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Commercial ion-exchange resins (Amberlyst 35 and Amberlyst 36) and a resin synthetized in the laboratory, sulfonated poly(divinylbenzene) were evaluated as catalysts in the esterification of fatty acids (palmitic and oleic) with alcohols (methanol, ethanol and butanol). The study was developed in order to obtain a high rate of fatty acid conversion. The esterification reactions with fatty acids and methanol presented satisfactory conversion to methyl esters achieving a final conversion over 90% in both palmitic and oleic acid. A sample of waste vegetable oils with a high acid content from the residue of the palm oil and soybean oil refining industry were evaluated in the esterification with methanol. The best results were achieved with the new sulfonic resin, poly(divinylbenzene), which was synthesized in the laboratory and has proved efficient for the reaction in the study. Maximum biodiesel production was achieved from a fatty acid residue of the soybean oil refining industry and methanol (93%) which showed conversions very close to those obtained from their respective fatty acids.

The synthesis of the poly(4-vinylpyridine-co-ethylvinylbenzene) resin is investigated and its performance to remove Cr(VI) from aqueous solutions is evaluated as a function of pH using batch and fixed bed column adsorptions. The rate of Cr(VI) removal is observed to increase as the pH solution shifts to acidic conditions due to an enhanced protonation of the 4-vinylpyridine group in the polymer, which favors its electrostatic attraction with Cr(VI) oxyanions. This finding is supported with Density Functional Theory (DFT) calculations, revealing that the interaction between $${\text{CrO}}_{4}^{{2 - }}$$ (predominant species at pH 6) due to a higher charge delocalization arising in the O atoms. Experimental isotherms are approximated with the Langmuir and Radke-Prausnitz adsorption models. This former approach generates the best fitting to the data, whereby it was incorporated into a nonlinear transient model to account for the Cr(VI) adsorption in a fixed bed, and evaluating its capacity to predict experimental adsorption data. The model enables to infer that the resin presents a fast kinetic for Cr(VI) sorption, and the Cr(VI) intra-particle diffusion across the adsorbent pores is the rate-determining step for sorption.

Using magnetic hydrophilic–lipophilic balanced adsorbent (HLB), with divinylbenzene n-vinylpyrrolidone polymer as monomers and Fe3O4@C nanoparticles as magnetic material, a modified quick, easy, cheap, effective, rugged and safe (QuEChERS) method is proposed for veterinary residue analysis in milk. The magnetic Fe3O4@C-HLB adsorbent was fabricated via simple co-mixing method based on an “aggregate wrap” mechanism, which enabled magnetic solid-phase extraction. Thus, the resultant material can be separated from the solvent rapidly and conveniently by a magnet. The residues of regulatory interest in milk include β-lactams, aminoglyside, and macrolides. The analytes were quantified by ultra high-performance liquid chromatography coupled to an electrospray ionization tandem mass spectrometer operating in multiple reaction monitoring modes. The decision limit (CCα) was 0.1–0.8 µg/L, and the detection capability (CCβ) was 0.2–2 µg/L. The method was accurate with recoveries ranging from 70.5 to 98%. Good intra-precision and intermediate precision were obtained with RSD better than 10%.

Hierarchically porous carbon (HPC) materials with interconnected pore texture are produced from porous poly(divinylbenzene) precursor, synthesized by polymerizing high internal phase emulsion. After carbonation, the macroporous structures of the poly(divinylbenzene) precursor are preserved and enormous micro/mesopores via carbonation with KOH are produced, resulting in interconnected hierarchical pore network. The prepared HPC has a maximum specific surface area of 2189 m2 g-1. The electrode materials for supercapacitor and capacitive deionization (CDI) device employing the formed HPC exhibit high specific capacity of 88 mAh g-1 through a voltage range of 1V (319 F g-1 at 1 A g-1) and superior electrosorption capacity of 21.3 mg g-1 in 500 mg L-1 NaCl solution, respectively. The excellent capacitive performance could be ascribed to the combination of high specific surface area and favorable hierarchical porous structure.

Potentiometric titration of weak base anionite (the degree of crosslinking was 12–16%) was performed within the pH range of 2–12 and NaCl concentration range of 0.1–1.0 mol/L. The maximum ionexchange ability against HCl does not depend on the solution ionic strength and is 6.50 ± 0.12 mmol/g of dry solid matter. It was shown that the process of acid–base equilibrium can be adequately described by the Gregor equation within the studied stock electrolyte concentration and pH ranges. Two type of groups were discovered in anionite. The ionization constants of these groups differ by three orders of magnitude. The existence of amino groups of different nature was proved by the data obtained by functional analysis; it was estimated that the acidity of these groups decreases as NaCl concentration increases.

A series of porous polymers was synthesized by a suspension polymerization of divinylbenzene (DVB) and ethylene glycol dimethyl acrylate (EGDMA), which was further functionalized with polyethyleneimine (PEI) for CO 2 capture. The results showed that the synthesized DVB and EGDMA (DE) copolymers were an effective support for loading PEI because of its larger pore size and specific surfaces area. It was found that DE (30, 10) loaded with 30 wt% PEI exhibited a higher CO 2 adsorption amount of 3.28 mmol/g at 25 °C under dry condition. The CO 2 adsorption capacity would decline gradually as the temperature continuously raised, for the reaction between CO 2 and amine groups was an exothermic reaction. The kinetics study showed that Avrami kinetic model could accurately describe the whole CO 2 adsorption process, suggesting that both physical adsorption and chemical adsorption were involved with the CO 2 adsorption process. The intraparticle diffusion and Boyd’s film diffusion models were applied to investigate the CO 2 diffusion mechanism, the intraparticle diffusion model could well distinguish the rate-limiting step during CO 2 adsorption process. This solid amine adsorbent could be regenerated with nitrogen stream at 75 °C, and it kept stable CO 2 adsorption capacity after eight adsorption-desorption cycles. All these features indicated that this porous polymer based adsorbent has a high potential for CO 2 capture and separation from flue gas.

Coal tar pitch with a softening point (SP) of 78 °C is mixed with divinylbenzene (DVB) and then spheroidized by suspension method in dimethyl silicone oil for 1 h. During the spheroidization process, the mixtures of pitch and DVB are copolymerized due to vinyl in DVB. After vacuum-assisted heat treatment, the copolymer spheres can be stabilized completely and then carbonized directly at high temperature under Ar atmosphere without melting and deformation. After activation using steam at 850 °C for 1.5 h, spherical activated carbon (SAC) with smooth surface and specific surface area SBET = 520 m2 g−1 can be prepared. Further studies show that mesopore volume of the SAC is 0.29 cm3 g−1, which accounts for 72.5% of the total pore volume. The good spherical morphology, smooth surface and rich pores (micropores and mesopores) can be attributed to appropriate copolymerization and vacuum-assisted treatment.

Volatile organic compounds (VOCs) have been proposed in the last two decades as biomarkers for disease detection and therapeutic monitoring. Model in vitro experiments with established cell lines are fundamental to clarify whether given VOCs originate from normal human cells or pathogens, including transformed cancer cells. Due to the trace concentrations of target metabolites, adsorptive enrichment is needed before gas chromatography-mass spectrometry (GC-MS) analysis, with solid-phase microextraction (SPME) being perfectly suited for this purpose. Here, a modification of SPME, the thin-film microextraction (TFME) technique, is proposed for analysis of cellular VOCs, which utilizes a planar mesh coated with stationary phase to increase the extraction phase volume and active surface area. In this study, four different adsorbents were compared: carboxen, divinylbenzene, hydrophobic−lipophilic balanced and polydimethylsiloxane. Amongst them, HLB sheets using poly(divinylbenzene-co-N-vinyl-pyrrolidone) skeleton structure proved to be the most versatile, enabling the most sensitive analysis of VOCs with a broad polarity and volatility. For HLB, sampling type (internal static headspace, external bi-directional headspace), extraction temperature and extraction time were also examined. An established method was successfully applied to analyze metabolites produced by A549 cells revealing five volatiles at significantly higher (additionally benzaldehyde at lower) levels in cell culture medium compared to the cell-free reference medium headspace.

Developing new technologies for the reduction of SO2 emission is highly demanded. In this work, a meso-macroporous polymer was synthesized by one-step solvothermal polymerization of divinylbenzene (DVB). The synthesized polymer-polydivinylbenzene (PDVB) also has considerably large pore volume. Given these features, a series of composite sorbents with a polytertiary amine (PTA) physically immobilized in PDVB were then synthesized, and subsequently characterized and investigated for the capture of SO2 in details. The PTA loadings of composite sorbents range from 1.00 to 2.35 g/g, which are dense in the functionalization of tertiary amine groups that enable Lewis base-acid interaction with SO2. As a result, the composite sorbents exhibit excellent efficiency for SO2 capture, especially at extremely low pressures. The SO2 adsorption capacities of composite sorbents have the values of 3.86 ~ 6.88 mmol/g of SO2 at 25 °C and 0.002 bar. The composite sorbents are also excellent for the selective separation of SO2 from CO2 and N2, as well as the excellent reversibility for the adsorption of SO2.

In this study, a comparison of the efficiency of the commercially available polydimethylsiloxane/divinylbenzene (PDMS/DVB) overcoated (OC) fiber used in direct immersion (DI) or in headspace (HS), has been performed by extracting volatiles through solid-phase microextraction (SPME) from a red wine and from a wine model to confirm the results. It was also investigated if a combination of DI followed by HS in a single assay (DI-HS) can provide improvements as compared to the use in DI or in HS only. Furthermore, the use of OC fiber in HS mode was compared with the use of the triphasic phase (TP, in PDMS/CAR/DVB), known to provide good results in this application. To have information also on fiber specificity, the detected analytes were subdivided into three classes depending on their boiling point. Results show that: OC fiber gives slightly better performance as compared to TP fiber, demonstrating a high efficiency of the OC fiber also in HS mode. Then, comparing the use of the commercial OC fiber in HS, DI and in the combined DI-HS mode, explored for the first time in this study to extract volatiles from wine, the combination DI-HS resulted to provide a more balanced efficiency for all the three groups of analytes, thus being a good compromise when the analytes have a broad range of volatility. Principal component analysis (PCA) and the design of experiment (DoE) were exploited to plan experiments and to help interpreting the results, highlighting that the combined DI-HS approach can be successfully applied to the characterization of wines and of other matrices, where analytes of interest have a wide range of volatility.

Sulfonated styrene divinylbenzene/Bismuth-Tin composites were produced and stabilized with polyoxyethylene 23 lauryl ether (Brij®) as an alternative to Nafion®-metal nanocomposites. The terpolymers were synthesized by emulsion polymerization, and the metal particles were produced by reduction with sodium borohydride in a mixture of sulfonated terpolymer and Brij® assisted by ultrasound. Dynamic light scattering was used for measuring the average hydrodynamic diameter. Time stable nano emulsions of polymer-metal particles between 200 and 500 nm with no appreciable changes in size were observed. Through statistical analysis, the composition of the reactive mixture (Bi, total metal, and % Brij®) was related to the metal particle size. Selected terpolymers and composites with a total metal concentration of 13% w/w were casted and structurally characterized by means of infrared spectroscopy and X-ray photoelectron spectroscopy. The morphology and polymer-metal distribution were studied via field emission electron microscopy. For high bismuth content, clusters greater than 100 nm in diameter were observed and the increase in tin content produce discrete particles of 20–40 nm. The electrochemical behavior of the composites was studied for the detection of Cd, Cu, Zn and Pb via square-wave anodic stripping voltammetry, the electrodes had a good performance to measure only cadmium with a detection limit and sensitivity like those of Nafion-bismuth composites obtained previously. This material also presented less degradation but showed interference in the presence of the other metals.

Ag doped TiO2 (Ag-TiO2) nanophotocatalyst is prepared and embedded in porous polymer (PP) to achieve recyclability without compromising the catalytic efficiency. Porous polymer is synthesized by co-polymerization of divinylbenzene (DVB) and bismaleimide. Silver doped TiO2/porous polymer composite (PPTS) is prepared through in-situ solvothermal process. X-ray diffraction and Energy dispersive X-ray spectroscopy is used for structural and elemental analysis, respectively. Particle size and morphology is observed through Transmission Electron Microscope and Scanning Electron Microscope. Degradation ability of PPTS under xenon light as well as natural sunlight is analyzed and compared with bare TiO2 and Ag-TiO2 for degradation of methyl orange and degradation rate constant is also calculated. The mechanism of photocatalysis is explored through ESR analysis which confirmed the production of hydroxyl radicals (OH•) that is responsible for oxidation reactions and consequently degradation of pollutants. The synergistic effect originated from the higher sunlight absorption capability of Ag-TiO2 and higher adsorption of pollutant on the surface of porous polymer offered improved photocatalytic performance. The developed photocatalyst (PPTS) system can easily recovered and its photocatalytic efficiency retained almost 97% up to 10 cycles, which make the developed system a potential and the sustainable solution for pollution abatement.

Zeolite-templated carbon (ZTC) with a high surface area of 3860 m2 g−1 is readily synthesized from divinylbenzene (DVB) and propylene as carbon sources, by using NaY zeolite as a template. In the present method, the necessary amount of DVB can be reduced to the total pore volume of the zeolite. DVB can be directly mixed with previously dried zeolite, and each time for the adsorption and the thermal polymerization of DVB is shortened to only 1 h. The resulting NaY/polydivinylbenzene (PDVB) is subject to chemical vapor deposition (CVD) using propylene and the subsequent carbonization. In this process, DVB becomes graphene fragments that have a catalytic activity against propylene, and the ZTC framework with the three-dimensionally ordered and interconnected micropore structure is developed inside the zeolite pores during the CVD. Finally, zeolite is removed by HF etching, producing 0.3 g of ZTC per 1 g of zeolite. Instead of DVB, previous methods to prepare high surface area ZTCs use furfuryl alcohol that gradually polymerizes and strongly stacks on the zeolite particles, leading to a decrease in the surface area of ZTC due to the resulting nonporous carbon shell formed on the ZTC particles. The present method is much easier and more feasible than the previous methods, and does not require any reagents for polymerizing DVB or organic solvents.

Volatile compounds are the main chemical species determining the characteristic aroma of food. A procedure based on headspace solid-phase microextraction (HP-SPME) coupled to gas chromatography-mass spectrometry (GC-MS) was developed to investigate the volatile compounds of sweet potato. The experimental conditions (fiber coating, incubation temperature and time, extraction time) were optimized for the extraction of volatile compounds from sweet potato. The samples incubated at 80 °C for 30 min and extracted at 80 °C by the fiber with a divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) coating for 30 min gave the most effective extraction of the analytes. The optimized method was applied to study the volatile profile of four sweet potato cultivars (Anna, Jieshu95-16, Ayamursaki, and Shuangzai) with different aroma. In total, 68 compounds were identified and the dominants were aldehydes, followed by alcohols, ketones, and terpenes. Significant differences were observed among the volatile profile of four cultivars. Furthermore, each cultivar was characterized by different compounds with typical flavor. The results substantiated that the optimized HS-SPME GC-MS method could provide an efficient and convenient approach to study the flavor characteristics of sweet potato. This is the basis for studying the key aroma-active compounds and selecting odor-rich accessions, which will help in the targeted improvement of sweet potato flavor in breeding.

A solid-phase microextraction coupled with gas chromatography and mass spectrometry (SPME-GC–MS) method was developed to discriminate the two chemotypes of the medicinal herb Egletes viscosa. The optimization of the extraction conditions was carried out through factorial design and response surface methodology. The best conditions were achieved when the flower buds (0.33 g) using the divinylbenzene/carboxen/polydimethylsiloxane-coated fiber (DVB/CAR/PDMS, 50/30 µm) were extracted for 6.6 min at 40 °C, corresponding to an extraction time 30x shorter and a sample mass 300x lesser than the conventional method based on hydrodistillation (HD). Five out of 16 commercial samples were classified as chemotype A for presenting trans-pinocarveyl acetate as major compound (25.7–34.3%), while the others were from chemotype B for being richer in cis-isopinocarveyl acetate (27.4–62.2%). This finding is in perfect agreement with the classification provided by HD-GC–MS. Regardless of the extraction method, the volatiles constituents were basically monoterpenoids and monoterpenes, but SPME extracted more compounds than HD (33 × 24). In addition, many of them were detected only by one of the extraction methods or fiber coating. Since our SPME method demonstrated to be able to discriminate the two chemotypes in a non-destructive way providing the volatile chemical composition, it will be helpful for chemical screening and quality control of raw materials for pharmaceutical and cosmetic purposes.

Poly(styrene–divinylbenzene)-based adsorption resin has the advantages of high specific surface area, adjustable pore size and other advantages, and has been widely used in the separation and purification of natural products and sewage treatment. However, its adsorption selectivity for specific compounds is poor. Therefore, to improve the selectivity of poly(styrene–divinylbenzene), the boric acid–functionalized monodisperse poly(styrene–divinylbenzene) was synthesized by seed swelling method by adding boric acid–functionalized polymerized monomer in the swelling stage. The static adsorption results showed that this polymer was pH–responsive. When pH> 9.5, the adsorption reached the maximum, and it could be desorbed with a pH

Monolithic polymers are described as continuous and highly porous materials. They have been gaining popularity as an effective extracting phase for some sample preparation methods, due to their variety of functionalities, such as wide pH range tolerance, good permeability, and its ability to allow changes into their surface. Polypyrrole represents an interesting alternative for the modification in extraction phases due to its well related ability to perform multiple interactions, such as acid-base, π - π, ion exchange, interactions with hydrophobic affinities or polar functional groups. Among the different sample preparation techniques, solid-phase extraction (SPE) is one of the most popular and used; a miniaturized version of SPE is the disposable pipette extraction (DPX). DPX is a recent miniaturized extraction technique that usually employing silica-based sorbents inside a pipette tip (5 or 1 mL). The present study proposes the development of a monolithic extraction phase composed by styrene divinylbenzene (1:1) modified with polypyrrole for SPE and DPX techniques. The efficiency of the material was evaluated in face of the extraction of different samples and analytes, triazine herbicides in water and dexamethasone in synthetic synovial liquid by conventional and miniaturized solid-phase extraction techniques. The extractions performed by SPE and DPX presented absolute recovery values ranging from 74.8 to 105.0%, inter-day precision ranging from 0.6 to 14.0%, and limit of quantification of 0.5 and 5.0 ng.mL−1, respectively. The DPX miniaturized method exhibited results equivalent to the methods reported in the literature for extraction of dexamethasone in synovial fluid samples. Moreover, this technique proved to be quicker and cheaper than SPE, and produced fewer residual volumes, supporting the preference for green chemistry. Monolithic polymers modified with polypyrrole presented to be a feasible alternative extraction phase for miniaturized sample preparation techniques.

In the present paper, the authors investigated the adsorption of cadmium on magnetic Levextrel resin containing about 352 mg g−1 Cyanex 272 (C272) as adsorbent. Magnetic Levextrel resin (mPst-DVB-C272) was synthesized through adding Cyanex 272 and oleic acid-coated magnetite nanoparticles directly to the mixture of styrene (st) and divinylbenzene (DVB) monomers during the bead polymerization. It is a new method for preparing magnetic Levextrel resins with less organic solvents and less steps MPst-DVB-C272 was characterized with scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), thermal gravity (TG) and differential thermal gravity (DTG), and vibrating sample magnetometry (VSM). Then mPst-DVB-C272 was applied to remove cadmium. The effects of pH, initial Cd(II) concentration, and contact time on Cd(II) removal were investigated in batch experiments. The optimized pH value for the Cd(II) adsorption was 6.5. The maximum adsorption capacity was 18.77 mg g−1 for mPst-DVB-C272. The adsorption reached equilibrium within 90 min and the experimental data fit the pseudo-second-order model.

New amino-functionalized vinylbenzyl chloride/divinylbenzene-based hyper-crosslinked resins (HCLRs) were synthesized with the objective of improving the HCLR polarity and affinity to carbon dioxide and polar dyes. The HCLRs chemical structure and textural properties were investigated and correlated to the adsorption performance of the modified (XDV-NH2) and plain resin (XDV). The functionalization induced a reduction of the HCLR total porosity, while promoting the formation of a highly microporous structure with significant porosity narrower than 1 nm. Tested for CO2 adsorption at 0 degrees C and 25 degrees C, despite a reduced total porosity, the amino-functionalized XDV-NH2 resin showed up to 3 times increased adsorption capacity, higher CO2 heat of adsorption and CO2/N-2 selectivity with respect to the pristine XDV. XDV-NH2 also showed superior equilibrium and dynamic adsorption capacity of indigo carmine from solution with respect to XDV. These results demonstrate that the strategy proposed for the realization of amino-functionalized hyper-crosslinked resins is highly effective to obtain a microporous polymers with a significantly increased polar character and enhanced adsorption of CO2 and polar dyes.

In recent years, nano-sized composite particles have been developed as antibacterial agents. We investigated antimicrobial activities of sulfonated poly-(eugenol divinylbenzene) nanosilver composite coated on cotton fabric. Firstly, sulfonated poly-(eugenol divinylbenzene) was synthesized through a cationic copolymerization between eugenol and divinylbenzene, followed by sulfonation using sulfuric acid. Furthermore, the nanosilver material was synthesized by reducing silver nitrate using sodium citrate solution as a reducing agent. The composite formation has been successfully carried out through the interaction of the polymer and nanosilver. The resulting inhibition zone diameter of copolymers and composites shows moderate inhibitory activity. The data shown by SEM-EDX reveals that the spray coating method is successful in making the composites coated well on cotton fabrics. Coated cotton fabric has hydrophobic properties and exhibits good antibacterial activity against E. coli and S. aureus bacteria.

In this study, amphiphilic and porous copolymers were successfully prepared by doping a carboxylated carbon nanotube aqueous phase into a styrene and divinylbenzene oil phase, followed by a simple thermal polymerization to form high internalphase emulsions (polyHIPEs-CNTs). Hypercrosslinking and interconnecting chambers were formed with abundant open-cell pores with sizes ranging from 400 nm to 3.0 µm. Infrared spectroscopy, scanning electron microscopy, water contact angle measurements, and adsorption–desorption measurements were used to evaluate the characteristics of the material. The synthesized copolymers were demonstrated to be suitable for the separation of triazine herbicides from soil under optimized operating conditions. The maximum adsorption capacities of simazine, prometon, and prometryn were 25.4, 26.5, and 27.8 µg/g, respectively; the mean recoveries ranged from 87.56 to 97.67%, with a relative standard deviation lower than 4.5%. The polymers were stable, and the adsorption and desorption of the triazine herbicides were completed within a short period (10 min) without obvious interference. Adsorption isotherms revealed that the adsorption was co-determined by multiple effects between the adsorbents and compounds. An excellent reuse performance was observed, and the proposed polymers were believed to be potential materials for sample pretreatment in environmental science and pollutant cleaning engineering.

Aggregation-induced emission (AIE) polymeric nanoparticles (PNPs) are promising candidates for detection of nitroaromatic explosives. However, the major limitation of these AIE PNPs is the complicated synthesis and deteriorated detection accuracy because of the poor colloidal and morphological stability. This study provided a facile method to construct AIE PNPs with highly cross-linked polymer matrix for sensitive and accurate detection of nitroaromatic explosives. The highly cross-linked AIE PNPs with a ~50 nm particle size were prepared through copolymerization of divinylbenzene (DVB) and a tetraphenylethene (TPE)-based AIE luminogen, (4′-tetraphenyletheyl)pheny-3-butenylether (TPE-PBE), in a water-borne miniemulsion system. Due to the good aqueous dispersibility and highly cross-linked polymer matrix, the poly(DVB-co-TPE-PBE) NPs showed excellent solvent resistance, and sensitive and accurate detection of nitroaromatic explosives in aqueous systems, especially picric acid (PA). Moreover, a rigid poly(DVB-co-TPE-PBE) film could preserve spherical morphology after coating poly(DVB-co-TPE-PBE) NPs onto various substrates (such as filter paper and glass slide). The high surface area and loose packing of poly(DVB-co-TPE-PBE) NPs offered convenience for 2,4-dinitrotoluene to diffuse and interact with TPE-PBE units. Therefore, cost-efficient and portable poly(DVB-co-TPE-PBE)-coated test strips and film on glass slides exhibited fast response, strong quenching ability, and reusability in visual detection of liquid and volatile explosives, respectively.

In this work, poly amidoamine grafted composites were proposed as enrichment adsorption materials. The composites were synthesized by grafting poly amidoamine dendrimers onto the surface of poly (styrene–divinylbenzene-glycidylmethacrylate) beads. The number of surface functional groups and adsorption capacities of the composites were controllable by varying the generations of poly amidoamine dendrimers. Afterward, adsorption parameters and desorption eluents were optimized by using N-phosphoryl dipeptide as a target molecular. Under the optimized condition, N-phosphoryl dipeptides in aqueous could be rapidly adsorbed within 30 s, and comparatively high selectivity, enrichment efficiency and recovery efficiency were obtained at pH 3 to 7. The used adsorbents show good reproducibility after being washed by methanol solvent. Reliability of the adsorbents was demonstrated by the determination of N-phosphoryl dipeptide in drinking water samples with the efficient dispersive solid phase extraction-high performance liquid chromatography method. According to the obtained result, the adsorbent showed satisfactory repeatability (RSD ≤ 5.51) and good recoveries (90.52–102.84%).

The interest on adapting bio-derived species to polymer synthesis has been increased in the last decade. Terpenes that can be obtained by extracting from the essential oils of tree sap and citrus fruit have an important place on this subject. In this respect, β-myrcene, which is a promising linear conjugated diene, is attracting the interest of researchers. However, the free radical copolymerization of β-myrcene is difficult mainly because of concurrent Diels-Alder reactions with electron-deficient vinyl monomers via their s-cis forms. Here, we developed polyHIPEs from the high internal phase emulsions (HIPEs) of β-myrcene. For this purpose, HIPEs were prepared by using either 50 or 40 vol% of β-myrcene in the continuous phase. Meanwhile, the influence of 4-vinylbenzyl chloride (VBC), divinylbenzene (DVB), and 1,3-butanedioldiacrylate (BDDA) on the copolymerization crosslinking of β-myrcene within precursor HIPEs was explored. For this purpose, HIPEs were prepared by altering the amount of comonomers between 0 and 60 vol% of the total monomer composition. The resulting HIPEs showed excellent stability. However, crosslinking could not be achieved in all cases, due to the altered monomer composition. On the other hand, crosslinked polyHIPEs were hypercrosslinked with Friedel-Crafts alkylation method. Characterization of the resulting materials showed the Brunauer-Emmett-Teller specific surface area (δBET) of the polyHIPEs was increased from 2.25 m2 g−1 to 60.18 m2 g−1 by hypercrosslinking.

This study presents a novel mixed-mode weak cation-exchange (WCX) material. This material was prepared by means of the functionalization of a mesoporous divinylbenzene (DVB) resin with maleic acid (maleic acid-DVB), which yielded a high carboxylic moiety content resulting in WCX interactions as well as suitable specific surface area for reversed-phase interactions. After the optimization of the solid-phase extraction (SPE) protocol to enhance the selectivity of the sorbent, this material was evaluated as a novel WCX sorbent in the SPE of a group of drugs from environmental water samples. The method is based on SPE followed by liquid chromatography (LC) coupled to high resolution mass spectrometry (HRMS) with an Orbitrap analyzer, and was validated and applied for the determination of basic drugs in river, effluent and influent wastewater samples. Maleic acid-DVB sorbent yielded suitable recovery rates (57% to 89%) and an acceptable matrix effect (

PolyHIPEs prepared by polymerizing high internal phase emulsions (HIPEs) normally have a cross-linked structure, with the cross-linking providing the mechanical stability to maintain the porous structure and prevent collapse during cure and uses. The most widely investigated polyHIPE (i.e., polystyrene (PS) polyHIPE) is cross-linked with divinylbenzene (DVB), making them rigid, brittle, and environmentally unfriendly. To address this issue, tough and recyclable PS based polyHIPEs are prepared in this work using 4-vinyl-arm star-shaped poly(ɛ-caprolactone) (4vPCL) as property defining cross-linker. Comparing poly(S-co-DVB) polyHIPE, the poly(S-co-4vPCL) polyHIPE is much less brittle and friable, with its impact strength up to 3 times higher. The viscous 4vPCL promotes the formation of small voids in polyHIPEs. Moreover, the polyHIPEs are soluble in organic solvent after the PCL segments were degraded, suggesting that the cross-linking could be “removed” and the polymers are eventually recyclable. On this basis, the porous polymers could be used to continuously separate oils from the water–oil mixture. When it is used as oil absorbent, it has full preservation of both the porous morphology and the absorption capacity in the performed ten absorption/desorption cycles.

Polymer hydrogels with lignin in the form of microspheres have been synthesized and their properties were evaluated. Prior to the polymerization, hardwood lignin (Eucalyptus grandis) was modified with methacryloyl chloride, and unmodified lignin (L-N) and its methacrylic derivative (L-M) were polymerized with 2-hydroxyethyl methacrylate (HEMA) and divinylbenzene (DVB) in different ratios using suspension polymerization. The presence of characteristic functional groups in the synthesized hydrogels was confirmed using attenuated total reflectance Fourier transform infrared spectroscopy (ATR/FT-IR) and NMR. Thermal properties were determined by means of differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Swelling was studied in common organic solvents and distilled water. The shapes of the hydrogels were confirmed by scanning electron microscopy (SEM) and optical microscopy. The addition of lignin significantly increased the swelling ability of the hydrogels in water and acetone. The incorporation of methacrylated lignin into the structure of HEMA-DVB hydrogels increased their sorption of Ni(II) ions by 30 % showing that these hydrogels are a promising material for use in nickel removal and recovery, as well as contributing to a better utilization of lignin.

Molecularly imprinting polymers with high selectivity toward 29 sulfonylurea herbicides were synthesized by precipitation polymerization, using metsulfuron-methyl and chlorsulfuron as the template molecule, 4-vinylpyridine as the function monomer, divinylbenzene as the crosslinking agent, and acetonitrile as porogen. The imprinted polymers were characterized and measured by scanning electron microscopy (SEM) and equilibrium adsorption experiments. The molecularly imprinted polymers displayed specific recognition for the tested 29 sulfonylurea herbicides, and the maximum apparent binding capacity was found to be 18.81 mg/g. The synthesized polymer was used as a solid-phase extraction (SPE) column coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) for determination of the tested analytes in agro-products. Within the range of 2-100 μg/L, the tested analytes have achieved a good linear association with correlation coefficient (R2) > 0.999. The calculated limits of detection (LODs, S/N=3) as along with limits of quantification (LOQs, S/N=10) were in the ranges of 0.005-0.07 μg/L and 0.018-0.23 μg/L, respectively. Under different spiking levels, the recovery rates were ranged from 74.8% - 110.5%, and the relative standard deviation (RSDs) were < 5.3%. Finally, the feasibility of the proposed methodology was successfully applied for detection of sulfonylurea herbicides in crops, vegetables, and oils samples.

The hydrophilic-lipophilic balance (HLB) polymers are able to directly extract polar and non-polar analytes from the aqueous samples, making them very popular for analytical separation and SPE applications. However, the commonly used suspension polymerization method for preparing HLB polymers is only able to efficiently prepare HLB polymers with low or medium mol percentages of the hydrophilic monomer due to the hydrophilic monomer partitioning into the aqueous phase at higher concentrations. Thus, in this study a series of HLB polymers based on divinylbenzene (DVB) (hydrophobic) and N-vinylpyrrolidone (NVP) (hydrophilic) of widely varying hydrophilicities were prepared by the more robust monolith polymerization method. The monolith polymerization enabled the preparation of DVB-co-NVP polymer from low to high NVP percentages (0 mol% to 55 mol% NVP). The comparative adsorption and separation properties of the series of DVB-co-NVP polymer were assessed using three analytes of varying polarity: adenosine (log P = −1.5), caffeine (log P = −0.07) and p-toluidine (log P = 1.39). Interestingly, the highest binding capacity for binding polar analytes was observed for the monolith polymer prepared with the intermediate 30:70 feed ratio of NVP/DVB, due to an optimal balance of surface area and hydrophilicity. Whereas, for the separation of the non-polar analytes such as p-toluidine from polar analytes like caffeine or adenosine, the hydrophobic polymers containing the lower percentages of the polar monomer (20 mol% NVP) were superior.

Cation-exchange membranes (CEMs) were developed using a radiation-grafted polymerization method to improve HI-mediated electro-electrodialysis (EED) in thermochemical water-splitting iodine-sulfur processes. The performance of the HI-mediated reaction was improved using the developed CEMs by introducing divinylbenzene (DVB) as the crosslinker. The effects of the crosslinked CEMs on performance indices such as proton conductivity, transport number, and water permeation factor were investigated. Introducing the crosslinks improved the selectivity of H+ and water transport. The permeation mechanism of the proposed EED model was investigated to determine the role of the crosslinkers in this operation. The results indicated that even though the crosslinkers had little effect on the absorption of the HIx solution and the H+ diffusion coefficient, a notable decrease was observed in the I− diffusion coefficient. The crosslinkers inhibited swelling caused by the absorption of the HIx solution that led to volume changes known to suppress H2O permeation.