, 1-hexanol, 1-heptanol, and 1-octanol) were selected as extractants to explore the liquid–liquid extraction behavior of water + methyl acrylate + extractants. Through the analysis of partition coefficient (D) and separation coefficient (S), it is found that the data of all systems are greater than 1, indicating that all four alkyl alcohols can well separate methyl acrylate from aqueous solution, and 1-octanol is the best. In addition, the consistency between the binary interaction parameters of regression and tie-line data was tested using Matlab tools, proving that the obtained parameters have good consistency. [ABSTRACT FROM AUTHOR]

An efficient method is developed to prepare copolymer of Poly(styrene-co-methylacrylate) using silver nanoparticle decorated reduced graphene oxide (Ag-rGO) under photocatalytic conditions using blue LED as light source. We have successfully utilised the prepared poly(styrene-co-methylacrylate) copolymer-based Ag-rGO nanocomposite (Ag-rGO/(P(S-co-MA) as a filler for reinforcing epoxy composite. Better dispersibility of the hybrid nanocomposite in diglycidyl ether of bisphenol A (DGEBA) over Ag-rGO helped in enhancing the mechanical properties of epoxy. The synthesis of P(S-co-MA)-Ag-rGO was confirmed using various characterization techniques like 1H NMR, 13C-NMR, FTIR etc. The particle size distribution and surface morphology were investigated using Field emission scanning electron microscopy (FE-SEM). The mechanical properties of P(S-co-MA)-Ag-rGO based epoxy composites showed a significant 104% of improvement in fracture toughness when compared to neat epoxy. Antibacterial performance and thermal characteristic of the fabricated epoxy composites also were investigated. [ABSTRACT FROM AUTHOR]

Despite their industrial ubiquity, polyolefin‐polyacrylate block copolymers are challenging to synthesize due to the distinct polymerization pathways necessary for respective blocks. This study utilizes MILRad, metal–organic insertion light‐initiated radical polymerization, to synthesize polyolefin‐b‐poly(methyl acrylate) copolymer by combining palladium‐catalyzed insertion–coordination polymerization and atom transfer radical polymerization (ATRP). Brookhart‐type Pd complexes used for the living polymerization of olefins are homolytically cleaved by blue‐light irradiation, generating polyolefin‐based macroradicals, which are trapped with functional nitroxide derivatives forming ATRP macroinitiators. ATRP in the presence of Cu(0), that is, supplemental activators and reducing agents , is used to polymerize methyl acrylate. An increase in the functionalization efficiency of up to 71% is demonstrated in this study by modifying the light source and optimizing the radical trapping condition. Regardless of the radical trapping efficiency, essentially quantitative chain extension of polyolefin‐Br macroinitiator with acrylates is consistently demonstrated, indicating successful second block formation. [ABSTRACT FROM AUTHOR]

The present work proposes to investigate the effect of an ultrahigh molecular weight silicone rubber (UHMW-SR) and two ethylene methyl acrylate copolymers (EMA) with different methyl acrylate (MA) content on the mechanical and fire performance of a fireproof acrylonitrile butadiene styrene copolymer (ABS) composite, with an optimum amount of ammonium polyphosphate (APP) and aluminum diethyl phosphinate (AlPi). ABS formulations with a global flame retardant weight content of 20 wt.% (ABS P) were melt-compounded, with and without EMA and UHMW-SR, in a Brabender mixer. During this batch process, ABS P formulations with UHMW-SR and/or EMA registered lower torque values than those of ABS P. By means of scanning electron microscopy (SEM), it was possible to observe that all ABS composites exhibited a homogenous structure without phase separation or particle agglomeration. Slightly improved interfacial interaction between the well-dispersed flame-retardant particles in the presence of EMA and/or UHMW-SR was also noticed. Furthermore, synergies in mechanical properties by adding both EMA and UHMW-SR into ABS P were ascertained. An enhancement of molecular mobility that contributed to the softening of ABS P was observed under dynamic mechanical thermal analysis (DMTA). An improvement of its flexibility, ductility and toughness were also registered under three-point-bending trials, and even more remarkable synergies were noticed in Charpy notched impact strength. Particularly, a 212% increase was achieved when 5 wt.% of EMA with 29 wt.% of MA and 2 wt.% of UHMW-SR in ABS P (ABS E29 S P) were added. Thermogravimetric analysis (TGA) showed that the presence of EMA copolymers in ABS P formulations did not interfere with its thermal decomposition, whereas UHMW-SR presence decreased its thermal stability at the beginning of the decomposition. Although the addition of EMA or UHMW-SR, as well as the combination of both in ABS P increased the pHRR in cone calorimetry, UL 94 V-0 classification was maintained for all flame-retarded ABS composites. In addition, through SEM analysis of cone calorimetry sample residue, a more cohesive surface char layer, with Si-O-C network formation confirmed by Fourier transform infrared (FTIR), was shown in ABS P formulations with UHMW-SR. [ABSTRACT FROM AUTHOR]

It has been shown that there exist conditions under which thermosensitive copolymers of N-vinylpyrrolidone with methyl acrylate form hydrophobic–hydrophilic associations, which are unstable dynamic meshes, the bonds in which are continuously broken and created again, and the nature of the formation of such meshes depends significantly on the proportion of the hydrophobic component in the copolymer. It is shown that the interaction of the above copolymers with polyacrylic acid results in the formation of not only classical interpolymer complexes, but also hydrophilic interpolymer associates, which also represent unstable networks existing in a dynamic mode. In such meshes, the molecules of the above copolymers serve as a kind of cross-agent connecting the polyacid molecules. There are also conditions under which such meshes acquire a complex structure, since unstable bonds between macromolecular tangles of both the same and different types take part in their formation. It is shown that the transition from the formation of interpolymer complexes to the formation of hydrophilic interpolymer associates can occur, among other things, due to changes in the acidity or concentration of low-molecular salt in solution. [ABSTRACT FROM AUTHOR]

Inspired by mussel chemistry, we presented a facile and eco‐friendly method to synthesize silver nanoparticles (AgNPs) using dopamine as a reductant and stabilizer. The synthesized AgNPs as an antibacterial agent and photothermal filler were further introduced to random copolymers of methyl methacrylate and butyl acrylate (MMA‐co‐BA) via latex mixing. The morphology and structure of the formed AgNPs were confirmed by transmission electron microscopy (TEM), UV–Vis spectrum, and x‐ray powder diffraction (XRD). The results showed that the synthesized AgNPs were spherical in the size of 5–30 nm with the characteristic crystalline structure of AgNPs. Mechanical properties of MMA‐co‐BA were significantly enhanced by the introduction of AgNPs. The MMA‐co‐BA/Ag nanocomposite films showed antibacterial activity against E. coli and S. aureus. Moreover, the scratches on the MMA‐co‐BA/Ag nanocomposite film can be healed under infrared light irradiation, which indicated that AgNPs enhanced the self‐healing ability of the MMA‐co‐BA. This work offers a viable avenue for developing antibacterial activity and self‐healing multifunctional coatings. Highlights: Silver nanoparticles modified by dopamine are introduced to acrylic copolymer.Acrylic copolymer/Ag nanocomposites exhibit antibacterial activity.Acrylic copolymer/Ag nanocomposites have photothermal performance.Acrylic copolymer/Ag nanocomposites have self‐healing ability. [ABSTRACT FROM AUTHOR]

Inspired by the drawstring structure in daily life, here we report the development of a drawstring‐mimetic supramolecular complex at the molecular scale. This complex consists of a rigid figure‐of‐eight macrocyclic host molecule and a flexible linear guest molecule which could interact through three‐point non‐covalent binding to form a highly selective and efficient host‐guest assembly. The complex not only resembles the drawstring structure, but also mimics the properties of a drawstring with regard to deformations under external forces. The supramolecular drawstring can be utilized as an interlocked crosslinker for poly(methyl acrylate), and the corresponding polymer samples exhibit comprehensive enhancement of macroscopic mechanical performance including stiffness, strength, and toughness. [ABSTRACT FROM AUTHOR]

Inspired by the drawstring structure in daily life, here we report the development of a drawstring‐mimetic supramolecular complex at the molecular scale. This complex consists of a rigid figure‐of‐eight macrocyclic host molecule and a flexible linear guest molecule which could interact through three‐point non‐covalent binding to form a highly selective and efficient host‐guest assembly. The complex not only resembles the drawstring structure, but also mimics the properties of a drawstring with regard to deformations under external forces. The supramolecular drawstring can be utilized as an interlocked crosslinker for poly(methyl acrylate), and the corresponding polymer samples exhibit comprehensive enhancement of macroscopic mechanical performance including stiffness, strength, and toughness. [ABSTRACT FROM AUTHOR]

Tailoring the hydrophobicity of supramolecular assembly building blocks enables the fabrication of well‐defined functional materials. However, the selection of building blocks used in the assembly of metal–phenolic networks (MPNs), an emerging supramolecular assembly platform for particle engineering, has been essentially limited to hydrophilic molecules. Herein, we synthesized and applied biscatechol‐functionalized hydrophobic polymers (poly(methyl acrylate) (PMA) and poly(butyl acrylate) (PBA)) as building blocks to engineer MPN particle systems (particles and capsules). Our method allowed control over the shell thickness (e.g. between 10 and 21 nm), stiffness (e.g. from 10 to 126 mN m−1), and permeability (e.g. 28–72 % capsules were permeable to 500 kDa fluorescein isothiocyanate‐dextran) of the MPN capsules by selection of the hydrophobic polymer building blocks (PMA or PBA) and by controlling the polymer concentration in the MPN assembly solution (0.25–2.0 mM) without additional/engineered assembly processes. Molecular dynamics simulations provided insights into the structural states of the hydrophobic building blocks during assembly and mechanism of film formation. Furthermore, the hydrophobic MPNs facilitated the preparation of fluorescent‐labeled and bioactive capsules through postfunctionalization and also particle–cell association engineering by controlling the hydrophobicity of the building blocks. Engineering MPN particle systems via building block hydrophobicity is expected to expand their use. [ABSTRACT FROM AUTHOR]

Tailoring the hydrophobicity of supramolecular assembly building blocks enables the fabrication of well‐defined functional materials. However, the selection of building blocks used in the assembly of metal–phenolic networks (MPNs), an emerging supramolecular assembly platform for particle engineering, has been essentially limited to hydrophilic molecules. Herein, we synthesized and applied biscatechol‐functionalized hydrophobic polymers (poly(methyl acrylate) (PMA) and poly(butyl acrylate) (PBA)) as building blocks to engineer MPN particle systems (particles and capsules). Our method allowed control over the shell thickness (e.g. between 10 and 21 nm), stiffness (e.g. from 10 to 126 mN m−1), and permeability (e.g. 28–72 % capsules were permeable to 500 kDa fluorescein isothiocyanate‐dextran) of the MPN capsules by selection of the hydrophobic polymer building blocks (PMA or PBA) and by controlling the polymer concentration in the MPN assembly solution (0.25–2.0 mM) without additional/engineered assembly processes. Molecular dynamics simulations provided insights into the structural states of the hydrophobic building blocks during assembly and mechanism of film formation. Furthermore, the hydrophobic MPNs facilitated the preparation of fluorescent‐labeled and bioactive capsules through postfunctionalization and also particle–cell association engineering by controlling the hydrophobicity of the building blocks. Engineering MPN particle systems via building block hydrophobicity is expected to expand their use. [ABSTRACT FROM AUTHOR]

Polymer composites with high dielectric constant and minimal dielectric losses have wide ranging prospects for advanced applications in the flexible electronics and electrical industry. In this study, we used the advantages of carbonaceous hybrid nanofillers to develop a flexible dielectric material. Herein, a set of hybrid nanocomposites were successfully fabricated by incorporating the Ti3C2Tx (MXene) and MWCNTs (multi‐walled carbon nanotubes) hybrid mixture as the conductive moiety into the poly(ethylene‐co‐methyl acrylate) (EMA)/ethylene‐octene co‐polymer (EOC) binary blend as the matrices using solution mixing technique followed by compression molding. As prepared, EMA/EOC/Ti3C2Tx/MWCNTs hybrid composites have been characterized by FTIR (Fourier transform infrared) spectroscopy, XRD (X‐ray diffraction), TGA (thermogravimetric analysis), FESEM (field emission scanning electron microscopy), and DSC (differential scanning calorimetry). We studied the effects of Ti3C2Tx and MWCNTs contents in the hybrid composites on the thermal, dielectric, and electrical properties. Among all the 15 wt% hybrid mixture containing 2 wt% MWCNTs loaded composite has the highest dielectric constant (ℇr = 122.21) and the lowest dissipation loss (tan δ = 0.030) at 100 Hz. The present studies recommend the EMA/EOC/Ti3C2Tx/MWCNTs hybrid composites can be used in smart and flexible electronic storage material. Highlights: EMA‐EOC blend composites with hybrid Ti3C2Tx/MWCNTs were processed.2.5 wt% MWCNTs loaded hybrid composite shows excellent thermal stability.Composite with 2 wt% MWCNTs has ℇ' = 122.21 and tanδ = 0.03 at 100 Hz.2.5 wt% MWCNTs composite has electrical conductivity of 3.26 × 10−8 Ω−1 m−1.This composite can be used in smart and flexible electronic storage material. [ABSTRACT FROM AUTHOR]

Glycerol is produced in large quantities as a co‐product in the manufacturing of biodiesel and has received relatively little attention as a substrate for carbon−carbon bond‐forming reactions. In this work, the photocatalyzed reaction between glycerol and electron‐deficient olefins is investigated to regioselectively insert an alkyl group at C2 in the triol. The results show that the transformation is highly dependent on the nature of the photocatalyst and the olefin. In the presence of an iridium catalyst and quinuclidine, glycerol can be coupled at C2 with sterically unhindered acrylates. In the presence of tetrabutylammonium decatungstate, glycerol can be reacted with fumaronitrile, N‐methyl maleimide, methyl acrylate and itaconic anhydride where the latter two substrates require the additional presence of potassium persulfate as an oxidant. These findings give rise to several new carbon−carbon bond‐forming reactions with glycerol that allow the triol to be converted into more elaborate structures. [ABSTRACT FROM AUTHOR]

Polymer nanocomposites have garnered significant interest for electromagnetic interference (EMI) shielding applications due to their lightweight, anticorrosive and tunable properties. Employing the solution blending technique, we have developed a composite material comprising an 80wt% EMA (Ethylene–Methyl Acrylate) and 20wt% TPO (Thermoplastic Polyolefin) co-continuous blend. The incorporation of Reduced Graphene Oxide (RGO) as a conductive filler is achieved through precise confinement within the EMA phase of the polymer matrix. The selective placement of the RGO nanosheets within the EMA phase results in a dual percolation phenomenon, significantly lowering the electrical percolation threshold. A notable EMI SE value of -29.66 dB and electrical conductivity of 10–3 S/cm is acheived with the addition of 5wt% RGO. Further optimizing the composite, a loading of 15wt% RGO showcases an outstanding EMI SE of -39.06 dB. Moreover, this composite demonstrates commendable thermal conductivity of 0.75 W/m.K, alongside promising mechanical properties. The findings offer a promising avenue for the integration of this material in EMI-sensitive applications, particularly in the realms of stretchable and wearable electronics, offering effective thermal management and proficient microwave shielding capabilities. [ABSTRACT FROM AUTHOR]

In this study, for the first time, we investigate cobalt-mediated radical block copolymerization of vinyl acetate (VAc) and methyl acrylate (MA) in a packed column system in the presence of cobalt(II) acetylacetonate (Co (acac)2) as a controlling agent. This copolymerization system has the capability to remove the residual catalyst and separate copolymers with different molecular weights, simultaneous to polymerization. Synthesis of high-purity poly (vinyl acetate)-b-poly(methyl acrylate-co-vinyl acctate) (PVAc-b-P(MA-co-VAc)) copolymers were successfully performed by initiating the radical copolymerization of MA and VAc from PVAc-Co (acac)2 macroinitiator in the packed column with silica gel particles. Copolymerization reaction proceeds via a controlled characteristic with first-order kinetics with respect to monomers, predetermined molecular weight, and relatively narrow molecular weight distribution. GPC, 1HNMR, and DSC analyses demonstrated that the PVAc-b-P(MA-co-VAc) was formed with a blocky structure. Based on the analyses, it was found that the VAc content in the block copolymer progressively increased with increasing conversion in the constant VAc initial ratio, indicating that the second block copolymer had a gradient sequence distribution. Moreover, the VAc and MA reactivity ratios in the packed column with silica gel particles were calculated using the extended Kelen–Tudos method to be rMA = 4.98 and rVAc = 0.62, respectively. [ABSTRACT FROM AUTHOR]

Concrete is vital for the development of modern buildings. However, they suffer from the high viscosity problem in their application process due to the use of a low water–cement ratio in order to maintain their high strength. Developing PCEs with the presence of ester functional groups in their molecular structure is one of the most effective measures to improve the flowability of concrete. Here, three PCEs with different alkyl densities of acrylic acid ester: PCE-M, PCE-E, and PCE-B were designed to explore their viscosity-reducing effect on the performance of cement and concrete. The structures of the three PCEs were characterized via Fourier transform infrared (FTIR) spectra, proton nuclear magnetic resonance (1H NMR), and gel permeation chromatography (GPC). Their properties were also determined via zeta potential, surface tension, and rheological experiments. It was found that PCE-M had the best performance, with the lowest surface tension, highest zeta potential, and therefore highest charge density on the cement particles, lowest viscosity, and highest flowability of cement paste, and exhibited the best performance of concrete in terms of workability. The best performance of PCE-M in reducing the viscosity of cement and concrete can be ascribed to the smallest amount of water-repellent alkyl groups, enhancing the electrostatic repulsion and reducing the viscosity, thereby boosting the dispersion and stabilization of cement pastes and concrete. This study shed lights on designing other PCEs with high viscosity-reducing effects via an ester group control. [ABSTRACT FROM AUTHOR]

Improving water-based polymer's properties using silicon compounds is strongly noticed nowadays. A novel siloxane-based crosslink agent was synthesized using oligomeric polydimethylsiloxane (PDMS) hydroxyl-terminated. The crosslinker was used for emulsion copolymerization of methyl methacrylate (MMA), butyl acrylate (BA), and acrylic acid (AA). Incorporation of the crosslinker in the structure of the copolymer increased the average latex particle size (from about 165 to 207 nm) and as a result, the viscosity of the latexes was dramatically decreased (from 212 cP to 83 cP). The crosslink density of the latexes, meanwhile, was raised (from about 7–60%). Electrostatic stability of the latexes was improved in the presence of the crosslinker (zeta potential from − 31.7 mV to -49.5 mV and the average mobility of the latexes particles from − 2.4 μm/s/V/cm to -3.8 μm/s/V/cm). The crosslinking agent affected both the initial decomposition temperature and residual weight fraction of the copolymer (from 353 to 406 °C and from about 0.5 w% to 12.4 w% respectively). A morphological study of the latexes was carried out using transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM) techniques. The addition of the crosslinker, led to a decrease in the contact angle (from 70 to 39 degrees) of the latexes film formed. [ABSTRACT FROM AUTHOR]

The copolymerization of methyl acrylate (MA) and glycidyl methacrylate (GMA) with 1-hexene was carried out using activator regenerator by electron transfer atom transfer radical polymerization (ARGET ATRP) employing Cu(0)/CuBr2 as a catalyst, pentamethyl diethylenetriamine (PMDETA) as a ligand, and ethyl 2-bromoisopropionate (EBriP) as the initiator, all at a reaction temperature of 70°C. This process resulted in the production of viscous and transparent copolymers, namely poly (methyl acrylate-co-1-hexene) or PMH and poly (glycidyl methacrylateco-1-hexene) or PGMH. For the MA/1-Hex copolymer, conversion rates ranged from a maximum of 31 wt.% to a minimum of 12 wt.%, while the GMA/1-hexene copolymer exhibited conversion rates ranging from a maximum of 42 wt.% to a minimum of 12 wt.%. It was observed that increasing the amount of 1-hexene during the synthesis led to a higher incorporation of 1-hexene content in both the MA and GMA polymer backbones, with a maximum of 15 wt.% and 18 wt.% of 1-hexene being incorporated into PMH and PGMH, respectively. The incorporation of 1-hexene was confirmed through Nuclear Magnetic Resonance (NMR) studies, including 1H, 13C, and DEPT 135 studies. Additionally, the copolymer PMH and PGMH exhibited monomodal molecular weight distribution curves when evaluated using the size exclusion chromatography (SEC) high-performance liquid chromatography (HPLC) technique, with polydispersity values in the range of 1.19-1.37 and 1.07-1.11, respectively. These findings indicate that the copolymerization process was well-controlled and followed a radical polymerization mechanism. [ABSTRACT FROM AUTHOR]

Photoswitchable fluorescent polymers (PFPs) are emerging as a class of promising systems for photowritable pattern, optical anti‐counterfeiting, and information encryption. They typically use harmful UV light as the stimulus, which often leads to inevitable photobleaching and poor reversibility. To address this issue, visible‐light‐driven PFPs by copolymerization of novel negative photochromic spiropyran monomer and methyl acrylate are developed. The obtained copolymers display bright red fluorescence, which can be reversibly turned off by visible light irradiation. Many appealing features are observed in this system, including fast photo‐responsibility, prominent photo‐reversibility and photostability, simple preparation process, and processability. Their applications in photorewritable patterns, optical anti‐counterfeiting, and information encryption are also demonstrated. [ABSTRACT FROM AUTHOR]

Fluorinated polymers are receiving more and more attention worldwide due to their unique chemical properties, and modified fluorinated polymers with different topologies are persued for enriching and enhancing their performance in a variety of application fields. In this work, main-chain-type semifluorinated graft copolymers are produced steadily in continuous tube reactors via photocontrolled step transfer-addition and radical-termination (START) polymerization and Cu(0)-mediated reversible deactivation radical polymerization (Cu(0)-RDRP) at room temperature for the first time. Specifically, semifluorinated alternating copolymer (AB)nB is prepared by START polymerization of 1,6-diiodoperfluorohexane (A) and 1,7-octadiene (B) in the first quartz pipeline under irradiation with purple LED light at 20 °C. The (AB)nB with periodic C-I bonds is then flowed into the second copper pipeline directly and acts as the macroinitiators for Cu(0)-RDRP of methyl acrylate (MA) to obtain corresponding graft copolymer (AB)nB-g-PMA. This work provides a new strategy for continuous synthesis of fluorinated graft copolymer materials. [ABSTRACT FROM AUTHOR]

The behavior of tin based copper alloy in sea water was studied by immersion of alloy samples in sea water for six months. The samples were inspected by stereo microscope and the corrosion behavior was evaluated by mass loss, scanning electron microscopy SEM and electrochemical impedance EIS spectroscopy techniques. Nano ethyl methacrylate-methyl acrylate (EMAMA) copolymer coating was applied to protect the copper alloy from corrosion. The efficiency of using nano EMAMA copolymer coating for protection of copper alloy from corrosion was tested by electrochemical impedance EIS spectroscopy technique. The nano structured EMAMA copolymer film resulted in the formation of a structure that can act as a barrier layer from corrosion. Exposure of the tin based copper alloy samples with and without the EMAMA copolymer coating to sodium chloride solution led to a remarkable inhibition of corrosion for the coated samples only. The inhibition efficiency obtained from samples coated with EMAMA copolymer coatings revealed the very high protection efficiency reaching 98.0% during six months of exposure. The durability of the film formed by EMAMA copolymer coating was tested and found to be 0.98. [ABSTRACT FROM AUTHOR]

We have prepared a ligand library based on a ferrocenyl aziridinyl methanol core unit (simply called FAM) having a phenyl group, a cyclohexyl group, and a naphthyl group to be used in 1,3‐dipolar cycloaddition (1,3‐DC) reactions for the synthesis of chiral pyrrolidines. These chiral ligands were used with AgOAc in 1,3‐DC reactions taking place between the aryl‐substituted azomethine ylides and N‐methylmaleimide as the dipolarophile. In each case, the expected aryl‐substituted pyrrolidines were obtained in good to excellent yields with acceptable enantioselectivities favoring only the endo product. The chiral catalyst system CFAM4–AgOAc was also used in 1,3‐DC reaction with different dipolarophiles such as dimethyl maleate, tert‐butyl acrylate, methyl acrylate, trans‐chalcone, and vinyl sulfone. In each case, the cycloadducts were obtained in acceptable yields albeit with low ee. Fortunately, it was possible to increase the ee up to >99% upon crystallization. [ABSTRACT FROM AUTHOR]

The effect of titanium dioxide (TiO2) on the thermal properties, morphology, intermolecular interactions, and dielectric response of poly(ethylene oxide)/poly(methyl acrylate) (PEO/PMA) polymer electrolytes was studied. These properties were elucidated based on the empirical point of view through systematic sample characterization using differential scanning calorimetry (DSC), polarized optical microscopy (POM), Fourier-transform infrared (FTIR) spectroscopy and impedance spectroscopy (IS). Without TiO2, lithium perchlorate preferably dissolves in the PEO phase rather than in the PMA phase. When TiO2 is added into PEO/PMA/salt systems, TiO2 shows weak interactions either with PEO or PMA phase. The addition of TiO2 changes the morphology of PEO/PMA systems with or without salt from a homogeneous mixture to a heterogeneous mixture displayed by the presence of two Tgs and through the morphological study. The conductivity of both PEO/PMA with and without salt systems remains constant upon the addition of TiO2. Hence, the presented data here have shown that TiO2 provides only a minor effect on the properties of PEO/PMA with and without salt systems. Indirectly, it shows by adding TiO2 under this experimental study may not bring a significant contribution to the improvement of polymer electrolytes. [ABSTRACT FROM AUTHOR]

Copper methoxide compound IPrCuOMe was unexpectedly formed in a reaction of IPrCuPPh2 with methyl acrylate. The alkoxide product was identified from the reaction mixture spectroscopically and structurally characterized. This C–O bond cleavage reaction likely depends on nucleophilicity of the Cu–P bond of IPrCuPPh2. [ABSTRACT FROM AUTHOR]

Mixed 18% solutions of cellulose and PAN terpolymer containing methyl acrylate and methylsulfonate comonomers in N-methylmorpholine-N-oxide have been obtained over the entire range of compositions. All the obtained systems based on cellulose and PAN are biphasic, and the morphological features of the emulsions change from highly dispersed isotropic to fibrillar depending on the phase composition and the intensity of the deformation effect. At high shear stresses that emerge during preparation of the solutions in an extruder, all emulsions are characterized by the same microheterogeneous morphology, which is transformed into fibrillar by deformation. An IR spectroscopic study has established that in the preparation process, specific interactions occur between the functional groups of macromolecules of the cocomponents, leading to the formation of PAN/cellulose associates, which undergo hydrophobic repulsion along the interfaces. It is this process that initiates the fibrillation of the cellulose solution phase in the presence of a PAN solution during deformation. The rheological behavior of mixed solutions over the entire range of concentrations in continuous and dynamic modes at temperatures of 110–130°C is a direct consequence of the phase composition and morphological transformations occurring during deformation. Emulsion compositions characterized by viscoelastic properties that make it possible to successfully form composite fibers have been chosen. [ABSTRACT FROM AUTHOR]

Attaining nanocomposites having high mechanical and electrical properties simultaneously via carbon based nanomaterials remains exciting as carbon nanomaterial have a pattern of formation of random dispersive networks in polymeric nanocomposites. Here, polycarbonate/ethylene methyl acrylate blend (PC/EMA) nanocomposites were fabricated using graphene to explore their effect on electrical, mechanical, and electromagnetic interference (EMI) shielding properties. The mechanical properties of the nanocomposites are improved by enhancing the graphene content. EMI shielding properties of graphene based composites were calculated in X band. The fabricated PC/EMA-graphene nanocomposites showed an EMI shielding of -51 dB for 15 phr graphene loading. Thus, the excellent EMI shielding performance and sensitive response combination make the nanocomposites promising material for many potential applications in next-generation electronics. [ABSTRACT FROM AUTHOR]

Polyacrylate-based network materials are widely used in various products owing to their facile synthesis via radical polymerization reactions. In this study, the effects of alkyl ester chains on the toughness of polyacrylate-based network materials were investigated. Polymer networks were fabricated via the radical polymerization of methyl acrylate (MA), ethyl acrylate (EA), and butyl acrylate (BA) in the presence of 1,4-butanediol diacrylate as a crosslinker. Differential scanning calorimetry and rheological measurements revealed that the toughness of MA-based networks drastically increased compared with that of EA- and BA-based networks; the fracture energy of the MA-based network was approximately 10 and 100 times greater than that of EA and BA, respectively. The high fracture energy was attributed to the glass transition temperature of the MA-based network (close to room temperature), resulting in large energy dissipation via viscosity. Our results set a new basis for expanding the applications of polyacrylate-based networks as functional materials. [ABSTRACT FROM AUTHOR]

A series of siloxane-functionalized vanadium phosphorus oxide (VPO)-TiO2 catalysts were prepared by a wet-solid mechanochemical method and used to catalyze the co-activation reaction of aldehyde condensation with esterification, a novel route to significantly reduce carbon deposition and stably, efficiently, sustainably prepare methyl acrylate and acrylic acid. [ABSTRACT FROM AUTHOR]

Solvents constitute around 80% of the total volume of chemicals used in fine-chemical processes and contribute significantly to their environmental impact and hazard profile. Thus, there is a strong driving force towards the replacement of traditional fossil-based solvents by alternatives that are more benign in terms of their origin, availability, convenience of synthesis, handling, biodegradability and environmental impact. In the class of polar aprotic solvents, the most successful "green" replacement is γ-valerolactone (GVL). Here, we propose the use of a structurally related compound, 5-methyl-1,3-dioxolane-4-one (LA-H,H), as a reaction medium. It is easily prepared from lactic acid and formaldehyde and satisfies the criteria for a green solvent. It is stable under neutral or basic conditions. Despite the presence of a ketal functionality, it even survives mildly acidic conditions. Evaluation of the Kamlet–Taft and Hansen solvent parameters shows that indeed LA-H,H and GVL are closely similar, suggesting that LA-H,H is an effective new green entry in the class of polar aprotic solvents. We have tested its performance in Pd-catalyzed Heck arylation of methyl acrylate and in the Menschutkin reaction of N-methylimidazole with 1-iodobutane. LA-H,H is also the parent of a whole family of potential solvents easily prepared from two green precursors: α-hydroxy carboxylic acids (lactic, mandelic, and α-hydroxyisobutyric acids) and aldehydes/ketones (formaldehyde, acetaldehyde, and acetone); five such variations were briefly examined. Interestingly, LA-H,H has the unusual property of forming a three-phase system when combined with water and hexane, which may allow technological variations that are not possible with the more normal one- and two-phase systems. As a curiosity, a rare four-phase system is achievable combining LA-H,H with octane, water and perfluorodecaline. [ABSTRACT FROM AUTHOR]

Coagulative nucleation in the copolymerization of methyl methacrylate–butyl acrylate (MMA-BA) via semicontinuous emulsion heterophase polymerization (SEHP) under monomer-starved conditions in latexes with high solid content (50.0 wt %) and low concentrations of surfactant is reported. The SEHP technique allows the obtention of latex with high colloidal stability and has potential industrial application in polymer synthesis. High instantaneous conversions (>90%) and a high-ratio polymerization rate/addition rate (Rp/Ra) ≥ 0.9 were obtained at low times until the final copolymerization, which confirmed the starved conditions in the systems at the highest surfactant concentrations. The particle size exhibited a linear size increment at conversions between 0 and 40% induced by homogeneous nucleation, a transition region between 40 and 50%, and non-linear behavior at higher conversions by coagulative nucleation. These three behaviors were also observed in the particle surfactant coverage area (Sc), Z-potential, particle coagulation rate (dNp/dt) by the Smoluchowski model, final particle size (Dpz), and number particle (Np) through the reaction. By means of transmission electron microscopy (TEM) images, the onset of coagulation was observed from 50% of conversion until the end of the reaction. In addition, in both processes of copolymerization, tacticity was displayed (mainly syndiotacticity). [ABSTRACT FROM AUTHOR]

The one-pot synthesis of N-substituted α,β-dehydrotyrosyl dipeptides was carried out by the azlactone method. The target dipeptides were obtained in good yields (53–79%). From the latter, 2,3,5-trisubstituted 4-imidazolones were obtained using 1,1,1,3,3,3-hexamethyldisilazane as a dehydrating agent. It was found that in the case of β-alanine-containing peptides, abstraction of the methyl ester of acrylic acid and the formation of 2,5-disubstituted 4-imidazoline were observed. Antiradical and anticholinesterase properties of the synthesized compounds were studied. Docking analysis was carried out for both some dipeptides and imidazole-4-ones. [ABSTRACT FROM AUTHOR]

Rationale: Synthesis of copolymer is one of the major approaches to establish sophisticated polymers. In copolymer analysis in mass spectrometry (MS), an increase in the number of monomer unit species and/or the polymer molecular weight results in complex mass spectra, and a method is required to solve this problem. Methods: In this study, electrospray ionization‐ion mobility spectrometry‐mass spectrometry was employed to analyze styrene/methyl methacrylate/n‐butyl acrylate (St/MMA/nBA) terpolymers via Kendrick mass defect (KMD) analysis. An expanded Fourier transform‐based noise reduction method for the copolymer was developed to improve the decrease in the signal/noise ratio observed in the higher m/z region. Results: Low‐mass terpolymers (0.7 kDa) were identified by comparing the observed and theoretical results using a two‐dimensional KMD plot. For the 1.5 kDa terpolymer, the signal overlap, of which KMD value was not matched with the theoretical one, was interpreted by the shift from the theoretical value in the KMD plot. For the 3.0 kDa terpolymers, the compositional candidates were determined by the prediction based on the compositional information of low‐mass terpolymers previously analyzed. The 4.5 kDa terpolymer was interpreted after the expanded noise filtering. Conclusions: The terpolymers, whose molecular weight was up to 4.5 kDa, were successfully characterized at a molecular level. The dependency of the St/MMA/nBA composition on molecular weight was observed; that is, the nBA content decreased with an increase in the molecular weight. [ABSTRACT FROM AUTHOR]

We report a versatile mechanophore exhibiting a vividly detectable, light‐regulable multicolor mechanochromism. Such optical features rely on the synergistic coupling of mechanochromic bis‐rhodamine (Rh) and photochromic bisthienylethene (BTE). Poly(methyl acrylate)s incorporating this bis‐mechanophore can be mechanically activated under sonication. The relative distribution of the two distinctly colored and fluorescent Rh ring‐opening products is altered with different magnitudes of applied force. Orthogonal use of the photochromic reaction of the BTE core can strengthen the mechanochromism and gate the mechanofluorescence in polymers. Due to increased conjugation offered by the BTE linker, both force‐ and light‐induced optical signals display high contrast. Combined DFT simulated and experimental results reveal that the three subunits (two Rhs and one BTE) in this chromophore are activated sequentially, thus generating switchable three‐colored forms and gradient optical responses. [ABSTRACT FROM AUTHOR]

We report a versatile mechanophore exhibiting a vividly detectable, light‐regulable multicolor mechanochromism. Such optical features rely on the synergistic coupling of mechanochromic bis‐rhodamine (Rh) and photochromic bisthienylethene (BTE). Poly(methyl acrylate)s incorporating this bis‐mechanophore can be mechanically activated under sonication. The relative distribution of the two distinctly colored and fluorescent Rh ring‐opening products is altered with different magnitudes of applied force. Orthogonal use of the photochromic reaction of the BTE core can strengthen the mechanochromism and gate the mechanofluorescence in polymers. Due to increased conjugation offered by the BTE linker, both force‐ and light‐induced optical signals display high contrast. Combined DFT simulated and experimental results reveal that the three subunits (two Rhs and one BTE) in this chromophore are activated sequentially, thus generating switchable three‐colored forms and gradient optical responses. [ABSTRACT FROM AUTHOR]

To minimize radiation pollution at ultra‐low filler concentrations, there is a growing interest in microwave‐absorbing materials based on polymer blends composites. Herein, ethylene‐co‐methyl acrylate (EMA)/thermoplastic polyolefin (TPO) blend composites were prepared by employing solution mixing utilizing conductive Vulcan XC 72 carbon black (VCB) as nanofiller. The work focused on the reduction of electrical percolation and outstanding electromagnetic interference (EMI) shielding performance in low loading caused by the preferential distribution of carbon particles in one phase (ethylene‐co‐methyl acrylate copolymer) of the co‐continuous immiscible polymer blend. The fabricated conductive blend was further tested to ensure its superiority in physic‐mechanical and thermal stability. The morphology analysis reveals that the VCB particles are selectively localized in EMA phase of the blend which facilitates the formation of compact spatial conductive network throughout the matrix for electronic hopping. High electrical conductivity is achieved in the scale 10−2 S/cm for the prepared composites with 30 wt% of carbon black loading whereas a total EMI shielding effectiveness of −29 dB and thermal conductivity of ~0.75 W/m·K are achieved for this same filler content. This study reveals that the fabricated conductive polymer nanocomposites can be effectively utilized as promising EMI shields in the future generation of stretchable and wearable electronics. [ABSTRACT FROM AUTHOR]

A new rotationally hindered diphosphoramidite ligand has been applied to the Rh-catalyzed hydroformylation of various olefins. Good activity as well as excellent regioselectivity toward the formation of linear aldehydes were achieved. Remarkable performances were also observed in the hydroformylation of functionalized olefins, including methyl acrylate, allyl acetate, crotonaldehyde ethylene acetal and styrene. [ABSTRACT FROM AUTHOR]

The condensation of formaldehyde and acetic acid to acrylic acid (AA) is considered as one of the important routes for the clean and high value utilization of coal-based methanol derivatives. Herein, we successfully synthesized environment-friendly NASICON catalysts using Ti(SO4)2 as the titanium source. With guaranteed high selectivity (∼78%), the space time yield of AA + MA (methyl acrylate) can be up to 123.9 μmol g−1 min−1, far higher than the results reported previously. Based on the characterizations, it is demonstrated that the modulation of the acidic and basic properties (including distribution, ratio of B/L, etc.) led by the specific elemental and hybrid TiP2O7 phase plays crucial roles in catalyst supremacy. [ABSTRACT FROM AUTHOR]

Morita Baylis‐Hillman (MBH) reaction of various aldehydes, bearing electron‐releasing as well as electron‐withdrawing groups with acrylonitrile and methyl acrylate as electron‐deficient alkene is reported herein. The cornerstone of the reaction is the utilization of EDC.HCl (a salt) as a novel catalyst, salt gets converted into neutral tertiary amine in the presence of CuI for the synthesis of MBH adduct. Excellent product yield (up to 99 %), ambient reaction conditions, shorter reaction time, and no side product formation are the salient features of the envisaged synthetic protocol. [ABSTRACT FROM AUTHOR]

Incorporation of photolabile moieties into the polymer backbone holds promise to remotely‐control polymer degradation. However, suitable synthetic avenues are limited, especially for radical polymerizations. Here we report a strategy to program photodegradability into vinylic polymers by exploiting the wavelength selectivity of photocycloadditions for radical ring‐opening polymerization (rROP). Irradiation of coumarin terminated allylic sulfides with UVA light initiated intramolecular [2+2] photocycloaddition producing cyclic macromonomers. Subsequent RAFT‐mediated rROP with methyl acrylate yielded copolymers that inherited the photoreactivity of the cyclic parent monomer. Irradiation with UVB initiated efficient photocycloreversion of the coumarin dimers, causing polymer degradation within minutes under UVB light or days under sunlight exposure. Our synthetic strategy may pave the way to insert photolabile linkages into vinylic polymers, tuning degradation for specific wavelengths. [ABSTRACT FROM AUTHOR]

The synthesis of polar functionalized cyclic olefin copolymers (COCs) from the coordination copolymerization of norbornene (NB) and polar monomers catalyzed by late transition metal catalysts has been a recent research hotspot. However, few catalysts have achieved efficient copolymerization with commercial vinyl-type polar monomers, such as methyl acrylate (MA). In this contribution, nickel complexes bearing 2-(diarylphosphino)-N-phenylbenzenamine ligands were synthesized and applied as pre-catalysts to catalyze the (co)polymerization of norbornene. Upon the activation of methylaluminoxane (MAO), these nickel catalysts were active for norbornene polymerization with the highest activity achieved being 3.6 × 106 g mol−1 h−1 and the highest number average molecular weight (Mn) of polynorbornene (PNB) reaching 27.4 × 105 g mol−1. Moreover, these nickel catalysts also promoted the copolymerization of norbornene and MA to furnish high-molecular-weight NB/MA copolymers (Mn up to 6.20 × 104 g mol−1) with reasonable MA contents (3.07−5.90 mol%). The molecular weight of PNB and NB/MA copolymers obtained by the present nickel catalysts are remarkably higher than those of the (co)polymers from our previous reported dimethyl substituted phosphinobenzenamine nickel catalyst, suggesting significant progress in this field. [ABSTRACT FROM AUTHOR]

Incorporation of photolabile moieties into the polymer backbone holds promise to remotely‐control polymer degradation. However, suitable synthetic avenues are limited, especially for radical polymerizations. Here we report a strategy to program photodegradability into vinylic polymers by exploiting the wavelength selectivity of photocycloadditions for radical ring‐opening polymerization (rROP). Irradiation of coumarin terminated allylic sulfides with UVA light initiated intramolecular [2+2] photocycloaddition producing cyclic macromonomers. Subsequent RAFT‐mediated rROP with methyl acrylate yielded copolymers that inherited the photoreactivity of the cyclic parent monomer. Irradiation with UVB initiated efficient photocycloreversion of the coumarin dimers, causing polymer degradation within minutes under UVB light or days under sunlight exposure. Our synthetic strategy may pave the way to insert photolabile linkages into vinylic polymers, tuning degradation for specific wavelengths. [ABSTRACT FROM AUTHOR]

A convenient domino synthetic approach for the construction of the indolizidine core in diastereoselective manner has been developed from inexpensive starting compounds, providing triple functionalization. The novel synthetic route started from β-lactam derived from 1,5-cyclooctadiene including a ring-opening metathesis/cross-metathesis sequence as key steps with methyl acrylate followed by intramolecular ring closure across an aza-Michael addition. The process gave functionalized indolizidine framework with stereocontrol in high yields. DFT calculations supported the experimentally observed stereoselective reaction. [ABSTRACT FROM AUTHOR]

The synthetic polymer industry is transitioning from the use of organic solvents to aqueous media in order to reduce environmental impact. However, with radical polymerization kinetics affected by hydrogen-bonding solvents, there is limited information regarding the use of water as a solvent for sparingly soluble monomers. Thus, in this paper, the radical polymerization of methyl acrylate (MA) and N-tert-butylacrylamide (t-BuAAm) is studied in water and ethanol (EtOH), as the copolymer product is of commercial interest. A series of semi-batch reactions are conducted under a range of operating conditions (i.e., reaction temperature, solvent-to-monomer ratio, and comonomer composition) to demonstrate that the copolymer can be successfully synthesized without significant drifts in product molar masses or composition. The experiments provide additional data to probe the influence of the solvent on the polymerization rate and copolymer properties, as the low monomer concentration maintained under starved-feed operation leads to a solvent-to-monomer ratio different from that in a batch system. A model that captures the influence of backbiting and solvent effects on rate, previously developed and tested against batch polymerizations, also provides an excellent description of semi-batch operation, validating the set of mechanisms and kinetic coefficients developed to represent the system. [ABSTRACT FROM AUTHOR]

The radical homopolymerization of N‐tert‐butyl acrylamide (t‐BuAAm) and its copolymerization with methyl acrylate (MA) is studied in ethanol/water solutions over a range of initial monomer and initiator levels between 50 and 70 °C. While short‐chain branching for poly(t‐BuAAm) samples could not be detected by 13C NMR, the reduced rate of monomer conversion with lowered monomer content indicates the formation of mid‐chain radicals (MCR) by backbiting. Adding water as a cosolvent to ethanol significantly increases reaction rates, in agreement with recent pulsed‐laser studies that quantify the influence of solvent composition on homopropagation kinetics. However, the measured drifts in comonomer composition with conversion are well represented by a single pair of reactivity ratios (rMA = 1.12 ± 0.01, rt‐BuAAm = 0.71 ± 0.01) over the complete range of experimental conditions. A mechanistic model developed to describe t‐BuAAm homopolymerization is extended to capture the impact of reaction operating conditions (monomer content and composition, solvent composition, initiator content, and temperature) on the features of t‐BuAAm/MA copolymerization, thus providing a tool for product and process optimization. The model structure can be used to support the development of other acrylate/acrylamide systems as part of the continued efforts to utilize "green" solvents to reduce the environmental impacts of polymerization processes. [ABSTRACT FROM AUTHOR]

The novel PAMAM perylene tetracarboxydiimide 5 was synthesized via PAMAM divergent strategy, involves initial Michael addition of aminofunctional core 3 with methyl acrylate followed by exhaustive amidation of the resulting ester 4 with a large excess of ethylenediamine to afford the fluorescent dendrimer 5 with reactive amine groups of its periphery, The chosen fluorophore units are suitable donor–acceptor pair for light-harvesting materials which was in agreement with their good antibacterial activity. [ABSTRACT FROM AUTHOR]

Unprotected 6,7‐benzotropolone and bromine were known to undergo an electrophilic substitution delivering the 7‐bromo derivative; it was carried on as its methyl ether. O‐Acetyl‐6,7‐benzotropolone added bromine at the C8=C9 bond whereupon an amine‐induced E1cb elimination led to the 8‐brominated benzotropolone acetate; ester cleavage with aqueous acetic acid and etherification with diazomethane delivered the corresponding methyl ether. O‐Methylbenzotropolone was brominated with N‐bromosuccinimide giving the 9‐brominated methyl ether. The mentioned bromobenzotropolone methyl ethers underwent Pd‐catalyzed C−C and C−B couplings. They comprised Suzuki‐Miyaura couplings (with R−BF3K, R=Me, Bu, vinyl, Ph), Negishi couplings (with BuZnCl), Sonogashira couplings (with HC≡C−R, R=SiMe3, CH2OH, Ph, Bu), Mizoroki‐Heck reactions (with methyl acrylate, methyl vinyl ketone, styrene, 3‐buten‐2‐ol), a carbonylative coupling, and Suzuki‐Miyaura borylations (with B2Pin2). Subsequent O‐demethylations with BCl3 succeeded in most cases; they furnished a library of 34 O‐unprotected Br‐free benzotropolones, 31 of which were unknown before. [ABSTRACT FROM AUTHOR]

In this study, a series of Ni10MoxAl composite metal oxide (Ni10MoxAl, NiO = 10 wt.%, x = 2.5, 5, 10, 15, 20 wt.%) catalysts with different Mo content were prepared by a solvothermal method using a water—ethanol system. By employing various characterization technologies, it was confirmed that the suitable amount of the Mo element can not only promote the dispersion of the Ni species but also inhibit the formation of the inactive NiAl2O4 phase. Consequently, the hydrogenation activity of the Ni10MoxAl catalysts was affected by the particle size of the active components and the amount of the NiAl2O4 phase. As a result, the Ni10Mo10Al catalyst showed the best catalytic performance on methyl acrylate hydrogenation, and the yield of methyl propionate can be increased from 53.7% to 89.5% at 100 °C and 1 MP H2, compared with the Ni10Mo10/γ–Al2O3 catalyst prepared by a traditional impregnation method. The stability of the Ni10Mo10Al catalyst was also investigated, and the catalyst can run stably for 23 h. The novel strategy adopted in this article provides a new direction for the preparation of high activity Ni–Mo catalysts. [ABSTRACT FROM AUTHOR]

Methyl acrylate (MA) and ethyl acrylate (EA) had previously tested positive for mutagenicity in vitro, but in vivo studies were negative. One of the metabolism pathways of alkyl acrylates is conjugation with glutathione. The glutathione availability is restricted in standard in vitro test systems so that they do not reflect the in vivo metabolism in this respect. We investigated whether the addition of glutathione to the in vitro L5178Y/TK+/− mouse lymphoma mutagenicity test prevents alkyl acrylate's mutagenicity in vitro. We also investigated whether the quantitative relationships support the notion that the GSH supplemented in vitro systems reflect the true in vivo activity. Indeed, glutathione concentrations as low as 1 mM completely negate the mutagenicity of MA and EA in the L5178Y/TK+/− mouse lymphoma mutagenicity test up to the highest concentrations of the two acrylates tested, 35 µg/ml, a higher concentration than that previously found to be mutagenic in this test (14 µg MA/ml and 20 µg EA/ml). 1 mM Glutathione reduced the residual MA and EA at the end of the exposure period in the mutagenicity tests by 96–97%, but in vivo up to 100 mg/kg body weight MA and EA left the glutathione levels in the mouse liver and forestomach completely intact. It is concluded that the in-situ levels of glutathione, 7.55 ± 0.57 and 2.84 ± 0.22 µmol/g mouse liver and forestomach, respectively, can efficiently protect against MA and EA-induced mutagenicity up to the high concentration of 100 mg MA and EA/kg body weight and that the negative in vivo mutagenicity tests on MA and EA reflect the true in vivo situation. [ABSTRACT FROM AUTHOR]

• Explored various isomerization and decomposition pathways for MA, MB and MC radicals, considering not only conventional C–C and C–H β- scission reactions but also including C–O β- scission reactions. • High-level theoretical calculations are conducted to obtain the rate constants for isomerization and decomposition reactions for MA, MB and MC radicals over wide temperature and pressure ranges and the thermodynamics of involved species. • Improved species concentration prediction by updating the calculated rate constants into the kinetic models. Reaction kinetics of radical isomerization and decomposition of three small unsaturated methyl esters of methyl acrylate (MA, C 4 H 6 O 2), methyl butenoate (MB, C 5 H 8 O 2) and methyl crotonate (MC, C 5 H 8 O 2) are systematically studied with high-level quantum chemistry computation. MB and MC are isomers with the C=C double bonds at different positions. The potential energy profiles for these reactions are obtained at the DLPNO-CCSD(T)/CBS(T-Q)//M062X/ma-TZVP level of theory, and the thermodynamics of the involved species are derived at the CCSD(T)/CBS(T-Q) level of theory using the atomization enthalpy method. Our results show that isomerization reactions with stable cyclic transition states have lower reaction barrier heights, making them energetically and kinetically favored. For decomposition reactions, C–C β- scission reactions are more energetically favorable than C–H β- scission reactions, and the C–O β- scission reactions to produce HCHO are the most energetically favorable. The related rate constants are calculated via solving the Rice-Ramsperger-Kassel-Marcus (RRKM)/master equation at 300–2500 K and over a pressure range of 0.01–100 atm along with the high-pressure limit. It is shown that isomerization reaction dominates at low and intermediate temperatures; while as the temperature increases, the importance of decomposition reaction becomes apparent. Pressure is found to have a significant impact on the studied reactions. Additionally, the computed rate constants of this work agree well with the available theoretical results but differ significantly from the estimated results in the literatures. Kinetic reaction mechanisms are further updated, and the results show that through incorporating the presently computed rate constants and thermodynamics, the experimental species concentration distributions can be better reproduced. This work provides the necessary rate constants and thermodynamics for the kinetic model construction of MA, MB, and MC and are expected to help establish more accurate chemical kinetic models of small unsaturated methyl esters, enriching our understanding of the combustion chemistry of biodiesel. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new magnetic polymer adsorbent based on poly(methyl acrylate) was prepared through the ATRP technique. • The participation of PEG diacrylate crosslinker gave the Fe 3 O 4 @SiO 2 -containing adsorbent a high swellability. • The prepared adsorbent performed much better for the removal of Pb (II) ions compared to Hg (II) and Co (II) ions. • After carrying out the adsorption–desorption cycle three times, it was found that the prepared adsorbent has good reusability. • The adsorbent prepared can be a suitable candidate for the adsorption of Pb (II) ions from contaminated water. A new magnetic polymer adsorbent with high swellability was prepared based on a PEG-crosslinked poly(methyl acrylate) via ATRP technique. FT-IR, TGA, CHN, FE-SEM, EDX, XRD, VSM, BET, and DLS measurements were used for the characterization of the prepared adsorbent. After replacing terminal bromines with triethylenetetramine chelating agent, the adsorption process of lead ions led to the removal of these ions from aqueous solutions. The removal of lead ions was investigated using ICP-OES technique. At pH = 7, the equilibrium adsorption capacity increased significantly and reached 37 mg/g at a contact time of 60 min. The adsorption capacity increased with increasing adsorption temperature (up to 40 °C) and initial concentration of lead ions (up to 70 mg/L), while it decreased with increasing adsorbent dose. The Freundlich isotherm better described the process of adsorption of lead ions by the prepared adsorbent. The adsorption kinetic was in greater agreement with pseudo-second-order model. The prepared adsorbent performed much better in adsorbing lead ions compared to cobalt and mercury ions. By performing the adsorption–desorption process three times, it was found that the adsorbent has high reusability. Overall, high swelling behavior and ease of magnetizability are two prominent features of the newly prepared adsorbent. [ABSTRACT FROM AUTHOR]