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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]

• 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]

Radical ring-opening (co)polymerization (RROP) provides an accessible method for synthesizing main chain degradable vinyl polymers. Although the applications of reversible deactivation radical polymerization (RDRP) into RROP have been reported, the use of photo-mediated RDRP methods has received less attention than the thermal process. Here, photo-RROP of the thionolactone dibenzo [c,e]-oxepine-5(7H)-thione (DOT) and methyl acrylate (MA) was studied using photo-iniferter (PI) reversible addition-fragmentation (chain) transfer (RAFT) polymerization at ambient temperature without external radical initiators or photocatalysts. Despite the occurrence of some side reactions including desulfurization-oxygenation and O–S isomerization of DOT promoted by photoexcited thiocarbonyl groups, polymers with thioester linkages in the backbone were prepared, which degraded in the presence of amines and bleach. [Display omitted] • Method for synthesizing main chain degradable vinyl polymers. • Photo-mediated radical ring-opening (co)polymerization. • Copolymerization if thionolactone dibenzo [c,e]-oxepine-5(7H)-thione with methyl acrylate. [ABSTRACT FROM AUTHOR]

Herein we report an organophotocatalyzed one-pot approach for the synthesis of γ-undecalactone from 1-octanol and methyl acrylate using continuous-flow photoreactors. By using readily available and inexpensive 4CzIPN as the photocatalyst, the α-C-H alkylation reaction can be easily scaled up to 3 mol with a catalyst loading of 0.08%. [Display omitted] γ-Undecalactone has a powerful peach aroma and is widely used in the field of flavor and pharmaceutical industry. Herein we report an organophotocatalyzed one-pot approach for the synthesis of γ-undecalactone from 1-octanol and methyl acrylate using continuous-flow photoreactors. By using readily available and inexpensive 4CzIPN as the photocatalyst, the α -C-H alkylation reaction can be easily scaled up to 3 mol with a catalyst loading of 0.08 %. [ABSTRACT FROM AUTHOR]

A panel of toxicology, mode of action (MOA), and cancer risk assessment experts was engaged to derive no-significant-risk-levels (NSRLs) for three lower acrylates: methyl acrylate (MA), ethyl acrylate (EA), and 2-ethylhexyl acrylate (2EHA) using the best available science, data, and methods. The review was structured as a five-round, modified Delphi format, a systematic process for collecting independent and deliberative input from panel members, and it included several procedural elements to reduce potential sources of bias and groupthink. Input from the panel for key decisions in the dose-response assessments resulted in NSRL values of 530 μg/day (330–800 μg/day), 640 μg/day (280–670 μg/day), and 1700 μg/day (1300–2700 μg/day) for MA, EA, and 2EHA, respectively. Novel to this approach were the use of nonneoplastic lesions reported at point of contact where tumors have been reported in laboratory rodents, along with nonlinear extrapolation to low doses (uncertainty factor approach) based upon panel recommendations. Confidence in these values is considered medium to high for exposures applied to the routes of exposure tested (inhalation for MA and EA, dermal for 2EHA), but confidence is considered lower when applied to other routes of exposure. • A panel of dose-response assessment and risk assessment was assembled and engaged using a modified delphi format. • Panelists provided input on No-Significant-Risk-Level (NSRL) derivations for three acrylates. • Based on mode of action the panel recommended that NSRLs be based on tumor precursor effects using an uncertainty factors. • NSRLs of 530, 640, and 1700 μg/day were calculated for methyl, ethyl, and 2-ethylhexyl acrylate, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Afterglow transparent smart wood with photochromism was prepared. • Lignin-modified wood was infiltrated with methyl acrylate and SrAl 2 O 4 :Eu2+,Dy3+. • Luminescent timber changed color from colorless in daylight to green in UV. • Absorption band was detected at 365 nm, and two emission bands at 436 and 517 nm. • Luminous wood provided superior UV protection and superhydrophobic activity. Smart windows that use photochromic colorless wooden materials are an intriguing and urgent area of research. Herein, we create afterglow transparent woods with UV-induced photochromic capability. Infiltrating a lignin-modified wood (LMW) with a solution of methyl acrylate (MA) and rare-earth strontium aluminum oxide (SrAl 2 O 4 : Eu2+, Dy3+; SAOED) yielded afterglow and photochromic translucent wood. Preparing photoluminescent transparent wood effectively requires dispersing SAOED phosphor nanoparticles (NPs) in pre-polymerized MA without clumping. CIE (Commission Internationale de ĺEclairage) Lab colorimetric studies indicated that this transparent timber substrate changed color from colorless in daylight to greenish when exposed to ultraviolet rays. Micrographs taken using a transmission electron microscope (TEM) were analyzed to learn more about the morphology of the synthesized SAOED NPs. Different characterization techniques were applied on the photochromic translucent wood samples, including scanning electron microscopy (SEM), energy-dispersive X-ray analyzer (EDX), hardness properties, wavelength-dispersive X-ray fluorescent spectroscopy (WD-XRF), and absorption and emission spectroscopy. Absorption maximum wavelength was detected at 365 nm. Both 436 nm and 517 nm were observed as emission wavelengths in the developed photoluminescence wood. The results displayed that the manufactured transparent wood introduced superior protection from UV radiation and superhydrophobic activity. UV light triggered a rapid and reversible photochromic reaction in the transparent luminous wood. [ABSTRACT FROM AUTHOR]