Divinylbenzene Copolymer Research Articles

Application of Functionalized DVB-co-GMA Polymeric Microspheres in the Enhanced Sorption Process of Hazardous Dyes from Dyeing Baths.

Intensive development of many industries, including textile, paper, plastic or food, generate huge amounts of wastewaters containing not only toxic dyes but also harmful auxiliaries such as salts, acid, bases, surfactants, oxidants, heavy metal ions. The search for effective pollutant adsorbents is a huge challenge for scientists. Synthesis of divinylbenzene copolymer with glycidyl methacrylate functionalized with triethylenetetramine (DVB-co-GMA-TETA) resin was performed and the obtained microspheres were evaluated as a potential adsorbent for acid dye removal from dyeing effluents. The sorption capacities were equal to 142.4 mg/g for C.I. Acid Green 16 (AG16), 172 mg/g for C.I. Acid Violet 1 (AV1) and 216.3 mg/g for C.I. Acid Red 18 (AR18). Non-linear fitting of the Freundlich isotherm to experimental data was confirmed rather than the Langmuir, Temkin and Dubinin-Radushkevich. The kinetic studies revealed that intraparticle diffusion is the rate-limiting step during dye adsorption. Auxiliaries such as Na2SO4 (5–25 g/L), CH3COOH (0.25–1.5 g/L) and anionic surfactant (0.1–0.5 g/L) present in the dyeing baths enhance the dye adsorption by the resin in most cases. Regeneration of DVB-co-GMA-TETA is possible using 1 M NaCl-50% v/v CH3OH.

A Visible-Light-Powered Polymerization Method for the Immobilization of Enantioselective Organocatalysts into Microreactors.

A versatile one‐step photopolymerization approach for the immobilization of enantioselective organocatalysts is presented. Chiral organocatalyst‐containing monoliths based on polystyrene divinylbenzene copolymer were generated inside channels of microfluidic chips. Exemplary performance tests were performed for the monolithic Hayashi–Jørgensen catalyst in continuous flow, which showed good results for the Michael addition of aldehydes to nitroalkenes in terms of stereoselectivity and catalyst stability with minimal consumption of reagents and solvents.

Selective removal of nitrate using a novel asymmetric amine based strongly basic anion exchange resin

In this study, a novel asymmetric amine-based strongly basic anion exchange resin SE-1 was synthesized successfully via the reaction of chloromethylated styrene–divinylbenzene copolymer with N, N-dimethyloctylamine. The sorption performance of SE-1 for selective removal of nitrate in aqueous solution was compared to a commercially available nitrate specialty resin, namely Purolite A 520E (A 520E). It was found that the kinetic data could be described better by the pseudo-second-order model, and SE-1 indicated a faster sorption kinetics than A 520E resin. The Langmiur model was more appropriate for explicating the sorption isotherm. Importantly, SE-1 exhibited a greater sorption capacity for nitrate regardless of the absence or presence of competing anions in solutions. The result of column tests reinforced the feasibility of SE-1 for practical application in groundwater treatment.

Thermal behavior of aminotrimethoxysilanphosphonate functionalized onto styrene-divinylbenzene copolymer

The chlorometylated styrene–divinylbenzene copolymer with different percent of divinylbenzene (code: S-6.7 DVB, S-12DVB, and S-15DVB) was functionalized with 3-hydroxybenzaldehyde for obtaining intermediated polymers. The aminotrimethoxysilanphosphonate groups were grafted by one-pot reactions in tetrahydrofuran using three components: polymers grafted with aldehyde groups (code: CHO-6.7, CHO-12, and CHO-15), 3-aminopropyltrimethoxysilane, diethylphosphite. The aminotrimethoxysilanphosphonate groups functionalized onto styrene-(6.7, 12, and 15%) divinylbenzene copolymer (code: PAF-6.7, PAF-12, and PAF-15) and evolution of the reaction were evidenced by FT-IR spectroscopy and porous structure by N2 adsorption-desorption, SEM microscopy. The thermal behavior of aldehydes and materials: PAF-6.7, PAF-12, and PAF-15 are different than initial polymer supports.

In situ functionalization of HPLC monolithic columns based on divinylbenzene-styrene-4-vinylbenzyl chloride

The properties of chromatographic columns are largely determined by functional groups located on the sorbent surface. For monolithic columns, surface functional groups can be created during synthesis stage or by chemical bonding with the complete surface of the sorbent. One of sorbent modification approach is to use on-column click reactions with surface reactive groups. In this study, the surface treatment of monolithic sorbent based on divinylbenzene (DVB), styrene (St) and 4-vinylbenzyl chloride (4VBC) copolymer by heterocyclic nitrogen-containing compounds 1-methylimidazole (1MI), 2-methylimidazole (2MI), 2-methylpyridine (2 MP) and 4-methylpyridine (4 MP) is described. The reaction of nitrogen-containing heterocycles with chloromethyl fragments on the surface results in formation of ion pairs and significantly changes the selectivity of monolithic columns. The chromatographic properties of prepared columns are studied. Modified columns can be operated in reversed-phase (RP) chromatography or in hydrophilic interaction liquid chromatography (HILIC) with different composition of the mobile phase. Separation examples of various chemical substances classes are given.

Sorption properties of new fibrous chelate ion exchanger

The sorption properties of new iminodiacetate fibrous cation exchanger FIBAN XC-1 synthesized on a chemically resistant matrix of polypropylene fiber with a grafted copolymer of styrene and divinylbenzene, which can withstand elevated temperatures and aggressive environments, were studied. It was shown that the fibrous chelate ion exchanger FIBAN XC-1 is an effective sorbent of heavy and non-ferrous metals from multi-ionic aqueous solutions under static and dynamic conditions. It was found that the cation exchanger operates at high speeds up to 20 column volumes / min in water purification from copper and lead ions (purification from Cu2+ – 82 % and purification from Pb2+– 65 %). It was found that the fibrous chelate ion exchanger FIBAN XC-1 is easily regenerated and does not lose its sorption and mechanical properties in the sorption– regeneration cycles.

A Resin-Supported Formate Catalyst for the Transformative Reduction of Carbon Dioxide with Hydrosilanes.

A heterogeneous formate anion catalyst for the transformative reduction of carbon dioxide (CO2 ) based on a polystyrene and divinylbenzene copolymer modified with alkylammonium formate was prepared from a widely available anion exchange resin. The catalyst preparation was easy and the characterization was carried out by using elemental analysis, Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and solid-state 13 C cross-polarization/magic-angle spinning nuclear magnetic resonance (13 C CP/MAS NMR) spectroscopy. The catalyst displayed good catalytic activity for the direct reduction of CO2 with hydrosilanes, tunably yielding silylformate or methoxysilane products depending on the hydrosilanes used. The catalyst was also active for the reductive insertion of CO2 into both primary and secondary amines. The catalytic activity of the resin-supported formate can be predicted from the FTIR spectra of the catalyst, probably because of the difference in the ionic interaction strength between the supported alkylammonium cations and formate anions. The ion pair density is thought to influence the catalytic activity, as shown by the elemental and solid-state 13 C NMR analyses.

One-pot synthesis, characterization and in vitro antibacterial evaluation of bioactive “aminophosphinic acid” groups grafted onto polymeric-support

In this work, the synthesis, characterization and in vitro antibacterial activity of two novel compounds with aminophosphinic acid groups have been investigated. Both α-propylaminophosphinic acid grafted on styrene-6.7%divinylbenzene copolymer (AmPhinicPr) and α-benzylaminophosphinic acid grafted on styrene-6.7%divinylbenzene copolymer (AmPhinicBz) were obtained by a one-pot Kabachnik–Fields polymer-analog reaction. They were characterized using FT-IR spectroscopy, EDX and TG/DTA, to establish the degree of functionalization with pendant α-aminophosphinic acid groups. They exhibited remarkable efficiency in antibacterial tests. The bioactive aminophosphinic groups have an antibacterial effect against Staphylococcus aureus (S.aureus), Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa) and Bacillus cereus (B. cereus). We have evaluated the applicability of the Weibull model to describe inactivation of microbial cells at our samples.

Effects of percent weight of divinylbenzene as crosslinking agent on the properties of eugenol–divinylbenzene copolymers

Synthesis of eugenol-divinylbenzene copolymers were carried out by reacting eugenol with various percent weight of divinylbenzene in a reactor at room temperature for 24 hours in the presence of sulfuric acid as a catalyst. Methanol was used to quench the copolymerization process. The effect of DVB mass on copolymer properties was studied based on molecular weight, thermal stability, surface morphology and swelling degree of the copolymers produced. The weight percent of the added DVB was responsible for the molecular weight of the copolymer by multiplying the site for propagation in the copolymerization process. In addition, the greater DVB used the better thermal resistance of polymer is obtained, which is possibly due to the higher number of DVB causing the larger cross-linked polymer network to increase the polymer bond thermal resistance. The swelling degree value was also affected by the number of crosslinkers used, in which make the polymer material become harder to expand. However, the influence of the weight percent of DVB was not seen on the copolymer morphology.

Mesoporous polymer systems based on divinylbenzene copolymers modified with linear rubbers

Porous polymer systems based on divinylbenzene copolymers modified with co-monomers (ethylvinylbenzene, methyl acrylate, methacrylic acid) and linear rubber macromolecules (polybutadiene, polyisoprene, polyisobutylene, polystyrene-butadiene, polyacrylonitrile-butadiene) were investigated. The copolymers in the form of spherical beads were synthesized by radical suspension polymerization of monomer compositions with appropriate porogenic organic solvents. It was found that modification of the divinylbenzene copolymers by linear rubbers enables the synthesis of sorbents with a controlled fractional composition of micro- and mesopores. A universal method is suggested for a quantitative estimation of fractional pore size distribution in the range of micro and mesopores from the data of low-temperature nitrogen sorption. Calculations of integral and differential distributions are based on using methods of quenched solid density functional theory (QSDFT), non-local density functional theory and the Barrett-Joyner-Halenda method based on capillary condensation theory. According to QSDFT calculations, the porous system of sorbents contains three groups of pores of certain sizes: 1.7–3.3, 3.3–6.6 and 8.4–40 nm. Upon introduction of polyisoprene into the polymer system the sorbent containing primarily 8–24 nm mesopores is obtained; upon the introduction of polyisobutylene, the sorbent with pore sizes of 4–6 nm is synthesized. The volume and surface area of micropores in the copolymers with polyisoprene and polyisobutylene may be increased by extracting a part of the rubber phase with toluene. Specific surface area of the copolymers varies in the range of 230–570 m2 g−1. Scanning electron microscopy studies of the porous structure of the polymer systems showed that in the copolymers with polybutadiene the porous structure is formed by the aggregates of globules 20–60 nm. The copolymer with polyisobutylene has a 3D skeletal structure with 100–200 nm voids.

Disposable pipette extraction phase based on styrene–divinylbenzene/pernigraniline composite, applied for dexamethasone determination in synovial fluid by HPLC with UV detector

A reliable method using disposable pipette extraction (DPX) based on composite of pernigraniline and styrene–divinylbenzene (Sty–DVB) copolymer was applied to the analysis of dexamethasone in synovial fluid using high-performance liquid chromatography and ultraviolet (UV) detector (HPLC–UV). DPX variables, namely, number of draw/eject cycles for extraction or desorption, sample pH, volume, and desorption solvent, were optimized to establish the best sorption equilibrium and analysis time. The highest extraction efficiency value was obtained with 50 μL of synovial fluid mixed with 1950 μL of water, in five cycles of 300 μL of sampling, followed by liquid desorption of the drug with 300 μL of methanol in three cycles. The developed method demonstrated a linear response over the range from 10 to 100 ng/mL, with R2 = 0.993. The limit of quantification (LOQ) was 10 ng/mL. Based on the validation results, the proposed method can be a useful tool to detect dexamethasone levels in synovial fluid.

Processes for Electrochemical Production of Electrolyte-free Hydrogen Peroxide

Hydrogen peroxide is the focus of growing attention for distributed manufacturing, reflecting its decentralized applications and shipping hazards. Two recent reports, one in Science by Wang and colleaugues and one in this issue of Joule by Surendranath, Hatton, and colleaugues, introduce innovative electrochemical methods to produce electrolyte-free aqueous solutions of hydrogen peroxide.

Highly efficient cycloaddition of diluted and waste CO2 into cyclic carbonates catalyzed by porous ionic copolymers

It is believed that porous heterogeneous materials with excellent properties are promising candidates for efficient fixation of diluted and waste CO2. Herein, a family of mesoporous porous ionic copolymers (PIPs) was designed and prepared from the copolymerization of divinylbenzene (DVB) with vinyl-functionalized ionic liquids monomers through free radical copolymerization process. It was demonstrated that the heterogeneous PIP poly(divinylbenzene-1-allyl-tetramethylguanidinium bromide) PDVB-[AlTMG]Br-0.2 showed excellent activities in facile cycloaddition of CO2 into cyclic carbonates without using any external co-catalysts or metal additives. The results of characterizations and quantum mechanical calculations further showed that the specic hierarchical meso-macroporous structure of PDVB-[AlTMG]Br-0.2 offered the strongest binding interaction with SO and besides had a relatively good CO2 affinity, which results to the best cataltic activity for cycloaddition of CO2. Moreover, PDVB-[AlTMG]Br-0.2 exhibited high activities and good reusability in cycloaddition of 15 % diluted CO2 with various epoxides. It is believed that our work would have a great potential in energy-effective fixation of industrial combustion CO2 into high-value organic carbonates.

Copolymers of vinylimidazolium-based ionic liquids and divinylbenzene for adsorption of TcO4− or ReO4−

Technetium (99Tc), a radionuclide generated from uranium fission in nuclear reactors, has posed a major threat to humans due to its long half-life and radioactivity. Therefore, it is urgent to develop a strategy of selectively and efficiently capturing of 99Tc. In this work, a series of solid copolymers (denoted as DVB-[CxClVim][Cl]) were synthesized for efficient adsorption of perrhenate (ReO4−, a surrogate for TcO4−) from mixed ions solution. The adsorbents with vinylimidazolium-based ionic liquid as functional group and divinylbenzene (DVB) as the basic framework exhibited stable structure and good ReO4−adsorption performance. The influences of the linear n-alkyl chain length on the morphology and adsorption property of the copolymers were discussed in detail. The maximum uptake of Re(VII) on DVB-[C4ClVim][Cl] was 517.61 mg·g−1. Rhenium could be separated from molybdenum in the presence of co-anions and co-cations by DVB-[C6ClVim][Cl], which demonstrated its good adsorption selectivity. The kinetic studies showed that pseudo-second-order model was more suitable for describing the behavior of Re(VII) adsorption. The adsorption mechanism was ion-exchange between Cl− and ReO4− confirmed by FI-IR, IC and XPS analysis. Additionally, DVB-[CxClVim][Cl] remained effective Re(VII) capture ability after eight adsorption/elution cycles, demonstrating their good reusability.

Development of a new ion-imprinted polymer (IIP) with Cd2+ ions based on divinylbenzene copolymers containing amidoxime groups

In this study, we synthesized a new ion-imprinted polymer (IIP) based on introduction of amidoxime groups in acrylonitrile, complexation with Cd2+ ions and polymerization with styrene and divinylbenzene by aqueous suspension polymerization. A non-imprinting polymer (NIP) was also synthesized. The adsorption tests of Cd2+ by IIP were performed by varying the pH, Cd2+ ion concentrations and contact time between the ions and the IIP. Kinetic models and adsorption isotherms were applied to evaluate the behavior of the IIP. The optimum conditions for Cd2+ adsorption by IIP were pH 6.0 and equilibrium time of 12 min. The increase in initial concentration of the Cd2+ ions resulted in an increased sorption capacity, qe. The Elovich and Freundlich were the most appropriate models to describe the sorption equilibrium and the sorption mechanism, respectively. Selectivity studies were conducted in the presence of Zn2+, Pb2+, Cu2+ and Ni2+. The selectivity results showed that the NIP was not selective for Cd2+ ions and the IIP was selective for Cd2+ ions in relation to ions of Zn2+, Cu2+ and Ni2+, but not in relation to Pb2+ ions.

Сорбционные характеристики сорбентов для твердофазной экстракции фенольных соединений из экстрактов лекарственных растений

В основе исследований настоящей работы находится твердофазное извлечение фенольных компонентов экстрактов лекарственного растительного сырья различными типами сорбционных материалов. В качестве сорбционных материалов использовали октадецилсиликагель (Strata C18-E), сополимер стирола и дивинилбензола, химически модифицированный N-винилпирролидоном,(Strata X), а также сополимер дивинилбензола и N-винилпирролидона (Oasis HLB). Для каждого из сорбентов получены сорбционные характеристики по отношению к целевым соединениям (объем до проскока, равновесный объем, объем удерживания и др.), а также десорбционные параметры (коэффициент концентрирования и степень извлечения). Показано, что сорбенты на основе октадецилсили-кагеля достаточно эффективны для извлечения группы флавоноидов и их гликозидов, а полимерные материалы - одновременно и флавоноидов, и фенольных кислот. Степени извлечения фенольных кислот и флавоноидов при коэффициенте концентрирования 5 на сорбенте Strata C18-E составили 27-40% и 79-105% соответственно. С применением сорбента Strata X также достигается концентрирова-ние в 5 раз при степенях извлечения 106-107% (для фенольных кислот) и 99-122% (для флавоноидов). На сорбенте Oasis HLB возможно концентрирование в 20 раз фенольных кислот при их степенях извлечения 74-96% и в 32 раза для флавоноидов при степенях извлечения в диапазоне 56-91%.

Suspension polymerization technique: parameters affecting polymer properties and application in oxidation reactions

Various heterogeneous polymerization techniques such as suspension, emulsion, dispersion, precipitation and seeded are employed for the synthesis of a wide variety of porous polymer particles. In present review, suspension polymerization technique is highlighted in detail with control of particle size, advantages and its applications. The aim of the review is to understand the basics of suspension polymerization for the synthesis of polystyrene cross-linked with divinylbenzene copolymer. Also, the effect of various synthesis parameters (agitation speed, temperature, initiator, cross-linker and diluent) on particle surface morphology, particle size and distribution, surface area and cross-linking density was reviewed and their application as catalyst support for various oxidation reactions.

Alkaline Ionic Liquids Immobilized on Protective Copolymers Coated Magnetic Nanoparticles: An Efficient and Magnetically Recyclable Catalyst for Knoevenagel Condensation

A novel three-layered catalyst was successfully synthesized by the copolymerization of divinylbenzene and vinyl benzyl chloride in the presence of 3-mercaptopropyltrimethoxysilane-functionalized ma...

Method Validation for the Determination of Phthalates in Indoor Air by GC-MS with Solid-Phase Adsorption/Solvent Extraction using Octadecyl Silica Filter and Styrene–Divinylbenzene Copolymer Cartridge

Method Validation for the Determination of Phthalates in Indoor Air by GC-MS with Solid-Phase Adsorption/Solvent Extraction using Octadecyl Silica Filter and Styrene–Divinylbenzene Copolymer Cartridge

Synthesis and adsorption properties of modified SDB carrier

Styrene–divinylbenzene copolymer (SDB) is a key material for preparing Pt/SDB hydrophobic catalyst, which could be used for the treatment and purification of tritiated water. In this paper, a modified SDB (MSDB) carrier based on tert-butyl styrene (t-Bu-St), methyl methacrylate (MMA), styrene (St) and divinylbenzene (DVB) was prepared by aqueous suspension polymerization. Static adsorption experiment shows that the MSDB has the best adsorption performance at the molar ratio of St, DVB, t-Bu-St and MMA of 1:0.85:0.3:0.3 with n-heptane as porogen. The adsorption behavior of MSDB is analyzed by theoretical formulas. Data show that the adsorption process is in accordance with the Lagrange pseudo-first-order kinetics and Freundlich isotherm (1/n < 1), which is exothermic and entropy decrease (ΔH0 < 0, ΔS0 < 0) in a temperature range of 293.15–333.15 K.