Showing papers on "Methyl acrylate published in 2023"
TL;DR: In this article , a cluster-triggered emission (CTE) mechanism was proposed for polyglycidol-acrylates with tunable multicolor emission, where the through-space interaction between the acrylate units formed the clusters.
Abstract: Unconventional fluorescent polymers have attracted increasing attention due to their simple preparation, good biocompatibility, and stable photophysical properties. Polyglycidol-acrylates (PGL-acrylates) with tunable multicolor emission were prepared by one-pot in this study. First, PGL was synthesized by the ring-opening polymerization of glycidol, and then the terminal hydroxyl groups in polyglycidol were modified using propiolic acid ester via the oxa-Michael reaction in situ, forming PGL-acrylates with terminal acrylate units. The fluorescence emission of PGL-acrylate follows the clustering-triggered emission (CTE) mechanism, where the through-space interaction (TSI) between the acrylate units forms the clusters. All of the prepared PGL-acrylates show typical concentration-enhanced emission and excitation-dependent emission, and significant emission at 640 nm was observed. Particularly, PGL-acrylate demonstrated an unusual concentration-excitation-dependent emission (EDE) behavior, in which the maximum excitation and emission wavelengths of the solution showed considerable red-shift with the increased PGL-acrylate concentration. This could come from the increased π–π* interactions with increased double-bond concentration, which stack and drive a more compact structure of the luminescent clusters. The compact cluster structure enhances the TSI effect and expands the delocalized electrons, leading to increased emission and red-shift. As the steric hindrance of the terminal methyl acrylate unit increases, it is difficult to form a more compact cluster structure, and the fluorescence emission is blue-shifted. PGL-acrylate also has low cytotoxicity and good cell imaging ability and is expected to be used in biomedical applications.
1 citations
TL;DR: In this paper , several grades of MAM block copolymer are employed as heterogeneous phase in poly(methyl methacrylate) for producing open-cell (OC) nanostructures without non-foamed solid skins by gas dissolution foaming.
Abstract: The production of open-cell (OC) nanostructures in polymer foams without non-foamed solid skins by gas dissolution foaming has been developed in this work. First, several grades of MAM block copolymer (methyl methacrylate-b-butyl acrylate-b-methyl methacrylate) at high content are employed as heterogeneous phase in poly(methyl methacrylate) for producing OC structures. Atomic force microscopy and extensional rheology are used as methods to understand the main features to obtain OC nanocellular structures. Second, the gas diffusion barrier approach is employed for the first time in polymer blends to avoid the appearance of the solid skins in the borders, which typically appears when the cellular polymer is produced by gas dissolution foaming. The influence of the poly(vinyl alcohol) gas diffusion barrier is analyzed, together with the effect of heterogeneous nucleation provided by MAM copolymer, on the solid skins’ formation. The synergy between both approaches allows obtaining porous nanocellular polymeric films with an OC structure non-constrained by the presence of outer solid skins.
1 citations
TL;DR: In this article , a cesium-exchanged Al-rich Beta zeolite (Cs-Beta) was shown to be highly efficient for the dehydration of methyl lactate (ML) to methyl acrylate (MA).
Abstract: Dehydration of methyl lactate (ML) obtained from biomass is a sustainable route for the production of methyl acrylate (MA). Herein, we demonstrate that cesium-exchanged Al-rich Beta zeolite (Cs-Beta) is highly efficient for the dehydration of ML to MA, exhibiting full ML conversion with 87.4% MA yield at 340 °C. In situ FT-IR spectra and kinetic studies provide evidence that the ML dehydration on the Cs-Beta zeolite follows a forward ion-exchange/dehydration/reverse ion-exchange reaction pathway. Model experiments, DFT calculations, TG-DSC analysis, and FT-IR spectra showed that coke formation competes with the dehydration of ML to MA. Kinetic studies and theoretical simulations demonstrate that cesium cations in the micropores of Beta zeolite have a strong steric hindrance, suppressing the formation of oligomers and coke. These results offer new insights for developing highly selective and stable catalysts for the dehydration of ML to MA in the future.
TL;DR: In this paper , a nickel catalysts were used for the copolymerization of polynorbornene (PNB) and methyl acrylate (MA) with the highest activity achieved being 3.6 × 106 g mol−1 h−1 .
Abstract: 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.
TL;DR: In this article , a simple and efficient method for the synthesis of organofunctional silanes by the thiol-(meth)acrylate addition reaction is presented, where the authors select an optimum initiator/catalyst of the addition reaction for the model reaction involving 3-mercaptopropyltrimethoxysilane and hexyl acrylate.
Abstract: A simple and efficient method for the synthesis of organofunctional silanes by the thiol-(meth)acrylate addition reaction is presented. At first, systematic studies were carried out to select an optimum initiator/catalyst of the addition reaction for the model reaction involving 3-mercaptopropyltrimethoxysilane (MPTMS) and hexyl acrylate. Photoinitiators (in the presence of UV light energy), thermal initiators (such as aza compound and peroxide) as well as catalysts (primary and tertiary amines, phosphines and Lewis acid) were studied. After selecting an effective catalytic system and optimizing the reaction conditions, reactions between the thiol group (i.e. 3-mercaptopropyltrimethoxysilane) and (meth)acrylates containing various functional groups were carried out. All derivatives obtained were characterized by 1H, 13C, 29Si NMR and FT-IR analysis. In reactions carried out at room temperature, in an air atmosphere and in the presence of dimethylphenylphosphine (DMPP) as a catalyst, quantitative conversions of both substrates were obtained within a few minutes. The library of organofunctional silanes was expanded by compounds (containing various functional groups, i.e. alkenyl, epoxy, amino, ether, alkyl, aralkyl, fluoroalkyl) which were obtained in the thiol-Michael addition of 3-mercaptopropyltrimethoxysilane to a group of organofunctional (meth)acrylic acid esters.
TL;DR: In this paper , a series of polyacrylonitrile (PAN) co- or terpolymers as PAN-based carbon fiber precursors was prepared using methyl acrylate (MA) as neutral comonomer and fumaric acid (fa) or maleic acid(ma) as acidic comonomers which is trans/cis isomer.
Abstract: A series of Polyacrylonitrile (PAN) co- or terpolymers as PAN-based carbon fiber precursors was prepared using methyl acrylate (MA) as neutral comonomer and fumaric acid (fa) or maleic acid (ma) as acidic comonomer which is trans/cis isomer, respectively. In order to establish the optimized condition of polymerization, PAN polymers with different acrylonitrile weight ratios (92, 94, and 96 wt%) were synthesized with appropriate yield via stepwise solution polymerization system. The efficiency of cyclization reaction of PAN polymers containing fa or ma were dramatically improved as compared to PAN homopolymer, and initiation of cyclization showed a rapid progress at 210 °C despite short thermal treatment time during thermal oxidative stabilization (TOS). Additionally, the char yield of PAN co- or terpolymers was reasonable value which was similar to PAN homopolymer.
TL;DR: In this paper , isopropyl alcohol (IPA) selective membranes were prepared from poly(methyl methacrylate-co-butyl acrylate) copolymers based on their relative solubility parameter values.
TL;DR: In this article , a Na-FAU zeolite catalyst impregnated with multifunctional diamines was experimentally evaluated for dehydration of methyl lactate to acrylic acid and methyl acrylate.
Abstract: Dehydration of methyl lactate to acrylic acid and methyl acrylate was experimentally evaluated over a Na-FAU zeolite catalyst impregnated with multifunctional diamines. 1,2-Bis(4-pyridyl)ethane (12BPE) and 4,4′-trimethylenedipyridine (44TMDP), at a nominal loading of 40 wt % or two molecules per Na-FAU supercage, afforded a dehydration selectivity of 96 ± 3% over 2000 min time on stream. Although 12BPE and 44TMDP have van der Waals diameters approximately 90% of the Na-FAU window opening diameter, both flexible diamines interact with internal active sites of Na-FAU as characterized by infrared spectroscopy. During continuous reaction at 300 °C, the amine loadings in Na-FAU remained constant for 12BPE but decreased as much as 83% for 44TMDP. Tuning the weighted hourly space velocity (WHSV) from 0.9 to 0.2 h–1 afforded a yield as high as 92% at a selectivity of 96% with 44TMDP impregnated Na-FAU, resulting in the highest yield reported to date.
28 Jan 2023
TL;DR: In this paper , the viscosity of poly methyl methacrylate (PMMA)/poly ethylene glycol (PEG) blends in tetra hydro furan (THF) as a common solvent, were carried out for different blend compositions at 30, 40 and 50°C.
Abstract: Measurements of viscosity of poly methyl methacrylate (PMMA)/poly ethylene glycol (PEG) blends in tetra hydro furan (THF) as a common solvent, were carried out for different blend compositions at 30, 40 and 50°C. Using the viscosity data, interaction parameters µ were computed to determine miscibility. These values revealed that the blend was miscible when the PMMA content was more than 30% of the blend. Further, the results revealed that the change in temperature has significant effect on the miscibility of PMMA/PEG polymer blends. The simple of (PMMA/PEG) blends were characterized by using (FTIR).
TL;DR: In this paper , a pretreatment was proposed to improve the efficiency of the TMAH-methanol solution in a micro tube. But, the results were only applied to a UV-cured acrylate copolymer.
TL;DR: In this paper , a previous mechanistic model developed for methyl acrylate/t-BuAAm copolymerization is extended to represent the terpolymerization system with non-functional monomers.
Abstract: Multi-functional polymers used for personal care products can be synthesized by radical polymerization of acrylic acid (AA) in alcohol/water solutions with non-functional monomers such as methyl acrylate (MA) and N-tert-butylacrylamide (t-BuAAm). However, solvents capable of forming or disrupting hydrogen bonds cause the polymerization kinetics of these monomers to deviate from their polymerization behaviour in bulk and non-polar solvents. In this work, a previous mechanistic model developed for MA/t-BuAAm copolymerization is extended to represent the terpolymerization system MA/t-BuAAm/AA. The additional kinetic coefficients required for the system are estimated from fitting to AA homopolymerizations and AA/MA and AA/t-BuAAm copolymerizations conducted in an ethanol/water solution. In-situ nuclear magnetic resonance (NMR) spectroscopy is used to follow monomer conversions and composition drift behaviour, with the molar mass distributions of the polymer products characterized by size-exclusion chromatography. Although AA is more reactive than MA in non-polar solvents, the reactivities of the two monomers equalize under the experimental conditions examined. Thus, the batch and semi-batch terpolymerization data collected are represented equally well by a reduced acrylate/t-BuAAm copolymerization model and the full terpolymerization implementation.
TL;DR: In this paper , the authors present the correlation of thermal, morphological and melt rheological properties of poly(ethylene oxide)/poly(methyl acrylate) (PEO/PMA) blends and PEO/poly(n-butyl methacrylate), and show that these properties are correlated.
Abstract: This study presents the correlation of thermal, morphological and melt rheological properties of poly(ethylene oxide)/poly(methyl acrylate) (PEO/PMA) blends and PEO/poly(n-butyl methacrylate) (PEO/PnBMA) blends. The miscibility and correlation of these properties were assessed through thermal analysis such as glass transition temperature (Tg) and apparent melting temperature (Tm), morphological study and melt rheological analysis of the blends. The results show that PEO/PMA blends are miscible as suggested by the number of Tg values that follow the Fox equation and the development of homogeneous mixtures in the molten state (T = 80 °C). On the other hand, PEO/PnBMA blends are immiscible as shown by the constancy of the Tg values of PEO throughout the blend compositions. The immiscibility was confirmed by optical microscopy which shows the matrix-droplet and co-continuous morphologies (i.e. heterogeneous mixtures) in the PEO/PnBMA blends at T = 80 °C. Melt rheological properties of the immiscible PEO/PnBMA blends are affected by the blend compositions and show significant deviation from Maxwell behaviour. Conversely, the rheological properties of the miscible PEO/PMA blends show close to Maxwell behaviour. Hence, the correlation of thermal, morphological and melt rheological studies is discussed for both miscible and immiscible PEO/polyacrylate blends. © 2023 Society of Industrial Chemistry.
TL;DR: In this article , the catalytic behavior of "ligandless" palladium(II) acetate in the Heck arylation reaction of iodobenzene with methyl acrylate is examined at (ultra-)low catalyst loadings using in situ spectroscopy.
TL;DR: A graft copolymer is synthesized by grafting a mixture of 2-(dimethylamino) ethyl acrylate (DMAEA) and 2-acrylamido-2-methyl propane sulfonic acid (AMPS) monomers onto the dextrin, polysaccharide backbone via free radical polymerization process using potassium peroxydisulfate (KPS) as radical initiator in aqueous phase as discussed by the authors .
Abstract: A graft copolymer is synthesized by grafting a mixture of 2-(dimethylamino) ethyl acrylate (DMAEA) and 2-acrylamido-2-methyl propane sulfonic acid (AMPS) monomers onto the dextrin, polysaccharide backbone via free radical polymerization process using potassium peroxydisulfate (KPS) as radical initiator in aqueous phase. Various characterization techniques like 1H and 13C NMR, FT-IR, SEM, EDAX, and XRD analysis are used to characterize the copolymer. The polymer is used as an adsorbent for the removal of nitrophenols namely ortho-nitrophenol (ONP), para-nitrophenol (PNP), and 2,4- dinitrophenol (DNP) from their water solutions. Adsorption dynamics, kinetics, isotherms, and thermodynamics are studied. The maximum nitrophenol adsorption occurs at time 80 min, temperature 45°C, pH 3.5 (DNP), and 4.5 (ONP and PNP), polymer dose 30 mg/L. The nitrophenol adsorption data are well-fitted with the Langmuir isotherm model with maximum adsorption capacity ( q m ) 215.26 mg g−1 for ONP, 223.60 mg g−1 for PNP, and 288.24 mg g−1 for DNP. The equilibrium kinetics follow pseudo-second-order kinetic model. Thermodynamic values unfold that the following nitrophenol adsorption onto the polymer surface is spontaneous and endothermic in nature. The value of Gibb's free energy for the nitrophenol adsorption is in the range of −6.5 to −9.5 kJ mol−1. The preferential nitrophenol adsorption by the copolymer is followed in the order ONP
TL;DR: In this paper , the synthesis and characterization of cobalt(II) (3, 4) and acetato cobalt (III) (5) complexes with two tripodal tetradentate diamino-bis(phenolate) ligands (L1 and L2) are reported.
TL;DR: In this paper , the copper methoxide compound IPrCuOMe was unexpectedly formed in a reaction of IPrcuPPh2 with methyl acrylate and the alkoxide product was identified from the reaction mixture spectroscopically and structurally characterized.
Abstract: 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.
TL;DR: In this paper , three unsymmetrical arylamine based pyridine-imine ligands and the corresponding nickel and palladium complexes were prepared and used for ethylene oligomerization.
01 Jan 2023
TL;DR: In this paper , the conformational, crystalline and rheological properties of poly(octadecyl-stat-methyl acrylate) (P(ODAx-stat)-MAy)Nb) random copolymers are reported.
TL;DR: In this article , bifunctional quaternary ammonium salt phase-transfer organocatalysts were synthesized in four steps from (+)-camphor-derived 1,3-diamines.
Abstract: Ten novel bifunctional quaternary ammonium salt phase-transfer organocatalysts were synthesized in four steps from (+)-camphor-derived 1,3-diamines. These quaternary ammonium salts contained either (thio)urea or squaramide hydrogen bond donor groups in combination with either trifluoroacetate or iodide as the counteranion. Their organocatalytic activity was evaluated in electrophilic heterofunctionalizations of β-keto esters and in the Michael addition of a glycine Schiff base with methyl acrylate. α-Fluorination and chlorination of β-keto esters proceeded with full conversion and low enantioselectivities (up to 29% ee). Similarly, the Michael addition of a glycine Schiff base with methyl acrylate proceeded with full conversion and up to 11% ee. The new catalysts have been fully characterized; the stereochemistry at the C-2 chiral center was unambiguously determined.
TL;DR: In this paper , 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 was used in 1,3-dipolar cycloaddition reactions for the synthesis of chiral pyrrolidines.
TL;DR: A series of new Morita-Baylis-Hillman acetates were prepared and reacted with methanesulfonamide (K2CO3, DMF, 23 °C) to produce tertiary dihydroquinoline sulfonamides in high yields as mentioned in this paper .
Abstract: A series of new Morita–Baylis–Hillman acetates were prepared and reacted with methanesulfonamide (K2CO3, DMF, 23 °C) to produce tertiary dihydroquinoline sulfonamides in high yields. Subsequent efforts to eliminate the methylsulfonyl group from these derivatives (K2CO3, DMF, 90 °C) as a route to quinolines were met with mixed results. Although dihydroquinoline sulfonamides prepared from ethyl acrylate and acrylonitrile generally underwent elimination to give excellent yields of quinolines, those generated from 3-buten-2-one failed to undergo elimination and instead decomposed. The failure of these ketone substrates to aromatize presumably derives from the enolizable methyl ketone at C-3. Finally, the attempted aromatization of the acrylate-derived 6,7-difluoro-1,2-dihydroquinoline sulfonamide demonstrated that other interesting processes could occur in preference to the desired elimination.
TL;DR: In this article , a series of siloxane-functionalized Vanadium Phosphorus Oxide (VPO)-TiO2 catalysts were used to catalyze the co-activation reaction of aldehyde condensation with esterification.
Abstract: A series of siloxane-functionalized Vanadium Phosphorus Oxide (VPO)-TiO2 catalysts were prepared by wet-solid mechanochemical method and used to catalyze the co-activation reaction of aldehyde condensation with esterification, a novel route...
TL;DR: In this paper , a solvent-based method to recover acrylate polymer from display film waste was applied to calculate the solubility of poly( tert-butyl acryl) in 18 different organic solvents, including 2-butanol and methyl acetate.
Abstract: Acrylate polymer is widely used to manufacture display films as an adhesive. Improper disposal of acrylate polymer-containing display film waste (a kind of E-waste) may cause serious environmental problems. As an effort to develop a display film waste treatment strategy, this study applied a solvent-based method to recover acrylate polymer from display film waste. The solubility of acrylate polymer (e.g. poly( tert-butyl acrylate)) in 18 different organic solvents was calculated using Hansen solubility parameters. As a result, 2-butanol and methyl acetate were chosen as organic solvents for the acrylate polymer recovery from the display film waste. Effects of various recovery parameters (e.g. temperature, time, and stirring speed) on the recovery of acrylate polymer in five different solvent systems consisting of 2-butanol and methyl acetate (2-butanol, methyl acetate, 1:1 mixture, 1:2 mixture, and 2:1 mixture) were explored. 2-Butanol was found to be a better solvent than any others because it is more hydrophobic than methyl acetate. The recovery condition at which the highest acrylate polymer recovery yield in 2-butanol was obtained was T = 30 °C, t = 1 h, and stirring speed of 250 r/min, reaching 8.28 wt%. This study would help to develop an E-waste recycling method that can be recovering value-added products from E-waste.
06 Jun 2023
TL;DR: In this article , a rate law was established through the method of initial rates, comparing the rates of reactions with different initial concentrations to one another, and additional reactions were run with active cooling to observe the effects on rate and reaction progress.
Abstract: The objective of this research was to determine kinetic and thermodynamic data about the reaction between ethylene diamine and methyl acrylate which is used in the production of PAMAM dendrimers. Establishing a rate law and finding values such as rate constant, activation energy, and Arrhenius coefficient will help in determining the best possible conditions for the reaction. A rate law was established through the method of initial rates, comparing the rates of reactions with different initial concentrations to one another. Additional reactions were run with active cooling to observe the effects on rate and reaction progress, and finally reactions were run with varied reactant feed rates in order to test temperature controllability for future optimization work.