Divinylbenzene Research Articles

Anion-rich porous poly(ionic liquid)s for efficient CO2 conversion into cyclic carbonates through hydrogen bonding synergistic effect

Ionic liquids have widely been recognized as highly effective catalysts for the synthesis of cyclic carbonates from CO2 and epoxides. However, the cumbersome separation process hinders the practical application of these catalysts. In this study, a strategy involving free radical polymerization was employed to successfully co-polymerized monomers of ionic liquid and divinylbenzene (DVB), resulting in the fabrication of anion-rich porous poly(ionic liquid)s (PILs) that incorporated a hydrogen bonding site of -NH2-+. The texture properties of the as-prepared PILs were characterized in detail, and they were then utilized as catalysts for the cycloaddition of CO2 and epoxides to form cyclic carbonates. Remarkably, the reaction exhibited a remarkable yield of up to 99 % under solvent- and metal-free conditions. It is noteworthy that PIL-2 demonstrated easy recoverability, with a slight reduction in catalytic activity of about 7 % after five cycles. Additionally, a mechanism based on hydrogen bond synergistic for the conversion of CO2 by anion-rich porous PILs was proposed. This study offers a valuable insight for the development of recyclable poly(ionic liquid)s catalysts for CO2 conversion.

Nano-turbostratic carbon-decorated SiOC ceramic aerogels with ultra-broadband electromagnetic wave absorption properties

As thermal insulation-electromagnetic wave absorption (EMA) integrated materials, ceramic aerogels’ thermal properties have been extensively investigated, whereas their EMA properties have not. In this work, nano-turbostratic carbon-decorated SiOC ceramic aerogels were fabricated by pyrolyzing polysiloxane modified with divinylbenzene (DVB). Investigations were conducted into the effects of DVB content on the compositions, microstructures, and EMA properties of SiOC ceramic aerogels. Our research uncovered that SiOC ceramic aerogels contained ultrafine nano-turbostratic carbons (around 5 nm), resulting in abundant interface and defect polarizations. SiOC ceramic aerogels with excellent EMA properties at both small (<5 mm) and large (up to 40 mm) thicknesses were obtained by adjusting the DVB content. The reflection loss and effective absorption bandwidth of SiOC ceramic aerogels were -65.6 dB and 6 GHz at a sample thickness of 2.45 mm, while the effective absorption bandwidth widened to 11.2 GHz at 40 mm. The EMA mechanism of SiOC ceramic aerogels was discussed.

Diamide-linked imidazolyl Poly(dicationic ionic liquid)s for the conversion of CO2 to cyclic carbonates under ambient pressure

The ionic active centers and hydrogen-bond donors (HBDs) in heterogeneous catalytic materials are highly beneficial for enhancing the interaction between solid–liquid-gas three-phase interfaces and promoting effective fixation of carbon dioxide (CO2). Diamide-linked imidazolyl poly(dicationic ionic liquid)s catalysts PIMDILs (PMAIL-x and PBAIL-2) were synthesized through the copolymerization of diamide-linked imidazolyl dicationic ionic liquids (IMDILs) with divinylbenzene (DVB), which successfully enable the simultaneous construction of high-density and uniformly distributed ionic active centers (2.014–4.883 mmol g−1) and hydrogen-bond donors (HBDs). The as-synthesized PIMDILs present excellent catalytic activity in promoting the cycloaddition of CO2 with epoxides. PMAIL-2 could convert epichlorohydrin (ECH) with a quantitative conversion of 99.8 % (selectivity > 99 %) under ambient pressure. Furthermore, only a decrease in activity of 5 % was observed even after six cycles of recycling. The excellent conversions (>97.3 %) were achieved for various terminal substituted epoxides. The experimental and characterization results reveal that the high-density ionic active centers and amide HBDs can effectively activate the reaction substrates, their synergistic effect plays a crucial role at the catalyst interface. This work is expected to provide some useful insights for the rational construction of heterogeneous catalysts for CO2 conversion.

Facile construction of heterogeneous dual-ionic poly(ionic liquid)s for efficient and mild conversion of CO2 into cyclic carbonates

In the context of peaking carbon dioxide emissions and carbon neutrality, development of feasible methods for converting CO2 into high value-added chemicals stands out as a hot subject. In this study, P[D+COO−][Br−][DBUH+], a series of novel heterogeneous dual-ionic poly(ionic liquid)s (PILs) were synthesized readily from 2-(dimethylamino) ethyl methacrylate (DMAEMA), bromo-substituted aliphatic acids, organic bases and divinylbenzene (DVB). The structures, compositions and morphologies were characterized or determined by nuclear magnetic resonance (NMR), thermal gravimetric analysis (TGA), infrared spectroscopy (IR), scanning electron microscopes (SEM), and Brunauer-Emmett-Teller analysis (BET), etc. Application of the P[D+COO−][Br−][DBUH+] series as catalysts in converting CO2 into cyclic carbonates showed that P[D+COO−][Br−][DBUH+]-2/1/0.6 was able to catalyze epiclorohydrin-CO2 cycloaddition the most efficiently. This afforded chloropropylene carbonate (CPC) in 98.4% yield with ≥ 99% selectivity in 24 hr under solvent- and additive-free conditions at atmospheric pressure. Reusability experiments showed that recycling of the catalyst 6 times only resulted in a slight decline in the catalytic performance. In addition, it could be used for the synthesis of a variety of differently substituted cyclic carbonates in good to excellent yields. Finally, key catalytic active sites were probed, and a reasonable mechanism was proposed accordingly. In summary, this work poses an efficient strategy for heterogenization of dual-ionic PILs and provides a mild and environmentally benign approach to the fixation and utilization of carbon dioxide.

Construction of Ultrastable porous carbons materials derived from organic/inorganic double decker silsesquioxane (DDSQ) hybrid as a high-performance electrode for supercapacitor

Three different types of organic/inorganic hybrids are synthesized through the hydrosilylation of the double-decker silsesquioxane (DDSQ) with divinylbenzene (DVB), 3,13-divinyl double-decker silsesquioxane (DV-DDSQ) and cubic octavinylsilsesquioxane (OVS) individually to form DVB-DDSQ, DVDDSQ-DDSQ, and OVS-DDSQ, was achieved through Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy. Thermal stability using TGA analyses, it was observed that the OVS-DDSQ hybrid possesses the highest thermal stability with Td10 of 596 °C and a char yield of 82.2 wt% because of the improvement of the cross-linking structure and increased density within the OVS-DDSQ hybrid. Furthermore, after carbonization to increase the surface area of OVS-DDSQ to form a microporous carbon (C-OVS-DDSQ) hybrid framework, it displays electrochemical performance with specific capacitances of 146 F g−1 at 0.5 A g−1, benefiting from its high surface area of 169 m2 g−1, which facilitated efficient electron transfer and the presence of a lot of active sites on the electrode surface. Notably, the capacitance retention of the C-OVS-DDSQ hybrid remained excellent, reaching 98 % at 20 A g−1 even after 5000 cycles, suggesting its remarkable stability.

Zinc(II) porphyrin-based ionic porous organic polymers (iPOPs) having abundant dual-function sites for promoting cycloaddition of CO2 with epoxides

A series of zinc(II) porphyrin-based ionic porous organic polymers [ZnTPyPBr4/DVB(1:m)-iPOP (m = 10, 20, 30, 40)] were synthesized by the free-radical copolymerization of pyridinium–functionalized Zinc(II) porphyrin (ZnTPyPBr4) and divinylbenzene (DVB) through solvothermal method and characterized successfully. The iPOPs had high specific surface areas, relative high CO2 adsorption capacity, abundant dual-function sites (Zn and Br-) and high catalytic efficiency for the cycloaddition reaction of CO2 and epoxides under mild conditions (80 ℃，0.5 MPa CO2). In particular, ZnTPyPBr4/DVB(1:30)-iPOP displayed the highest catalytic activity with a conversion of 99 % for the cycloaddition of CO2 and epichlorohydrin, wide applicability for different epoxides and could be recycled five times with almost no loss of activity. Notably, the kinetic experiments demonstrate that ZnTPyPBr4/DVB(1:30)-iPOP exhibited a low activation energy (22.64 kJ mol−1) for the cycloaddition reaction of CO2 and epichlorohydrin in the absence of solvent and cocatalyst.

Fabrication and mechanism of microspheres with tunable and control-released hydrophobicity: Ultra-low-density proppants

Ultra-low-density proppants with tunable and control-released hydrophobicity can meet different requirements of different fracture environments, thus playing an important role in unconventional reservoir exploration. In this study, for the first time, we designed and synthesized proppants with a molecular structure of γ-methacryloxypropyltrimethoxysilane (KH570)-styrene (St)-divinyl benzene (DVB) (FR-SDB) through suspension polymerization. FR-SDB was examined by Fourier-transform infrared spectroscopy, atomic force microscopy, scanning electron microscopy, and X-ray diffraction to understand the mechanism of tunable and control-released hydrophobicity. The results revealed that the hydrophobicity is related to the hydration reaction of chemically bonded KH570 and the difference in the reaction activities under different aqueous environments at different temperatures. The wettability of FR-SDB was evaluated according to the static water contact angle (θw) on its surface. The contact angle θw on the surface of FR-SDB can be tailored from the initial angle of approximately 50° to 80°–125° in a wide time range of 10 min to 144 h. FR-SDB exhibited ultra-low apparent density of approximately 1.028 g/cm3, high compressive strength, and a crushing ratio of ∼ 1.81% at closure pressure of 69 MPa.

High temperature stable, amorphous SiBCN microwave absorption ceramics with tunable carbon structures derived from divinylbenzene crosslinked hyperbranched polyborosilazane

Currently, polymer-derived ceramics (PDCs) often achieve electromagnetic (EM) wave attenuation by in situ generation of nanocrystals. In this paper, amorphous monolithic siliconboron carbonitride (SiBCN) ceramics with outstanding microwave absorption property were prepared via pyrolysis of hyperbranched polyborosilazane crosslinked with divinylbenzene (DVB). The crosslinking of DVB increases the ceramic yield and the sp2 carbon contents, which facilitates the formation of multiple ordered carbon structures and enhances the dielectric loss and microwave absorption property of ceramics. By regulating DVB content and pyrolysis temperature, the amorphous SiBCN ceramics with ordered carbon structures exhibit optimized microwave absorption performance with a minimum reflection coefficient (RCmin) of −54.24 dB and a maximum effective absorption bandwidth (EABmax) of 3.15 GHz. Further, when the planar sample is tested using arch method, the practical RCmin value is −14.86 dB at 14.46 GHz and the EABmax is up to 6.4 GHz (11.6 GHz–18 GHz). In addition, the amorphous SiBCN has excellent high temperature resistance, no mass change in nitrogen (N2) and only 3.23% mass loss in air until 1400 °C. The high temperature stable, amorphous SiBCN microwave absorption ceramics provide a new strategy to the preparation of microwave absorption materials.

The Effect of Divinylbenzene on the Structure and Properties of Polyethylene Films with Related Radiation Chemical Grafted Polystyrene and Sulfocationite Membranes.

In the present work, the effect of divinylbenzene (DVB) on the kinetics of post-radiation chemical graft polymerization styrene (St) on polyethylene (PE) film and its structural and morphological features were investigated. It has been found that the dependence of the degree of polystyrene (PS) grafting on the DVB concentration in the solution is extreme. An increase in the rate of graft polymerization at low concentrations of DVB in the solution is associated with a decrease in the mobility of the growing chains of PS. A decrease in the rate of graft polymerization at high concentrations of DVB is associated with a decrease in the rate of diffusion of St and iron(II) ions in the cross-linked network structure of macromolecules of graft PS. A comparative analysis of the IR transmission and multiple attenuated total internal reflection spectra of the films with graft PS shows that graft polymerization of St in the presence of DVB leads to the enrichment of the film surface layers in PS. These results have been confirmed by the data on the distribution of sulfur in these films after sulfonation. The micrographs of the surface of the grafted films show the formation of cross-linked local microphases of PS with fixed interfaces.

Early bird gets the network: The relative importance of reactivity ratios, Ψ parameter, and crosslinker level on gel formation in FRP

AbstractNetwork topology is manipulated in free‐radical copolymerization via proper selection of crosslinker type and its respective properties when paired with specific monomers. Our prior work has focused on the impact of the reduced reactivity parameter Ψ applied to a pendent vinyl, characteristic for each monomer/crosslinker pair, yet here we assess the relative importance of the comonomer reactivity ratios to see whether one factor can counterbalance the other. The traditional reactivity ratio determines when the crosslinker molecule is incorporated into the polymer backbone, while the reduced reactivity Ψ parameter relates to the efficiency of the resulting pendent side chain vinyl being utilized to form a crosslink node at some later point during the polymerization. Both factors are then contrasted with simply the overall loading of crosslinker. Either n‐butyl methacrylate (n‐BMA) or styrene (STY) was chosen as a primary backbone monomer to copolymerize with one of three crosslinkers: 1,4‐butanediol dimethacylate (BDDMA), 1,4‐butanediol diacrylate (BDDA), or divinylbenzene (DVB). Both kinetics and gel can be most dramatically boosted when a crosslinker is applied having a reactivity ratio favouring early insertion. This in turn leads to an earlier onset of gel formation, which ultimately results in greater final gel content. This amplification of both kinetics and gel can overcome an otherwise small Ψ due to crosslinker or main monomer choice. This reactivity ratio effect was further confirmed by Monte Carlo simulations. By whatever mechanism (higher Ψ, lower rA, or higher crosslinker level), earlier onset of gelation produces more gel overall and a tighter network topology.

Development of biomimetic hexapeptide functionalized monolithic material for capillary microextraction of microcystins in environmental waters

In this work, a histidine-tagged hexapeptide functionalized monolithic material is described for the efficient capillary microextraction (CME) of microcystins (MCs) from environment waters. 1-Vinylimidazole (VIM) monomer was utilized to synthesize the matrix polymer monolith by the copolymerization with divinylbenzene (DVB) crosslinker in the presence of radical initiator azobisisobutyronitrile (AIBN). The affinity sorbent was then prepared by a metal ion chelation-based multi-step approach, in which the histidine tag peptide Trp-His-Trp-Leu-Gln-Trp (WHWLQW) was functionalized on a Cu2+ modified polymer monolith via a chelation reaction between the imidazole group of histidine and Cu2+. The resultant WHWLQW functionalized monolithic material had high affinity, hierarchical porosity and good mechanical stability. Especially, it exhibited favorable enrichment capacity for MCs compared to other affinity materials as previously reported. With the optimized CME protocol, MCs at ultra-trace level can be analyzed by CME coupled to high performance liquid chromatography-mass spectrometry (HPLC-MS) in different aqueous environmental matrices. The average recoveries were ranged from 89.3% to 104.5% with relative standard deviations (RSD%) of 2.1–8.4, demonstrating high extraction efficiency and repeatability. The limits of detection (LODs) of MCs were determined to be 0.28–0.45 ng L-1. This novel biomimetic sorbent shows promising potential for the enrichment of ultra-trace pollutants in environment waters.

Facile preparation of isocyanate-functionalized poly(styrene-co-maleimide-co-maleic anhydride) particle and its application as a versatile support for nano-sized TiO2 photocatalyst

Polymer-supported catalysts have attracted intensive research attentions due to easy handling, facile separation and outstanding recycling performance. Herein, a simple, efficient and universal strategy was developed to fabricate isocyanate-functionalized polymer microspheres bearing highly reactive surface isocyanate groups, which could serve as a versatile support for the immobilization of photocatalyst. Firstly, self-stabilized precipitation polymerization of maleimide, maleic anhydride and styrene was performed in the presence of divinyl benzene (crosslinker) to prepare imide-functionalized poly(styrene-co-maleimide-co-maleic anhydride) (PSMM) microspheres. By simply adjusting the solvent composition and monomer feed ratio, monodisperse PSMM particles with diameter in the range of 0.52–1.01 μm were successfully obtained, which were further modified with hexamethylene diisocyanate (HDI). As a proof-of-concept, TiO2 nanoparticles were readily and covalently bound to the surface of HDI-functionalized PSMM (PSMM-HDI) particles through reaction with isocyanate groups, leading to the formation of PSMM-HDI supported TiO2 (PSMM-HDI@TiO2). Furthermore, anhydride groups on the surface of PSMM was hydrolyzed to endow PSMM-HDI@TiO2 with better dispersibility and adsorption performance. The degradation of methylene blue under UV-light was performed to evaluate the photocatalytic performance of the resultant PSMM-HDI@TiO2. Compared with pristine TiO2, the PSMM-HDI@TiO2 exhibited not only higher degradation efficiency, but also facile separation and better reusability.

High-performance multifunctional porous iron Acetylacetonate/N, O-doped carbon nanospheres for electromagnetic wave absorption at 2–18 GHz and methyl orange absorption

Nowadays, multifunction is regarded as an advanced development direction of new-generation electromagnetic wave absorption (EMWA) materials to fulfill the ever-growing demands in complex environment and situation. Environmental pollution and electromagnetic pollution are all difficult problems for human beings all the time. Now, there is no multifunctional materials for collaborative treatment of environmental and electromagnetic pollution. Herein, We synthesized nanospheres with divinyl benzene (DVB) and N-[3-(dimethylamino)propyl]methacrylamide (DMAPMA), using a simple one-pot method. After calcination at 800 ℃ in N2, porous N, O-doped porous carbon materials were prepared. By regulating the mole ratio of DVB and DMAPMA, the ratio was 5:1 reached excellent EMWA property. Remarkably, the introduction of iron acetylacetonate into the reaction of DVB and DMAPMA was effective in enhancing the absorption bandwidth to 8.00 GHz at a 3.74 mm thickness, which depended on the synergistic effects from dielectric and magnetic losses. Simultaneously, the Fe-doped carbon materials had a methyl orange adsorption capacity. The adsorption isotherm conformed to the Freundlich model. After methyl orange absorption, the EMWA property did not greatly change. Thus, this research paves the way for the creation of multifunctional materials to solve environmental pollution and electromagnetic pollution together.

2-Methoxy-4-Vinylphenol as a Biobased Monomer Precursor for Thermoplastics and Thermoset Polymers.

To address the increasing demand for biobased materials, lignin-derived ferulic acid (FA) is a promising candidate. In this study, an FA-derived styrene-like monomer, referred to as 2-methoxy-4-vinylphenol (MVP), was used as the platform to prepare functional monomers for radical polymerizations. Hydrophobic biobased monomers derived from MVP were polymerized via solution and emulsion polymerization resulting in homo- and copolymers with a wide range of thermal properties, thus showcasing their potential in thermoplastic applications. Moreover, divinylbenzene (DVB)-like monomers were prepared from MVP by varying the aliphatic chain length between the MVP units. These biobased monomers were thermally crosslinked with thiol-bearing reagents to produce thermosets with different crosslinking densities in order to demonstrate their thermosetting applications. The results of this study expand the scope of MVP-derived monomers that can be used in free-radical polymerizations toward the preparation of new biobased and functional materials from lignin.

Identification and Quantitation of Nicotine Polacrilex in Nicotine Pouches and Other Oral Nicotine Delivery Products

SUMMARY Nicotine polacrilex (CAS-No. 96055-45-7) can be used as the source of nicotine in nicotine pouches and other oral nicotine delivery products such as lozenges, tablets, and gums. The compound is the salt of nicotine with Amberlite IRP64, a copolymer of methacrylic acid and divinylbenzene. Present study describes a unique procedure to identify the presence of the compound nicotine polacrilex in oral nicotine delivery products and to evaluate its level. In oral nicotine delivery products, nicotine polacrilex is used in a mixture with other ingredients such as microcrystalline cellulose (MCC), maltitol, sweeteners, flavors, salts (such as Na2CO3, NaHCO3), water, etc. These ingredients make the analysis of the compound nicotine polacrilex by spectroscopic techniques such as IR or Raman difficult. Also, since nicotine polacrilex is insoluble in common solvents, the analysis using solutions is not possible. The study is also attempting to detect if the product contains only nicotine polacrilex or if it has additional nicotine in a different form (e.g., nicotine or nicotine tartrate). The analysis uses pyrolysis-GC/MS (Py-GC/MS) and the detection and quantitation of nicotine polacrilex is based on measuring the pyrolysis products of divinylbenzene (DVB) moiety from the Amberlite IRP64. The detection was proven very reliable by this procedure, while the quantitation showed some variability caused by the typical variability in the pyrolysis process. [Contrib. Tob. Nicotine Res. 32 (2023) 43–49]

Solid phase extraction of ocean dissolved organic matter with PPL cartridges: efficiency and selectivity

Our current knowledge of the chemical composition of ocean dissolved organic matter (DOM) is limited, mainly because of its extreme molecular diversity, low concentration of individual compounds and the elevated ionic strength of ocean waters. As a result, many analytical methods require a previous extraction step. The efficiency and selectivity of the extraction method defines the representativeness of the extracted DOM fraction. Nowadays, the most widespread procedure for concentrating DOM is solid phase extraction (SPE) using styrene divinyl benzene polymer cartridges (PPL). Here, we investigate the effect of SPE-PPL on DOM elemental and optical properties to assess the efficiency and selectivity of this extraction method on water samples from the main intermediate and deep water masses of Arctic, Mediterranean and Antarctic origin present in the Cape Vert Frontal Zone (CVFZ, NW Africa). Furthermore, North and South Atlantic Central waters converge in this area and coastal DOM is injected by the giant upwelling filament of Cape Blanc. On one side, the colored fraction of DOM (CDOM) presented extraction efficiencies comparable to that of the bulk dissolved organic carbon (DOC), but decreased significantly with increasing wavelength, suggesting an affinity of PPL cartridges for low molecular weight organic compounds. While the protein-like fluorescent fraction of DOM (FDOM) was also extracted with the same efficiency than DOC, the extraction efficiency of the humic-like fraction was comparatively much higher. On the other side, dissolved organic nitrogen (DON) extraction efficiencies were about half that of DOC. These contrasting extraction efficiencies of the different DOM pools indicated that the extracts were enriched in N-poor, low molecular weight and recalcitrant DOM, therefore showing less variability than the corresponding bulk DOM. Furthermore, DOC, DON, CDOM and FDOM extracted were not homogeneous through the water column but displayed certain significant differences among water masses in both efficiency and selectivity.

Hierarchical Emulsion-Templated Monoliths (polyHIPEs) as Scaffolds for Covalent Immobilization of P. acidilactici.

The immobilized cell fermentation technique (IMCF) has gained immense popularity in recent years due to its capacity to enhance metabolic efficiency, cell stability, and product separation during fermentation. Porous carriers used as cell immobilization facilitate mass transfer and isolate the cells from an adverse external environment, thus accelerating cell growth and metabolism. However, creating a cell-immobilized porous carrier that guarantees both mechanical strength and cell stability remains challenging. Herein, templated by water-in-oil (w/o) high internal phase emulsions (HIPE), we established a tunable open-cell polymeric P(St-co-GMA) monolith as a scaffold for the efficient immobilization of Pediococcus acidilactici (P. acidilactici). The porous framework's mechanical property was substantially improved by incorporating the styrene monomer and cross-linker divinylbenzene (DVB) in the HIPE's external phase, while the epoxy groups on glycidyl methacrylate (GMA) supply anchoring sites for P. acidilactici, securing the immobilization to the inner wall surface of the void. For the fermentation of immobilized P. acidilactici, the polyHIPEs permit efficient mass transfer, which increases along with increased interconnectivity of the monolith, resulting in higher L-lactic acid yield compared to that of suspended cells with an increase of 17%. The relative L-lactic acid production is constantly maintained above 92.9% of their initial relative production after 10 cycles, exhibiting both its great cycling stability and the durability of the material structure. Furthermore, the procedure during recycle batch also simplifies downstream separation operations.

Computational approach to establish molecularly imprinted polymers interaction of functional monomer methacrylic acid and template norfloxacin

MIP is a potential method for fabricating polymeric materials with binding sites that have predetermined selectivity for a targeted analyte. The quality of the binding sites in MIP is directly influenced by monomer-template interaction strength. A computational approach is used to examine monomer-template interactions to obtain insight into the molecular level of imprinting polymer selectivity, regarding complex formation. In this work, five different monomers such as methyl methacrylic acid (MAA), methyl methacrylate (MMA), acrylonitrile (ACN), acrylamide (AA) and di-vinyl benzene (DVB) and their ratios with template have been screened. The geometry optimizations of the molecules were done using Amsterdam Modeling Suite (AMS) input program applying Amsterdam density function (ADF) module. The theoretical calculations were carried out exchange and correlation (XC) functional: RS: CAMY-B3LYP (Becke, 3-parameter, Lee–Yang–Parr) with basis set double zeta (DZ). The result showed the ratio of template to MAA was 1:3 for stable complex formation.

Bi-functional phosphonium poly(ionic liquid)s catalyzed CO2-promoted hydration of ethylene oxide

The highly selective production of monoethylene glycol (MEG) from ethylene oxide (EO) is desirable at low H2O/EO molar ratio, however, the development of an efficient heterogeneous catalyst for the reaction is a challenge. Herein, a series of bi-functional poly(ionic liquid)s (BF-PILs) were successfully synthesized by radical copolymerization of polymerizable phosphonium/ammonium ionic liquids, N-vinyl imidazole and cross-linker divinylbenzene (DVB). The structure and thermal stability of BF-PILs were characterized by NMR, FT-IR, elemental analysis and TGA. These BF-PILs could be swollen in the H2O and MEG mixture and the swelling ratio (Q) increased with the increase of the MEG mole fraction. Under swelling in the H2O and MEG mixture (1:1), BF-PILs presented an irregular channel structure with the diameter of 1–20 μm observed by the cryo-scanning electron microscope (cryo-SEM). BF-PILs were applied to catalyze the CO2-promoted hydration of EO at a low H2O/EO ratio of 1.5:1. The catalytic activities of phosphonium BF-PILs were superior to ammonium BF-PILs, and poly[(Ph)3VBPBr-VIm] with the greatest Q in the H2O and MEG mixture (1:1) gave highest yield (96.1%) and selectivity (97.3%) of MEG. The CO2-promoted hydration of EO involved the cycloaddition of EO with CO2 to produce ethylene carbonate (EC), and followed by the hydrolysis of EC to produce MEG. Kinetic experiments confirmed that phosphonium ionic liquid species mainly catalyzed CO2 cycloaddition and imidazole catalyzed hydrolysis of EC. Furthermore, poly[(Ph)3VBPBr-VIm] exhibited good generality and could be reused up to eight times without significant decrease of its initial activity.

Porous Polymers Based on 9,10-Bis(methacryloyloxymethyl)anthracene—Towards Synthesis and Characterization

Porous materials can be found in numerous essential applications. They are of particular interest when, in addition to their porosity, they have other advantageous properties such as thermal stability or chemical diversity. The main aim of this study was to synthesize the porous copolymers of 9,10-bis(methacryloyloxymethyl)anthracene (BMA) with three different co-monomers divinylbenzene (DVB), ethylene glycol dimethacrylate (EGDMA) and trimethylpropane trimethacrylate (TRIM). They were synthesized via suspension polymerization using chlorobenzene and toluene served as porogenic solvents. For the characterization of the synthesized copolymers ATR-FTIR spectroscopy, a low-temperature nitrogen adsorption-desorption method, thermogravimetry, scanning electron microscopy, inverse gas chromatography and size distribution analysis were successfully employed. It was found that depending on the used co-monomer and the type of porogen regular polymeric microspheres with a specific surface area in the range of 134-472 m2/g can be effectively synthesized. The presence of miscellaneous functional groups promotes divergent types of interactions Moreover, all of the copolymers show a good thermal stability up to 307 °C. What is important, thanks to application of anthracene derivatives as the functional monomer, the synthesized materials show fluorescence under UV radiation. The obtained microspheres can be used in various adsorption techniques as well as precursor for thermally resistant fluorescent sensors.