Resin mesoporous

Cuan J, Yan B (2013) Cool-white light emitting hybrid materials of resin-mesoporous silica composite matrix encapsulating europium polyoxometalates through ionic liquid linker. RSC Adv 3 20077-20084... 

Silicon, the second most abundant element in the earths crust after oxygen, is widely used in the manufacture of siloxane-based materials. Such materials find application as semiconductors, glasses, ceramics, plastics, elastomers, resins, mesoporous molecular sieves, optical fibers, coatings. 

Iron oxide nanocomposites have been prepared by hydrolysis of iron salts in sulfonated polystyrene resins, mesoporous sulfonated styrene-divinylbenzene copolymer, acrylonitrile-methyl methaciylate-divinylbenzene copolymer, cross-linked high amylose starch, polyimides, polyvinylpyridine, polypyrrole,eellulosies. Nanocomposites of metals (Cr, Mo, W, Fe, Co, Ni) with a variable particle size (2-10 mn), have been prepared from solutions of metal preeursors in a molten polymer (polyethylene, polypropylene, polytetra-fluoroethylene, polyamide, polyaiylate, polycarbonate, polystyrene, polyethers, polyphenyleneoxide, siloxane). There are also many examples of in-situ precipitation of iron oxides in aqueous solution of polymers, such as dextran, PVA, polyethylene glycol, etc. In this case, size dispersion and aggregation are frequent, but they can be minimized by using reverse micelles. ... 

The hydroamination of alkenes has been performed in the presence of heterogeneous acidic catalysts such as zeolites, amorphous aluminosilicates, phosphates, mesoporous oxides, pillared interlayered clays (PILCs), amorphous oxides, acid-treated sheet silicates or NafioN-H resins. They can be used either under batch conditions or in continuous operation at high temperature (above 200°C) under high pressure (above 100 bar). 

The ruthenium catalysts have also been attached to various solid supports, including nolyethy-leneglycol (PEG), " mesoporous molecular sieves, " and Merrifield s peptide resin. " ... 

A variety of SCS and PCP Pd (II) pincer complexes were prepared and immobilized on polymer or silica supports. (Figure 2 shows supported PCP complexes on poly(norbornene) and silica). Insoluble supports such as mesoporous silica and Merrifield resins along with soluble supports such as poly(norbornene) allowed for generalization of our observations, as all immobilized catalysts behaved similarly. The application of poisoning tests, kinetics studies, filtration tests, and... 

CW/templated resin (TPR), 50 pm, is used for analysis of surfactants by HPLC. The templated resin in CW/TPR is a hollow, spherical DVB formed by coating DVB over a silica template. When the silica is dissolved, the hollow, spherical DVB particle formed has no micro- or mesopores [135],... 

Removal of heavy-metal ions has been a major focus in environmental remediation and cleanup. Various materials, such as activated charcoal, clays, sihca gels, and ion-exchange resins have been used as adsorbents. Functionahzed mesoporous sihcas have recently proved to be a promising or even better alternative. Mercier etal. prepared a... 

Mesoporous melamine-formaldehyde and phenolic-formaldehyde resins were synthesized in the process of polymerization in the presence of fumed silica as an inorganic template. The surface and structural characteristics of the obtained sorbents were investigated using XPS technique and sorption from gas phase. The parameters characterizing porous structure of the synthesized resins in a dry state were determined from nitrogen adsorption/desorption isotherms. The sorption processes of benzene and water vapor accompanied by simultaneous swelling of both polymers were also studied. 

Data of low-temperature nitrogen adsorption were used to evaluate the parameters characterizing the pore structure of the obtained polymeric materials in dry state. The BET specific surface area, Sbet, and the total pore volume, V, were estimated by applying the standard methods Sbet from the linear BET plots and F/ from adsorption at relative pressure p/po=0.975) [7]. The mesopore structure was characterized by the distribution function of mesopore volume calculated by the Barret-Joyner-Halenda (BJH) method [27]. In Table 2 the values of these parameters are given for both synthesized polymers. The melamine-formaldehyde resin MEA has a more developed pore structure (5 B 7=220mVg, F,=0.45cm /g) and narrower mesopores (D=7.3nm) in comparison to the phenolic-formaldehyde polymer PHD. 

Results of adsorption experiments are presented in Table 2. In solution, TNF-a, a polypeptide with MW 17 kD, exists as a trimer with MW 51 kD. The monomeric units are kept together due to the hydrophobic interaction. From the experimental data it is clear that large mesopores play a relatively minor role in adsorption of TNF-a, as both MN resins adsorb it rather efficiently. Isoelectric point of TNFa is similar to that of serum albumin (pi between 4.8 and 5.6) [11], It has been shown that TNFa can be removed from biological media using non-polar cross-linked polystyrene adsorbents of the Amberlite type (XAD-2, XAD-4 and XAD-6) [12], This observation confirms that hydrophobic interactions play an important role in the adsorption of TNFa at neutral pH. Our data support this conclusion. 

The principle of the carbon synthesis is shown in Fig. 1. Suitable carbon sources such as sucrose, furfuryl alcohol, phenol-resin monomers and acetylene gas are converted to carbon frameworks inside mesoporous silica template by pyrolysis. An effective method for the restriction of carbonization to inside the template is to incorporate a suitable catalyst such as Al, Sn and Fe onto the silica pore walls prior to the use as template. The template after the carbonization is removed using ethanol-water solution of HF or NaOH. 

An ion-exchange resin was used as a precursor of the mesoporous activated carbon to prepare a starting material in which some amount of Fe ions were introduced with high dispersion. Commercially supplied acrylic type cation exchange resin with carboxyl... 

The introduced Fe contributes to increase the specific surface area and mesopore of the activated carbon as shown in Fig.3. The Fe ions migrate in the resin to form nanoparticles of Fe compounds during the heat-treatment. Along with the formation of the particles of Fe compounds, the mesopore of the activated carbon may also be produced at the sites where the Fe compounds migrated. In the case of a-Fe, the a-Fe particles may act as a catalyst for gasification of the carbons around the particles in H2 atmosphere at above... 

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