Showing papers on "Methacrylic acid published in 2020"
TL;DR: In this article, N doped carbon dots (N-CDs) were prepared by hydrothermal method in methacrylic acid and n-butylamine precursors.
87 citations
TL;DR: Novel dummy magnetic molecularly imprinted polymers (dex-MMIPs) were prepared for highly selective recognition and fast enrichment of acrylamide (AA) in potato chips.
48 citations
TL;DR: This work aimed to investigate the interactions between the CAP as a template and functional monomers required for synthesizing efficient molecularly imprinted polymers for recognition and isolation of CAP based on density functional theory.
Abstract: Molecular imprinting technology is a promising method for detecting chloramphenicol (CAP), a broad-spectrum antibiotic with potential toxicity to humans, in animal-derived foods. This work aimed to investigate the interactions between the CAP as a template and functional monomers required for synthesizing efficient molecularly imprinted polymers for recognition and isolation of CAP based on density functional theory. The most suitable monomer, methacrylic acid (MAA), was determined based on interaction energies and Gibbs free energy changes. Further, the reaction sites of CAP and MAA was predicted through the frontier molecular orbitals and molecular electrostatic potentials. Atoms in molecules topology analysis and non-covalent interactions reduced density gradient were applied to investigate different types of non-covalent and inter-atomic interactions. The simulation results showed that CAP was the main electron donor, while MAA was the main electron acceptor. Moreover, the CAP–MAA complex simultaneously involved N-H···O and C=O···H double hydrogen bonds, where the strength of the latter was greater than that of the former. The existence of hydrogen bonds was also confirmed by theoretical and experimental hydrogen nuclear magnetic resonance and Fourier transform infrared spectroscopic analyses. This research can act as an important reference for intermolecular interactions and provide strong theoretical guidance regarding CAP in the synthesis of molecularly imprinted polymers.
37 citations
TL;DR: In this paper, microcrystalline cellulose (MCC) extracted from bamboo powder was used as bio-based carbon source in intumescent system to improve both the dispersibility and compatibility of in/with polylactic acid (PLA).
Abstract: Microcrystalline cellulose (MCC) extracted from bamboo powder was used as bio-based carbon source in intumescent system. Before using, MCC was modified with methacrylic acid (MA) by grafting polymerization to prepare MA-MCC, which may improve both the dispersibility and compatibility of in/with polylactic acid (PLA). MA-MCC, together with ammonium polyphosphate, was blended into PLA by melt compounding. The flame retardant properties of the composites were characterized by the limiting oxygen index (LOI), UL-94 vertical burning test and cone calorimeter test. The results showed that the LOI of PLA composite sample containing 3% MA-MCC and 7% APP could reach up to 26.8% and pass V-0 rating in UL-94 test. The addition of APP and MA-MCC could also decrease the peak heat release rate from 556 kW/m2 of neat PLA to 456 kW/m2 and form a continuous, dense, homogeneous residue char to prevent PLA from further burning. Thermogravimetric analysis showed that the presence of APP and MA-MCC could enhance the thermal stability of the composites, which is also essential for the improvement of fire performance. The mechanical properties of PLA composites were also improved with the unnotched impact strength increased to 8.16 kJ/m2 and Young’s modulus increased to 1612.8 MPa. The possible mechanisms for the improvement of flame retardancy and mechanical properties had also been proposed.
35 citations
05 Feb 2020
TL;DR: Economic feasibility, better sorption capacity, and efficient regeneration and reusability even after four consecutive sorption–desorption cycles ascertained PMA/nMMT as a potential sorbent for AMX and DF uptake from the aqueous phase.
Abstract: Herein, a simplistic redox polymerization strategy was utilized for the fabrication of a poly(methacrylic acid)/montmorillonite hydrogel nanocomposite (PMA/nMMT) and probed as a sorbent for sequestration of two pharmaceutical contaminants, viz., amoxicillin (AMX) and diclofenac (DF), from wastewater. The synthesized hydrogel nanocomposite was characterized by the Fourier transform infrared, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy–energy dispersive X-ray spectroscopy, and transmission electron microscopy techniques to analyze structural characteristics and sorption interactions. The efficacy of PMA/nMMT was thoroughly investigated for the sequestration of AMX and DF from the aquatic phase with a variation in operative variables like agitation time, sorbent dosage, pH, and initial sorbate concentration. The reaction kinetics was essentially consistent with the pseudo-second-order model with rate dominated by the intraparticle diffusion model as well as the film diff...
31 citations
TL;DR: A deep eutectic solvent was prepared from choline chloride and methacrylic acid and used as an eco-friendly surfactant and functional monomer and DES-LINs had better adsorption capacity for levofloxacin than common LINs.
Abstract: A deep eutectic solvent (DES) was prepared from choline chloride (ChCl) and methacrylic acid (MAA) and used as an eco-friendly surfactant and functional monomer. The process of producing DES and its free energy of formation (ΔG = -37.225 kcal mol-1) were evaluated theoretically by density-functional theory. The designed DES (ChCl-MAA) was introduced as a novel eco-friendly functional monomer (MAA as the control group) during the preparation of levofloxacin-imprinted nanoparticles (LINs) based on molecular imprinting technology. The nanoparticles were characterized using a range of techniques. The nanoparticles were applied as an adsorbing material to the selective removal of levofloxacin from environmental waste water. The selective removal and adsorption capacity of the adsorbing material were evaluated by high-performance liquid chromatography. Based on the introduction of DES, DES-LINs had better adsorption capacity for levofloxacin than common LINs. This method had the simple operation, rapid adsorption and efficient decontamination.
25 citations
TL;DR: In this article, a series of methacrylic photopolymerizable composites with potential dental applications were prepared and examined, and the ability to release remineralizing calcium ions was also checked.
23 citations
TL;DR: In this article, a series of novel poly(methacrylic acid)/laponite RDS (PMAA/Lap RDS) nanocomposite hydrogels crosslinked by N,N’-methylene bisacrylamide were synthesized via free radical polymerization by using potassium persulfate as initiator.
Abstract: In this paper, a series of novel poly(methacrylic acid)/laponite RDS (PMAA/Lap RDS) nanocomposite hydrogels crosslinked by N,N’-methylene bisacrylamide were synthesized via free radical polymerization by using potassium persulfate as initiator. The main novelty of this paper refers to the detail investigation of how the laponite RDS influenced of the pKa, and consequently, the water-uptake of these nanocomposites. In parallel, the evidence of incorporation and interactions of the materials was confirmed by scanning electron microscopy and Fourier transform infrared spectra techniques. By the X-ray diffraction technique (XRD), it was possible to confirm the exfoliation/intercalation configuration of the nanoclay laponite RDS (Lap RDS) into the PMAA matrix. Hydrophilic properties, measured by swelling degree (SD), indicated that the presence of Lap RDS influenced the water uptake capability of the nanocomposite, reaching a maximum of 91 ± 2 g/g for nanocomposites constituted by 5 % of nanoclay. Besides, the pKa of the nanocomposite can be adjusted by nanoclay content. In this way, the ability of these hydrogels to respond to pH values can be useful to act as trigger in controlled release systems.
22 citations
TL;DR: In this article, the authors synthesize polymerization-induced self-assembly (PISA) in dilute aqueous solution using a reversible addition-fragmentation chain transfer (RAFT) approach.
21 citations
TL;DR: In this article, a series of multi-crosslinkable, self-healing coatings were developed to enhance the mechanical properties through tandem UV-curing and Diels-Alder (DA) chemistry.
21 citations
TL;DR: In this paper, the synthesis and optimization of a green PVA-co-poly (MAA) adsorbent by free radical polymerization using N,N′-methylene-bis-acrylamide and potassium persulphate as a cross-linker-initiator system was focused.
Abstract: The present paper is focused on the synthesis and optimization of a green PVA-co-poly(MAA) adsorbent by free radical polymerization using N,N′-methylene-bis-acrylamide and potassium persulphate as a cross-linker–initiator system. The surface morphology and structural properties were studied by the techniques such as FTIR, FESEM and XRD. The synthesized adsorbent was found to possess the maximum adsorption capacity of 0.761 mg g−1 at the equilibrium of methylene blue dye from an aqueous solution at 10 ppm concentration, 500 mg of sample dose, at a pH of 7 and at a temperature of 30 °C. The kinetic study confirmed that the dye adsorption followed the pseudo-second-order model and was found to fit well with the Langmuir isotherm model. The adsorbent of PVA and methacrylic acid (MAA) also exhibits brilliant regeneration efficiency for the four successive adsorption–desorption cycles. The synthesized semi-IPN hydrogel was found to be a cost-effective and renewable propitious candidate with excellent regeneration efficiency to be used as a green adsorbent for the removal of methylene blue from the wastewater effluents.
TL;DR: In this paper, the authors reported the synthesis, characterization and evaluation of p53-poly(MAA-co-EGDMA)@GO-Fe3O4 as SPE materials for selective extraction of wild p53 protein.
Abstract: The p53 protein plays an important role by acting as a transcription factor to regulate gene expression and its genetic mutation has been reported as the most common genetic alterations in human cancer diseases. This opens possibilities for the development of early identification of cancer by utilizing p53 protein as tumor biomarkers. In this work we report the synthesis, characterization and evaluation of p53-poly(MAA-co-EGDMA)@GO-Fe3O4 as SPE materials for selective extraction of wild p53 protein. The magnetic material p53-poly(MAA-co-EGDMA)@GO-Fe3O4 (MIP@GO-Fe3O4) is successfully prepared with GO-Fe3O4 from kusambi wood (Schleichera oleosa) as the host material, p53 as a template molecule, methacrylic acid (MAA) as a monomer, ethylene glycol dimethacrylate (EGDMA) as a crosslinker, benzoyl peroxide (BPO) as an initiator and acetone/ethanol as a porogen. Synthesis is carried out using a bulk polymerization method. To find out the best ratio that produces the highest MIP@GO-Fe3O4 mass, the five variations of the volume ratio of template, monomer and crosslinker (P1–P5) are investigated. It was found that the volume ratio of template, monomer and crosslinker that produced the highest MIP@GO-Fe3O4 mass is obtained at P3 volume ratio (1:4:8 mL, which is further polymerized with GO-Fe3O4 as much as 0.6239 g). Swelling ratio studies using 3 (three) solvents namely chloroform, acetone and methanol show that the swelling ratio values obtained are 1.46, 1.24 and 1.23 g/g, respectively. These results indicate that methanol is the best solvent for use in the rebinding process of MIP@GO-Fe3O4 material. Based on the analysis by FTIR, XRD, SEM-EDX and BET-BJH, the resulting MIP@GO-Fe3O4 material is expected to be used later for wild p53 preconcentration from various biological samples.
TL;DR: In this paper, mixed matrix membranes were prepared from oppositely charged inorganic (INPs) and polymeric (PNPs) nanoparticles using spin coating method using spin-coating method.
TL;DR: These alkene-containing structures are shown to effectively encapsulate small alkyl thiols as guests within the central cavity in aqueous solution, preventing evaporation at elevated temperatures (ΔT ≈ 25 K).
Abstract: Eight alkene-functionalized molybdenum-based spherical Keplerate-type (inorganic fullerene) structures have been obtained via both direct and multistep synthetic approaches. Driven by the opportunity to design unique host–guest interactions within hydrophobic, π-electron rich confined environments, we have synthesised {(NH4)42[Mo132O372(L)30(H2O)72]}, where L = (1) acrylic acid, (2) crotonic acid, (3) methacrylic acid, (4) tiglic acid, (5) 3-butenoic acid, (6) 4-pentenoic acid, (7) 5-hexenoic acid, and (8) sorbic acid. The compounds, which are obtained in good yield (10–40%), contain 30 carboxylate-coordinated alkene ligands which create a central cavity with hydrophobic character. Extensive Nuclear Magnetic Resonance (NMR) spectroscopy studies contribute significantly to the complete characterisation of the structures obtained, including both 1D and 2D measurements. In addition, single-crystal X-ray crystallography and subsequently-generated electron density maps are employed to highlight the distribution in ligand tail positions. These alkene-containing structures are shown to effectively encapsulate small alkyl thiols (1-propanethiol (A), 2-propanethiol (B), 1-butanethiol (C), 2-butanethiol (D) and 2-methyl-1-propanethiol (E)) as guests within the central cavity in aqueous solution. The hydrophobically driven clustering of up to 6 equivalents of volatile thiol guests within the central cavity of the Keplerate-type structure results in effective thermal protection, preventing evaporation at elevated temperatures (ΔT ≈ 25 K).
TL;DR: In this article, a composite was obtained by including methacrylic acid as a co-monomer in the microgel, in order to position carboxylic acid moieties within the polymeric matrix, which via preconcentration of metal organic framework precursors would trigger confined heterogeneous nucleation.
Abstract: Composite materials featuring a synergic combination of interesting properties such as stimuli responsiveness and tailored porosity are highly appealing due to their multiple possible applications. We hereby present an example which brings together such features by using poly(N-isopropyl-acrylamide)-derived thermo-responsive microgels and Zn-based Metal Organic Framework (MOF) ZIF-8, capable of selective adsorption. Such a composite was obtained by including methacrylic acid as a co-monomer in the microgel, in order to position carboxylic acid moieties within the polymeric matrix, which via preconcentration of MOF precursors would trigger confined heterogeneous nucleation. The highly integrated composite obtained features thermoresponsivity and permanent porosity. Methylene blue adsorption/desorption experiments were performed, revealing a dramatic enhancement of its cargo capacity together with an increased release efficiency.
TL;DR: In this paper, flexible track-etched membrane modification by photograft polymerization of methacrylic acid and subsequent formation of interpolyelectrolyte complexes with poly(allylamine) for enhancement of properties of electrochemical sensor was discussed.
Abstract: This article concerns studies of flexible track-etched membrane modification by photograft polymerization of methacrylic acid and subsequent formation of interpolyelectrolyte complexes with poly(allylamine) for enhancement of properties of electrochemical sensor. Optimal conditions leading to functionalization of the surface and maintenance of the pore structure were found. Membranes were characterized by SEM, FTIR, XPS, gas permeability and colorimetric assay. Square wave anodic stripping voltammetry (SW-ASV) was used for detection of Pb2+. Limits of detection (LOD) for sensors based on non-modified PET TeMs, membranes modified by graft polymerization of methacrylic acid (PET TeMs-g-PMAA) and membranes modified with interpolyelectrolyte complexes with poly(allylamine) (PET TeMs-g-PMAA-PAlAm) are 3.03, 2.78 and 1.25 µg/L, respectively. Thus, it was shown that the formation of interpolyelectrolyte complexes on the membranes leads to a more accurate detection of lead ions.
TL;DR: In this paper, a biodegradable poly(lactic acid-methacrylic acid) P(LA-MAA) crosslinked polymer hydrogel was formulated in-situ via one-pot reaction employing polycondensation of lactic acid and methacric acid followed by free radical polymerization with N,N-methylene diacrylamide crosslinker.
TL;DR: An extensive library of CAC/CMC values has been compiled for PAA- and PMAA-based macroRAFT agents at different pH conditions, providing important information related to the mechanistic understanding and optimization of macroRAFT-assisted emulsion polymerization.
TL;DR: A novel type of interpenetrating polymer network (IPN) hydrogel beads composed of locust bean gum (LBG)-graft-methacrylic acid (MAA) and sodium alginate (SA) with different compositions were prepar...
Abstract: A novel type of interpenetrating polymer network (IPN) hydrogel beads composed of locust bean gum (LBG)-graft-methacrylic acid (MAA) and sodium alginate (SA) with different compositions were prepar...
TL;DR: In this article, statistical copolymers of methacrylic acid and methyl methacrylate were synthesized via free radical catalytic chain transfer polymerization (CCTP) in emulsion to form a hydrophilic emulsifier/surfactant.
TL;DR: Investigation of a shell polymer coated with a gastro-resistant shell polymer that does not dissolve at lower pH present in the stomach, but only later at a higher pH in the small intestine revealed that both the monomer ratio of methacrylic acid to methyl methacrylate in the copolymer and the utilized solvent are determining factors in the release performance of the final particles.
TL;DR: In this paper, three kinds of random polymers were designed and synthesized via polymerization reaction of styrene (St), methacrylic acid (MAA), 2-hydroxypropyl acrylate (HPA), and vinyl sulfonate sodium (VS), respectively.
TL;DR: In this article, an ion-imprinting technology was used to prepare the lanthanum ionimprinted polymer, La-IIP-MAA/Fe3O4-GO with magnetic graphene oxide as a carrier and methacrylic acid as a functional monomer.
29 Jan 2020
TL;DR: In this article, hydrogels nanoparticles of carbopol were prepared by free-radical polymerization technique and Methacrylic acid (MAA) imparted the pH-sensitive response to formulations.
Abstract: Hydrogels nanoparticles of carbopol were prepared by free-radical polymerization technique. Methacrylic acid (MAA) imparted the pH-sensitive response to formulations. pH-sensitive behavior of the p...
TL;DR: Seeded emulsion polymerizations of 2-(dimethylamino)ethyl methacrylate (DMAEMA) and methacrylic acid (MAA) were performed in presence of poly(2-hydroxyehtyl methacRYlate) (PHEMA) particles as seed to fabricate Janus particles as discussed by the authors.
TL;DR: In this paper, gelatin and methacrylic acid are combined to construct a hydrogen-bonded hydrogel with high Young's modulus and fracture energy of 11 MPa and 8.5 kJ m-2.
Abstract: Mechanically robust protein-based hydrogels are strongly desired but their construction remains a significant challenge. In this work, gelatin, together with methacrylic acid, is used to construct a novel hydrogen-bonded hydrogel through a facile low-temperature polymerization and a subsequent dry-swell process. The obtained gel is extremely stiff and tough with a high Young's modulus and a fracture energy of 11 MPa and 8.5 kJ m-2, respectively, which are comparable to the performance of tough synthetic hydrogels, rubber, cartilage, and skin. These gels also show recovery and healing properties as well as biocompatibility and stability in physiological saline solutions. The gel is easy to prepare and exhibits a wide range of functional properties, making it a promising load-bearing material for medical applications.
TL;DR: In this article, the effects of various physico-chemical parameters such as pH, polymer concentration, salinity, buffer concentration and incubation time on the solubilization and precipitation of two pH-sensitive Eudragit polymers were investigated via systematic studies.
Abstract: Poly (methyl methacrylate) derivatives such as Eudragit are polymers largely used for drug encapsulation and in controlled oral drug delivery. With special focusing on those applications , solubilization and precipitation conditions of two pH-sensitive Eudragit polymers namely L100 and E100 were investigated via systematic studies. Effects of various physico-chemical parameters such as pH, polymer concentration, salinity, buffer concentration and incubation time on the solubilization and precipitation of these polymers were studied. In addition, pH titration of both polymers was reported. Considering both macroscopic and quantitative aspects such as the final mean particle size, size distribution, morphology and the zeta potential, it was established that the different pre-cited parameters could not be dissociated and exert a synergic action on the solubilization and precipitation of both polymers. In this study, the solubilization and the precipitation domains were for the first time clearly established by considering the above-mentioned parameters. Moreover, it was found that Eudragit L100 and E100 did not behave as classic polyelectrolytes since solubilization and precipitation domains were not affected by ionic strength. Titration curves revealed two equivalences that helped estimating carboxylic content of Eudragit L100 (6 mmol/g) and
TL;DR: In this paper, the effects of various types of polyelectrolytes and functionalized particles on the properties of soft electrodes in the CapMix process were investigated, and a charge-doped pair of electrodes exhibited power production that was almost 1 and 10 times higher than the power production in systems with ion exchange membranes or neat AC electrodes, respectively.
TL;DR: Results indicated that the pH-sensitive semi-interpenetrating polymer network hydrogels based on sodium carboxymethyl cellulose and poly(methacrylic acid) were a promising vehicle for oral insulin delivery systems.
Abstract: In this research, pH-sensitive semi-interpenetrating polymer network hydrogels based on sodium carboxymethyl cellulose and poly(methacrylic acid) were synthesized using free radical polymerization ...
TL;DR: In this paper, the microwave assisted synthesis of superabsorbent gum gellan cross-linked poly(acrylic-co- methacrylic acid) hydrogel [GG-cl-poly(AA-Co-MAA] was presented by the simultaneous graft copolymerization using ammonium persulfate as the initiator and N,N′-methylene-bis-acrylamide as the crosslinker for the removal of cationic dyes [malachite green (MG) and methylene blue (MB)].
Abstract: The present work highlights the microwave-assisted synthesis of novel superabsorbent gum gellan cross-linked poly(acrylic-co- methacrylic acid) hydrogel [GG-cl-poly(AA-co-MAA)] prepared by the simultaneous graft copolymerization using ammonium persulfate as the initiator and N,N′-methylene-bis-acrylamide as the cross-linker for the removal of cationic dyes [malachite green (MG) and methylene blue (MB)]. The GG and hydrogel were studied by using Fourier-transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction spectroscopic techniques. Swelling studies were conducted out in various concentrations of initiator, monomer, and cross-linker. The outstanding dye removal efficiency of ~ 99% for MG and ~ 95% for MB was found at the initial dye concentration of 50 mg L−1 with an adsorbent dose of 500 mg within the time duration of 6 h and 25 °C. The adsorption kinetics data for both MG and MB dyes exhibited the pseudo-first-order kinetics.