Styrene-divinylbenzene Copolymer Beads Research Articles

Sorption properties of polymeric beads and films containing tetraoctyl diglycolamide towards europium (III) ions

The article presents results obtained during investigation of Eu(III) ion removal from aqueous solutions using triacetate cellulose films and styrene-divinylbenzene copolymer beads containing tetraoctyl diglycolamide (TODGA). A simple method for manufacturing films containing up to 50 % w/w TODGA is provided. Solution acidity effect on the removal rate of Eu(III) ions was studied. Maximum removal of Eu(III) ions was obtained in nitric acid solutions with concentrations of 1-6 mol/l. Additionally, increase in the europium removal rate is also observed at pH > 2 for beads and in the pH range of 2 to 4 for films. In the former case increase in the removal rate is explained by increase in the nitrate ion concentration in the solution and Eu(NO3)3(TODGA)3 complex formation, and in the latter case – by decrease in TODGA protonation rate with рН growth. Observed trends indicate a high similarity in surface sorption mechanisms between the materials studied. Sorption equilibrium of Eu(III) ions onto the styrene-divinylbenzene copolymer beads impregnated with TODGA is adequately fitted to Langmuir sorption isotherm. The maximum sorption capacity of this material for Eu(III) removal from solutions with nitric acid concentration of 1 mol/l is 7.4 mg/g. It has been found that the maximum removal rate of Eu(III) ions by the triacetate cellulose films is achieved for TODGA content in the films ≥ 40 % w/w. The possibility of selective europium sorption from natural water using both beads and films is shown. Although cations present in natural water do not bind to sorbents studied, there is still slight deterioration in sorption properties when moving from model solutions to natural water. Complete desorption of Eu(III) ions from the film surface is achieved by washing three times with an EDTA solution, рН = 6.8. Prepared films can be reused for Eu(III) ion removal.

Development of styrene-divinylbenzene copolymer beads using QuEChERS for simultaneous detection and quantification of 13 perfluorinated compounds in aquatic samples

In this work, a reliable and affordable QuEChERS sampling method is developed for simultaneous detection and quantification of 13 perfluorinated compounds (PFCs) in aquatic products. Liquid chromatography/tandem mass spectrometry (LC-MS/MS) was used for rapid analysis and the analytes were extracted using styrene-divinylbenzene copolymer (PS-DVB). The performances of the sorbents were evaluated based upon parameters, such as recovery and matrix effect. Under optimized conditions, the limits of detection of 13 PFCs were found to be lying within the range of 0.001–0.070 μg kg−1. The application of aquatic sampling demonstrated that ultra-trace levels of PFCs were successfully detected and quantified within the range of 0.028–31.0 μg kg−1 in tilapia (Oreochromis niloticus), salmon (Oncorhynchus mykiss), mussels (Perna viridis) and clam (Ruditapes philippinarum). Compared with the solid phase extraction method, the application of PS-DVB beads as an adsorbent proved to be quicker and successful in the determination of PFCs in aquatic samples.

Erratum to: Adsorption of Heavy Metal Ions onto Surface-Functionalised Polymer Beads. I. Modelling of Equilibrium Isotherms by Using Non-Linear and Linear Regression Analysis

Styrene-divinylbenzene copolymer beads with ionic liquid-like functionalities (ILLF) covalently immobilised on the surface were synthesised and used to remove Cd(II) and Pb(II) from aqueous solutions. The dependence of adsorption behaviour on initial pH and metal ion concentration of solution was established. Higher ILLF content causes improved adsorption performance as ILLF are involved in coordination with metal ions. Experimental data were analysed by several isotherm models using non-linear and linear regressions, the goodness of fit being assessed by various error functions. Langmuir and Temkin models successfully describe Cd(II) and Pb(II) adsorption, respectively, whereas Freundlich model provides the poorest fit for adsorption of the two metal ion species. For a particular isotherm model, the best fit is offered by its non-linear or linear forms or by both of them. The adsorption of Cd(II) and Pb(II) is favourable and spontaneous. The synthesised adsorbents have potential applications in wastewater treatment.

Encapsulation of the elderberry fruit anthocyanins by spray drying

Spray-dried forms of anthocyanins were prepared in a maltodextrin matrix. The anthocyanins were extracted by maceration of elderberry fruits in 0.1 M HCl followed by extract filtration through a paper filter. The extract was partially purified by solid phase extraction in a column filled with styrene-divinylbenzene copolymer beads (Sepabeads SP859/L) or in syringe cartridges with C18 silica (BioChemMack ST, Moscow, RF) followed by re-extraction with aqueous HCl and alcohol mixtures. The procedure of reversed-phase HPLC determination of the extracted anthocyanin type is discussed in comparison to HILIC method in DIOL silica columns. The latter method was shown to be preferable to avoid systematic errors in the anthocyanin type determination. Solidphase extraction in syringe cartridges gave samples with very high anthocyanins concentration (up to 70 g of cyanidin-3-glucoside chloride equivalent). When using the copolymer sorbent, the concentration was somewhat lower: up to 27 g/l. After spray drying red powder samples with anthocyanins content more than 2% were prepared, although freeze drying gave only dark resin. The red color of the samples indicates the space separation of flavylium ions in the solid state by radicals of the maltodextrin background.

Preparation Physicochemical Characterization and Catalytic Applications of Polystyrene Ethylenediamine Tetra acetic Acid Cu(II) Metal Complex

Chloromethylated styrene-divinylbenzene copolymer beads with 8% crosslink were chemically modified by reaction with Ethylenediaminetetraaceticacid leading to the incorporation of nitrogen as ligating site on the surface of the polymer. The polymeric ligand on treatment with a solution of Copper chloride gave the corresponding metal complex. The polymer supported Cu(II) complex was characterized by elemental analyses, IR,GC-MS, scanning electron micrographs (SEM). The oxidation of various alcohols such as benzyl alcohol, 2-butanol, and 2-propanol was investigated using the supported metal complexes in presence of molecular oxygen as the oxidant. The swelling studies were done by using different solvents. Kinetic data indicate that the catalysts could be recycled without significant degradation of polymer matrix.

Granular iron oxide adsorbents to control natural organic matter and membrane fouling in ultrafiltration water treatment

Fine iron oxide particles (IOPs) are effective in removing natural organic matter (NOM) that causes membrane fouling in water treatment, but the separation of used IOPs is problematic. This study focused on the fabrication and use of granular iron oxide adsorbents, in combination with ultrafiltration (UF) membranes while investigating the NOM removal efficiency and fouling control. Sulfonated styrene-divinylbenzene copolymer beads were coated with two types of iron oxides (ferrihydrite and magnetite) and their performances were compared to that of fine IOPs. A significant amount of iron oxide coating (52–63 mg of Fe per g bead) was achieved by means of electrostatic binding and hydrolysis of iron ions. Iron oxide coated polymer (IOCP) beads were able to remove some amounts (∼20%) of dissolved organic carbon (DOC) comparable to that achieved by IOPs within a short period of time (<15 min). Regenerated IOCPs exhibited the same sorption capacity as the fresh ones. The integrated IOCP/UF system operation with a 15-min empty bed contact time and 10-h cyclic regeneration maintained the 20% DOC removal with no sign of significant membrane fouling. In contrast, a sharp transmembrane pressure buildup occurred in the UF system when no iron oxide pretreatment was applied, regardless of the types of membranes tested. Iron oxide adsorbed the NOM fraction with molecular weights of >1000 kDa which is believed to be responsible for severe UF fouling.

Preparation of polymer anchored Pd-catalysts: Application in Mizoroki–Heck Reaction

A series of polymer anchored Schiff bases were prepared from chloromethylated styrene–divinylbenzene copolymer beads and loaded with PdCl 2 to get air and water stable supported catalysts. The catalysts were characterized and utilized in Mizoroki–Heck reaction of aryl bromides and iodides.

Effects of crosslinking agents and inert diluents on the characteristics of crosslinked polystyrene copolymers

AbstractThe suspension copolymerization of styrene with various vinyl crosslinking monomers, that is, dimethacrylates and divinylbenzene, was carried out with poly (vinyl alcohol) as the suspending agent. The effect of the crosslinking monomers on the characteristics of the styrene copolymers was also studied, and the styrene–divinylbenzene copolymers were found to be the most thermally stable. Inert diluents were added during styrene and divinylbenzene copolymerization to achieve porous, crosslinked polystyrene. Furthermore, the influence of the diluents on the formation of porous styrene–divinylbenzene copolymers was investigated by surface area, pore volume, pore diameter, apparent density, swelling percentage, and compressive strength measurements and the surface morphology. It was observed that among the inert diluents studied, cyclohexanol was the most effective diluent, leading to the styrene–divinylbenzene copolymer beads with maximum porosity. A surface morphology study of the polystyrene copolymer beads supported the porosity in these copolymers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Mordanting of mercury on styrene-divinylbenzene copolymer beads from aqueous solutions

The sorption of mercury ions from aqueous solutions on styrene-divinylbenzene copolymer beads (St-DVB) has been investigated for the decontamination of mercury from aqueous media. Various physico-chemical parameters, such as selection of appropriate electrolyte, contact time, amount of adsorbent, concentration of adsorbate, effect of diverse ions and temperature were optimized to simulate the best conditions which can be used to decontaminate mercury from aqueous media using St-DVB beads as an adsorbent. The radiotracer technique was used to determine the distribution of mercury. The highest adsorption was observed at 0.001 mol L−1acid solutions (HNO3, H2SO4and HClO4) using 0.2 g of adsorbent for 5.14×10−5mol L−1mercury concentration in five minutes equilibration time. Studies show that the adsorption decreases with the increase in the concentrations of all the acids. The adsorption data follows the Freundlich isotherm over the mercury concentration range of 2.19×10−4to 5.90×10−3mol L−1. The characteristic Freundlich constants,i.e.1/n= 0.42±0.01 andA= (1.54±0.03)×10−3mol g−1have been computed for the sorption system. The sorption mean free energy from Dubinin–Radushkevich isotherm is 11.9±0.1 kJ mol−1indicating ion-exchange mechanism of chemisorption. The uptake of mercury increases with the rise in temperature. Thermodynamic parameters,i.e.ΔG, ΔSand ΔHhave also been calculated for the system.

Sorption Potential of Styrene‐Divinylbenzene Copolymer Beads for the Decontamination of Lead from Aqueous Media

The decontamination of lead ions from aqueous media has been investigated using styrene‐divinylbenzene copolymer beads (St‐DVB) as an adsorbent. Various physico‐chemical parameters such as selection of appropriate electrolyte, contact time, amount of adsorbent, concentration of adsorbate, effect of foreign ions, and temperature were optimized to simulate the best conditions which can be used to decontaminate lead from aqueous media using St‐DVB beads as an adsorbent. The atomic absorption spectrometric technique was used to determine the distribution of lead. Maximum adsorption was observed at 0.001 mol L−1 acid solutions (HNO3, HCl, H2SO4 and HClO4) using 0.2 g of adsorbent for 4.83×10−5 mol L−1 lead concentration in two minutes equilibration time. The adsorption data followed the Freundlich, Langmuir, and Dubinin‐Radushkevich (D‐R) isotherms over the lead concentration range of 1.207×10−3 to 2.413×10−2 mol L−1. The characteristic Freundlich constants i.e. 1/n=0.164±0.012 and A=2.345×10−3±4.480×10−5 mol g−1 have been computed for the sorption system. Langmuir isotherm gave a saturated capacity of 0.971±0.011 mmol g−1, which suggests monolayer coverage of the surface. The sorption mean free energy from D‐R isotherm was found to be 18.26±0.75 kJ mol−1 indicating chemisorption involving chemical bonding for the adsorption process. The uptake of lead increases with the rise in temperature. Thermodynamic parameters i.e. ΔG, ΔH, and ΔS have also been calculated for the system. The sorption process was found to be exothermic. The developed procedure was successfully applied for the removal of lead ions from real battery wastewater samples.

A simple method for estimating parameters representing macroporosity of porous styrene–divinylbenzene copolymers

AbstractA quick, easy, and novel method to estimate pore volume (PV), pore size distribution, surface area (SA), and swelling coefficient in acetone (SCa) of porous styrene–divinylbenzene copolymer beads on the basis of their density (d) in dry state is developed. The density is determined by measuring cylinder method. The equation to calculate the parameters are 11.993 d2 − 14.04 d + 4.2 for PV, 68.449 ln(PV) + 208.08 for SA, and 136.47 e−1.8323(PV) for SCa. Regression analysis shows a close match between the estimated values and the corresponding values measured by mercury porosimetry, with square of the Pearson product moment correlation coefficient through data points in known y's and known x's (R2) values in the range of 0.93–0.99. The pore size distribution can be estimated from the given curves for the corresponding pore volume value. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3565–3570, 2006

How to maintain the morphology of styrene-divinylbenzene copolymer beads during the sulfonation reaction

This work aims to describe the use of acetyl sulfate as sulfonating reagent of microporous beads based on styrene (STY) and divinylbenzene (DVB) which were prepared by aqueous suspension copolymerization. The copolymer was chemically modified by two different sulfonating agents, namely sulfuric acid and acetyl sulfate which is prepared “in situ” by mixing acetic anhydride and sulfuric acid. The morphologic features of resin beads were analyzed by optical microscopy (OM) and by scanning electron microscopy (SEM). The sulfonic group incorporation into the copolymer network was verified by infrared spectroscopy (FTIR) and quantified by using a standardized NaOH solution. The bead morphology maintenance depends on the sulfonating agent and reaction conditions.

Catalytic oxidation of alkanes and alkenes by polymer-anchored amino acid–ruthenium complexes

Abstract A synthetic strategy was developed to anchor an amino acid, l -valine, on to chloromethylated styrene–divinyl benzene co-polymer beads with 6% and 8% cross-linking. The polymeric ligands containing bidentate N,O donor sites were treated with a solution of ruthenium(III)chloride to form the metal complex on the support. These immobilized Ru(III) complexes were characterized by elemental analyses, FT-IR, ESR, SEM and thermal analysis. Physico-chemical properties of the supported catalysts were also studied. The catalytic oxidation of cyclohexane and toluene were investigated using the catalysts in presence of tert -butyl hydroperoxide as the terminal oxidant at ambient and at 45 °C. In the case of cyclohexane the formation of cyclohexanol and cyclohexanone were observed. Benzaldehyde was selectively obtained with toluene as substrate. The catalysts are also active in the epoxidation of olefins such as styrene and norbornylene. Recycling studies indicate that the catalyst can be recycled three to four times without significant degradation of polymer matrix. The probable mechanistic pathway has been described.

A new method to estimate pore volume of porous styrene–divinylbenzene copolymers

A new method to estimate the pore volume of porous styrene–divinylbenzene copolymer beads is proposed. The estimated pore volume (PV e) is based on the solubility parameters ( δ i ) and the corresponding weight fractions ( f i ) of styrene, divinylbenzenes and diluents in the polymerization mixture. The equation used is: PV e = 1.136 ∑δ if i 2− 21.193∑δ if i+ 98.825 . Regression analysis results show that an ideally close match of the predicted pore volume and the pore volume determined by mercury porosimeter is achieved with R 2=0.99, when non-polar and moderately polar liquids are employed as diluents. In the case of strongly polar (H-bonding) liquids as diluents, the method should be used only to predict a trend towards an increase or decrease in pore volume, which occurs as a result of variation in the composition of polymerization mixture.

Catalytic epoxidation of olefins by polymer-anchored amino acid ruthenium complexes

A synthetic strategy was developed to anchor an amino acid l-valine on to styrene–divinylbenzene co-polymer beads with 8% and 6% cross linking. The polymeric ligands containing bidentate N,O donor sites were treated with a solution of ruthenium(III) chloride to form the metal complex on the support. These immobilized Ru(III) complexes were characterized by elemental analysis, FT-IR, UV–visible diffuse reflectance, ESR, SEM and thermal analysis. The catalytic epoxidation of styrene, norbornylene, cyclooctene, and cyclohexene were investigated using the supported catalysts in the presence of tert.-butyl hydroperoxide as the terminal oxidant. Selective epoxide formation was observed with norbornylene and cis-cyclooctene whereas in the case of styrene the corresponding epoxide, benzaldehyde and acetophenone were obtained. Amongst the olefins screened, good activity was observed in the case of cyclohexene. The effect of various reaction parameters as well as some aspects of catalyst recycling and possible mechanistic pathways has also been investigated.

High-performance liquid chromatographic separation of carbohydrates on a stationary phase prepared from polystyrene-based resin and novel amines

New anion-exchange stationary phases O n ( n=1, 2 and 3) with a dimethylamino terminal functional group, where n is the number of oxyethylene units [–(CH 2CH 2O) n –], were prepared by the reaction of chloromethylated porous styrene–divinylbenzene copolymer beads and amines [(CH 3) 2N–(CH 2CH 2O) n CH 2CH 2–N(CH 3) 2]. HPLC separations of monosaccharides (sorbitol, fucose, glucosamine, mannose, glucose, galactose, fructose, allose and altrose) and disaccharides (trehalose, lactose, cellobiose and maltose) were performed successfully on these stationary phases. The ether group of the stationary phases O n was found to affect the separation of carbohydrates.

Analysis of single polymer beads for solid phase combinatorial synthesis: the determination of reactive thiol and within batch polydispersity of bead loadings.

Polymer beads are the starting point of many synthetic protocols, and in a number of combinatorial syntheses such studies are based on single beads. It has therefore become important that individual beads carry the same functional group activity and quality control of populations of beads requires a knowledge of the distribution of activity between the individual beads. A procedure was developed for the measurement of the thiol loading of single copolymer beads which is based on the bleaching of Michler's hydrol [4,4'-bis(dimethylamino)-diphenylcarbinol (BDC-OH)]. Flow injection colorimetry permits the small volumes of solution generated from single beads to be measured with rapid turnover and with a reproducibility of ca. 2%. The solution detection limit of 0.17 mM corresponds to a bead thiol concentration of 0.33 mmol g-1. The procedure and the variability of a bead population were demonstrated using modified styrene-divinylbenzene copolymer beads. The apparatus allowed fast, simple and accurate determinations to be carried out on the individual polymer beads. Within a single batch of thiol-modified styrene-divinylbenzene beads thiol loadings ranged from < 0.35 to 2.07 mmol g-1 or 0.12 to 1.3 mumol per bead. Polydispersity may therefore significantly influence screening decisions based on single bead syntheses.

Unusual mobility of hypercrosslinked polystyrene networks: Swelling and dilatometric studies

Hypercrosslinked polystyrene samples were prepared by an intensive postcrosslinking of highly swollen styrene–divinylbenzene copolymer beads to extremely high degrees of crosslinking that amounted to 100% or even higher. When in the dry state, the materials obtained represent transparent beads of reduced density. Despite the high degree of crosslinking, the materials manifest large increases in volume on swelling with any liquid media as well as large changes in volume on heating. The factors determining the unusual swelling ability of the hypercrosslinked polymers are briefly discussed. Thermodilatometric tests of the polymers with a moderate degree of crosslinking reveal a certain contraction of the beads at temperatures higher than 100 °C. When crosslinked far beyond 100%, the networks demonstrate unusual expansion in the 100–220 °C range; this is followed by a sharp shrinking at higher temperatures. The former is caused by an increased intensity of the vibration movements of the network and a partial relaxation of strong inner stresses; the latter is due to partial chemical oxidation, degradation of network units, or both. This degradation, however, is not accompanied by any loss in weight of the polymer but only results in a transformation into a more dense conventional nonporous material. The strained, rigid open-work structure of the homogeneous expanded hypercrosslinked polystyrene networks is responsible for their unusual mobility. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1553–1563, 2000

Synthesis and catalytic property of poly(styrene- co-divinylbenzene) supported ruthenium(III)-2-aminopyridyl complexes

Chloromethylated styrene-divinylbenzene copolymer beads with 8 and 14% cross-link were chemically modified by a reaction with 2-aminopyridine leading to the incorporation of nitrogen ligating sites on the surface of the polymer. These polymeric ligands, on treatment with a solution of ruthenium(III) chloride, gave the corresponding metal complex. The polymer supported Ru(III) complexes were characterized by elemental analysis, FT-IR, diffuse reflectance, SEM and DTA-TGA methods. The epoxidation of cis-cyclooctene, cyclohexene and styrene was investigated using the supported metal catalysts in presence of tert-butyl hydroperoxide as the terminal oxidant. Cis-cyclooctene gave the corresponding epoxide in a maximum yield of 51% whereas in case of styrene both styrene oxide and secondary oxidation product benzaldehyde were obtained in a combined yield of 95% under similar conditions. Surprisingly with cyclohexene as substrate the major product was 2-cyclohexene-1-one (64%) compared to the epoxide (2 %).

Preparation of macroporous, monodisperse, functionalized styrene–divinylbenzene copolymer beads: Effect of the nature of the monomers and total porogen volume on the porous properties

The staged templated suspension polymerization method was used for the preparation of 5 μm beads from mixtures of styrene and several substituted styrene monomers, including 4-methylstyrene, 4-aminostyrene, 3-aminostyrene, 4-acetoxystyrene, and 4-tert-butoxycarbonyl oxystyrene, with divinylbenzene in the presence of various amounts of linear polystyrene and dibutyl phthalate as porogens. The nature of the monomer as well as the total percentage of porogenic compounds in the polymerization mixture have a large effect on the porous properties and surface morphology of the monodisperse beads. Beads with large pores can only be obtained once the percentage of porogen in the mixture exceeds a threshold value that varies with the type of monomers involved in the polymerization. The level of incompatibility of the functional polymer chains formed during the crosslinking polymerization with the linear polystyrene porogen that is present in the polymerization mixture is another variable that also affects both the porous properties and the morphology of the beads. Because better compatibility is achieved, this effect is less pronounced if unfunctionalized styrene is used as a monomer. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67: 597–607, 1998