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Metal corrosion is a challenge for the world with heavy impacts on the economy. Study on the development of effectiveness anticorrosion additives is a promising strategery for the protection industry. This research focuses on the modification of hydrotalcite Mg-Al (HT) loading tannic acid (TA) with 3-(trimethoxy silyl) propyl methacrylate organo-silane (TMSPM) for applicating as an anti-corrosion additive for epoxy coating on the steel substrate. The suitable ratio of HT and modifiers was investigated and the suitable content of modified HT in epoxy matrix was found based on mechanical properties of the epoxy-based coating. The characteristics of modified HT were assessed through infrared (IR) spectroscopy, X-ray diffraction pattern (XRD), scanning electron microscopy (SEM), thermal gravimetry analysis (TGA), water contact angle (WCA), dynamic light scattering (DLS). Detailly, HT-TA3-S3 shows good stability in distilled water when HT/TA was modified with TMSPM which makes Zeta potential decreases significantly. Besides, SEM analysis presented HT-TA-S has a cylindrical shape about of 500 nm. Moreover, the crystallite size of HT/TA after being modified by TMSPM decreases sharply. All of these prove successfully synthesize HT loading TA with modified TMSPM. Water contact angle (WCA) decreases in case of loading TA and increases in case of modifying with TMSPM (WCA changed from HT (116.3°) to HT-TA (102.4°) and HT-TA-S (120.1°) which indicates the increased hydrophobicity of the sample. The obtained results showed HT/TA was modified successfully with TMSPM. The modification affected the size distribution and surface properties of HT nanoparticles while it did not impact on the crystal structure of HT. After incorporating modified HT/TA into the epoxy coating, the adhesion of coating to steel substrate was improved significantly. Consequently, the adhesion of epoxy/3 wt. % modified HT/TA coating was increased 3 times as compared to epoxy neat (from 0.76 MPa to 2.77 MPa). In addition, the relative hardness and gloss retention of epoxy/3 wt. % modified HT/TA coating reached the maximum values as compared to the others. Owing to salt spraying results, the epoxy/3 wt. % modified HT/TA exhibited an excellent anticorrosion ability for the steel substrate. All the above results show the potential of HT nanoparticles loading TA modified with TMSPM as anticorrosive additives for protective coatings on steel substrates.

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The organic modification of montmorillonite was successfully achieved using cetyltrimethyl ammonium bromide under facile conditions. The modified montmorillonite was subsequently used for the fabrication of montmorillonite-induced nanopore-rich cement paste (MNCP), and the shrinkage behavior and fundamental performance of MNCP were also investigated. The results indicate that alkali cations on a montmorillonite layer surface were exchanged by using CTAB under 80 °C, successfully achieving the organic modification of montmorillonite. As a pore-forming agent, the modified montmorillonite caused a reduction in shrinkage: the 28-day autogenous shrinkage at a design density of 400 kg/m3 and 800 kg/m3 was reduced to 2.05 mm/m and 0.24 mm/m, and the highest reduction percentages during the 28-day drying shrinkage were 68.1% and 62.2%, respectively. The enlarged interlamellar pores and hydrophobic effects caused by the organic modification of montmorillonite aided this process. Organic-modified montmorillonite had a minor influence on dry density and thermal conductivity and could contribute to an enhancement of strength in MNCP.

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This study assessed the methylene blue adsorption using natural and modified mussel shell powders in the aqueous solution. The mussel shell samples were processed in a NaClO solution then modified with sodium dodecyl sulfate and ethylenediaminetetraacetic acid. The characteristics of mussel shell samples before and after modification were demonstrated using infared spectroscopy, thermogravimetric analysis, scanning electron microscopy, nitrogen adsorption/desorption, energy dispersive X-ray, water contact angle, and dynamic light scattering methods. Some factors such as the pH of the medium, adsorption temperature, and adsorption time had a significant effect on the methylene blue adsorption of mussel shell samples. The adsorption isotherm models and kinetics of methylene blue adsorption by mussel shell samples were also studied. A quadratic regression equation was selected with experimental planning following the Box-Behnken model combined with Design Expert 11.1.0.1 software to optimize the methylene blue adsorption process by mussel shell samples. These results open a promising direction for using naturally derived materials to remove organic pollutants from contaminated water.

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Sodium-ion batteries (SIBs) are a possible candidate to create safe, sustainable, and cost-effective batteries. Solid sodium-ion conducting organically modified ionogel electrolytes are investigated. Silica-based ionogels typically consist of an ionic liquid electrolyte (ILE) confined within a silica matrix and possess high thermal stability, good ionic conductivity, safety, and good electrochemical stability. However, they readily deteriorate when stress is applied, decreasing the electrolyte's and battery's overall performance. The mechanical characteristics of silica can be improved using organic moieties, creating Ormosils®. Silica-based ionogels with phenyl-modified silanes improve the mechanical characteristics by a reduction of their Young's modulus (from 29 to 6 MPa). This is beneficial to the charge-transfer resistance, which decreases after implementing the electrolyte in half cells, demonstrating the improved interfacial contact. Most importantly, the phenyl groups change the interacting species at the silica interface. Cationic imidazolium species pi-stacked to the phenyl groups of the silica matrix, pushing the anions to the bulk of the ILE, which affects the ionic conductivity and electrochemical stability, and might affect the quality of the SEI in half cells. In essence, the work at hand can be used as a directory to improve mechanical characteristics and modify and control functional properties of ionogel electrolytes.

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This study investigates the montmorillonite (MMT) content, rotational viscosity, and colloidal index of sodium montmorillonite (Na-MMT) as a function of the sodium agent dosage, reaction time, reaction temperature, and stirring time. Na-MMT was modified using different octadecyl trimethyl ammonium chloride (OTAC) dosages under optimal sodification conditions. The organically modified MMT products were characterized via infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy. The results show that the Na-MMT with good properties (i.e., the maximum rotational viscosity and highest Na-MMT content with no decrease in the colloid index) was obtained at a 2.8% sodium carbonate dosage (measured based on the MMT mass), a temperature of 25 °C, and a reaction time of two hours. Upon organic modification of the optimized Na-MMT, OTAC entered the NA-MMT interlayer, and the contact angle was increased from 20.0° to 61.4°, the layer spacing was increased from 1.58 to 2.47 nm, and the thermal stability was conspicuously increased. Thus, MMT and Na-MMT were modified by the OTAC modifier.

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To achieve exceptional recyclable DC cable insulation material using thermoplastic polypropylene (PP), we have introduced the organic polar molecule styrene-maleic anhydride copolymer (SMA) into PP-based insulation materials following the principles of deep trap modification. PP, PP/SMA, PP/ethylene-octene copolymer (POE), and PP/POE/SMA insulating samples were prepared, and their meso-morphology, crystalline morphology, and molecular structure were comprehensively characterized. The results indicate that SMA can be uniformly dispersed in PP with minimal impact on the crystalline morphology of PP. The DC electrical properties of the materials were tested at temperatures of 30, 50, and 70 °C. The findings demonstrate that the introduction of SMA can improve the DC properties of the material in both PP and PP/POE. The thermal stimulated depolarization current results reveal that SMA can introduce deep traps into the material, thereby improving its DC properties, which is in agreement with the quantum chemical calculation results. Subsequently, a bipolar carrier transport model was employed for coaxial cables to simulate the space charge distribution in the insulation layer of the four sets of insulation samples as well as the actual cable in service. The results highlight that SMA can significantly suppress space charge in PP and PP/POE systems, and it exhibits excellent electric field distortion resistance. In summary, the results illustrate that SMA is expected to be used as an organic deep trap modifier in PP-based cable insulation materials.

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Nanofiltration (NF), highly prospective for drinking water treatment, faces a challenge in simultaneously removing emerging contaminants while maintaining mineral salts, particularly divalent cations. To overcome this challenge, NF membranes possessing small pores concomitant with highly negatively charged surfaces were synthesized via a two-step fabrication strategy. The key is to generate a polyamide active layer having a loose and carboxyl group-abundant segment on top and a dense barrier segment underneath. This was achieved by restrained interfacial polymerization between trimesoyl chloride and partly protonated piperazine to form a highly depth-heterogeneous polyamide network, followed by second amidation in an organic environment to remove untethered polyamide fragments and associate malonyl chlorides with reserved amine groups to introduce more negative charges. Most importantly, on first-principle engineering the spatial architecture of the polyamide layer, amplifying asymmetric charge distribution was paired with the thinning of the vertical structure. The optimized membrane exhibits high salt/organic rejection selectivity and water permeance superior to most NF membranes reported previously. The rejections of eight emerging contaminants were in the range of 66.0-94.4%, much higher than the MgCl2 rejection of 41.1%. This new fabrication strategy, suitable for various diacyl chlorides, along with the new membranes so produced, offers a novel option for NF in potable water systems.

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In this study, SBA-15 was functionalized by organic groups (-CH3, -C4H9, -C8H17, -CH2CH2NH2, -C6H5, et al.), and then Lecitase® Ultra (LU) was immobilized onto the modified SBA-15 for soybean oil degumming. The hydrolysis activity, degumming performance, reusability in degumming, and the composition of phospholipids in the gum, of the immobilized LU samples, were carefully studied. Hydrolysis activities over 1800 U/g were obtained from all the immobilized LU samples. The highest activity of up to 4554.17 U/g was observed from the 3-ureidopropyl group-modified SBA-15-supported LU. Most of the immobilized LU samples removed the phospholipids effectively from crude soybean oil (initial phosphorous content 314.23 mg/kg), with a residual phosphorus content of less than 10 mg/kg. The reusability of the immobilized LU samples in the degumming process was evaluated. No loss of activity was observed from the methyl and N-(2-aminoethyl)-3-aminopropyl group-modified SBA-15-supported LU samples after five cycles of reuse. In addition, 3-aminopropyl and 3-glycidyloxypropyl group-modified SBA-15-supported LU samples retained over 90% of their initial activity; N-phenylaminomethyl and 1-isocyanatopropane group-functionalized SBA-15-supported LU samples retained approximately 80% of their initial activity. The phospholipids in the gum were analyzed. The n-octadecyl and N-(2-aminoethyl)-3-aminopropyl group-functionalized SBA-15-supported LU samples were selective for lysophosphatidylethanolamine (LPE) preparation, and LPE percentages up to 37.14 and 38.80% were obtained, respectively. The N-phenylaminomethyl group-modified SBA-15-supported LU showed selectivity toward lysophosphatidylcholine (LPC) production, with an LPC percentage of up to 38.5%.

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In order to realize the high value-added resource utilization of solid waste and reduce the cost of rubber manufacturing, iron ore tailings (IOTs) were used as raw material to prepare a reinforcing filler of rubber through ultrafine grinding and surface organic modification techniques. We studied the effects of ball mill grinding conditions on the particle size and distribution of grinded iron ore tailings (G-IOTs). The effects of bis-(triethoxy-silyl-propyl)-tetrasulfide (Si69)-modified G-IOT (Si69-G-IOT) loading levels on the cure characteristics, static mechanical and dynamic mechanical properties of the styrene butadiene rubber (SBR) composites were also explored in this paper. The grinding and modification mechanism of IOTs and the combination of filler and SBR matrix were explored by grinding simulation of population balance model, X-ray diffraction analysis, Fourier transform infrared spectroscopy and scanning electron microscopy. The results showed that when grinding IOTs at 2000 r/min for 150 min, the particle size distribution of the resulting G-IOTs was the narrowest, with a D90 value of 4.42 µm. The tensile strength and elongation at break of SBR filled with 120 phr Si69-G-IOT were 14.97 MPa and 596.36%, respectively.

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SBS-modified bitumen (SMB) is susceptible to aging, which seriously influences its service performance and life. In order to strengthen the anti-aging ability of SMB, triethoxyvinylsilane was designed to organically modify layered double hydroxides (LDHs) and was applied to modify SMB. The dispersibility and storage stability of LDHs in SMB were markedly enhanced after triethoxyvinylsilane organic modification, and the compatibility and storage stability of SBS in bitumen were simultaneously enhanced. Compared with SMB, the introduction of LDHs and organic LDHs (OLDHs) could ameliorate the high-temperature properties of SMB, and the thermostability of SBS in bitumen at a high temperature was also distinctly improved, especially OLDHs. After aging, due to the oxidation of molecular bitumen and the degradation of molecular SBS, SMB became hardened and brittle, and the rheological properties were significantly deteriorated, which had serious impacts on the performance of SMB. LDHs can mitigate the detriment of aging to bitumen and SBS, and the deterioration of the rheological properties of SMB is obviously alleviated. As a result of the better dispersibility and storage stability, OLDHs exerted superior reinforcement of the anti-aging ability of SMB.

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Nanoarchitecture of hybrids materials based on clay minerals as nano building blocks for the environmental remediation is summarized with the emphasis on the utilization of layered clay minerals, especially smectite group of clay minerals, as nano building blocks for designing functional nanostructures for the adsorption of molecular contaminants from the environments. Smectites are well-known adsorbents of cationic contaminants, while surface modification of smectites with organoammonium ions has given hydrophobic and microporous characters to uptake nonionic organic contaminants from environments. Not only on the designed interactions between adsorbent-adsorbate for efficient and higher capacity adsorption, the states of the adsorbed nonionic organic compounds have been altered and varied by the modification of smectites as shown by the controlled release and specific catalytic reactions. The organically modified clays are classified from the nanoarchitecture, and the functions derived from the nanoarchitectures are discussed based on the structure-property relationship.

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BACKGROUND: In this study, SBA-15 was functionalized by silane coupling reagents, then lipase from Thermomyces lanuginosus (TLL) was immobilized onto the parent and the organically modified SBA-15 for diacylglycerol (DAG) production through glycerolysis. RESULTS: Diacylglycerol content of 54.77 ± 0.63%, and triacylglycerol (TAG) conversion of 77.75 ± 1.24%, were obtained from the parent SBA-15 supported TLL-mediated glycerolysis reaction in a solvent-free system. However, poor performance was unexpectedly observed when co-solvents were introduced into the reaction system. After organic modification, the functionalized SBA-15 supported TLL samples all exhibited reasonable performance, producing DAG content over 40 wt% and TAG conversion over 70 wt%. Higher DAG content, up to 59.19 ± 1.10%, was observed from the phenyl group-modified SBA-15 supported TLL. The operational stability of the immobilized TLL samples in glycerolysis was also improved after organic functionalization. The phenyl group-modified SBA-15 supported TLL showed good reusability in the present glycerolysis reaction, and 95.21 ± 4.87% of the initial glycerolysis activity remained after five cycles of reuse. CONCLUSION: The organic modification of SBA-15 improved the catalytic performance of its supported TLL in glycerolysis, in terms of TAG conversion, DAG content, and reusability. © 2019 Society of Chemical Industry.

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Arsenic (As) poses a tremendous threat to human health due to exposure through arsenic-contaminated drinking water and/or food. We aimed to develop organically modified clay adsorbents for the removal of As from aqueous solution. We modified a smectite sample using three organic agents, namely hexadecyl trimethylammonium (HDTMA), chitosan and citric acid, and characterized the products using X-ray diffraction, infrared spectroscopy, and scanning electron microscopy techniques. The characterization techniques suggested successful organic modifications of the smectite sample. The surfactant-modified smectite was the most efficient (66.9%) As removing adsorbent with a maximum adsorption capacity of 473.2 µg g-1. Kinetic study showed that the adsorbents reached As adsorption equilibrium within 3 h, and the data fitted reasonably well to power function and simple Elovich equations (R2 > 0.89). The adsorption data were explained well by the Freundlich and Sips isothermal models. The surfactant-modified and chitosan-grafted organoclays adsorbed As by electrostatic attraction and anion exchange, whereas the citric acid activated smectite followed ligand exchange and simple anion exchange mechanisms. This study thus demonstrated the potential of surfactant-modified clays in removing As from contaminated waters.

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Organically modified clays can be used as nanofillers in polymer-clay nanocomposites to create bio-based packaging with improved strength and barrier properties. The impact of organic modification on the physico-chemical properties and toxicity of clays has yet to be fully investigated but is essential to ensure their safe use. Two organoclays, named N116_HDTA and N116_TMSA, were prepared using a commercially available sodium bentonite clay and the organic modifiers hexadecyl trimethyl ammonium bromide (HDTA) and octadecyl trimethyl ammonium chloride (TMSA). An in vitro hazard assessment was performed using HaCaT skin cells, C3A liver cells, and J774.1 macrophage-like cells. Organic modification with HDTA and TMSA increased the hazard potential of the organoclays in all cell models, as evidenced by the higher levels of cytotoxicity measured. N116_TMSA caused the greatest loss in viability with IC50 values of 3.2, 3.6 and 6.1 µg/cm2 calculated using J774.1, HaCaT and C3A cell lines, respectively. Cytotoxic effects were dictated by the amount of free or displaced organic modifier present in the exposure suspensions. The parent bentonite clay also caused distinct cytotoxic effects in J774.1 macrophage-like cells with associated TNF-α release. Such information on the hazard profile of organoclays, can feed into risk assessments for these materials.

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In this study, organic structures were introduced onto copper cathodes to induce changes in their electrocatalytic CO2 reduction activity. Poorly soluble organic polymers were distributed onto the copper surface as a thin layer by polymerizing monomeric precursors via a copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) activated by anodization of the copper substrate. The resulting structure possesses copper surface atoms that are available to participate in the CO2 reduction reaction-comparable to close-contact organic structures-and stabilize the adsorption of organic layers through the CO2 reduction process. The CO2 reduction performance of the on-surface modified copper cathode exhibited improved CO2 reduction over H2 evolution compared with traditional cast modification systems. Preventing organic moieties from forming densely packed assemblies on the metal surface appears to be important to promote the CO2 reduction process on the copper atoms. The suppression of H2 evolution, a high methane/ethylene ratio, and the influence of stirring demonstrate that the improved CO2 reduction activity is not only a result of the copper atom reorganization accompanied by repeating anodization for modification; the organic layer also apparently plays an important role in proton transfer and CO2 accumulation onto the copper surface.

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To achieve an enhanced and selective adsorption of steroid estrogens, the n-propyl functionalization was applied to the mesoporous silica material (MCM-41) according to the physico-chemical property analysis of steroid estrogens. Adsorption behaviour and water chemistry effects were evaluated with the most concerned steroid estrogens: estrone (E1), 17ß-estradiol (E2) and 17α-ethinyl estradiol (EE2) based on the materials characterization. The results showed the uptakes of E1, E2, and EE2 onto the modified MCM-41 were enhanced and accelerated by the n-propyl functionalization, which was positively correlated with the hydrophobicity of the synthesized materials. Kinetic data fitted the pseudo-second-order model well. Based on the Langmuir model, the maximum adsorption capacities of the n-propyl modified MCM-41 were up to 119.87, 88.38, and 86.91 mg g-1 for EE2, E1, and E2, respectively. Importantly, both acid and neutral solutions were beneficial to estrogen removal, but ionic strength and humic acid did not affect the estrogen adsorption. The above results suggested that the n-propyl functionalized MCM-41 would be a promising adsorbent for the rapid and efficient removal of estrogens with the selectivity from natural organic matter like humic acid. Mechanism analysis showed the key role of hydrophobic interaction, and it also confirmed the contribution of the carbonylic lone pair electrons of E1, which helped the formation of stronger hydrogen bonds with silicon hydroxyls and enhanced the dipole-dipole interaction between E1 and the synthesized materials.

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A novel phosphonate assisted fabrication dendritic fibrous nanosilica (DFNS)-based adsorbing material was successfully synthesis via organic modification with 3-aminopropyltriethoxysilane (KH550), epichlorohydrin (ECH) and phytic acid (PA) on the grounds of hard-soft-acid-base theory, in which organic phosphorous can be applied for efficient chelating uranium(VI) (U(VI)). The adsorption properties can be evaluated by setting a series parameters (pH, adsorbent dose, contact time, initial U(VI) concentration). It is clear that uranium as a "hard" lewis acid can easily form chelating bond with "hard" donor-ligands so that as-papered PA-DFNS has an excellent adsorption capacity (qm = 1106 mg g-1, 298.15 K), which exhibits a 163% increment compared with that of original DNFS under the same condition. In the meantime, the adsorption equilibrium time of PA-DNFS (t = 60 min) was shortened by 33% compared with that of pristine DNFS. Besides, the PA-DFNS exhibited good removal efficiency and stability under the 0.1 M HNO3 after 6 cycles, extending the application of PA-DFNS in the field of adsorption.

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In this study, SBA-15 was modified by a series of silane coupling reagents and later used to immobilize Candida antartica lipase B (CALB). The enzymatic properties of the immobilized CALB samples were studied. In addition, the catalytic performance in glycerolysis of soybean oil for diacylglycerols (DAG) production was also investigated. The highest enzymatic activity up to 6100.00 ±â€¯246.41 U/g was observed from the propyl methacrylate group modified SBA-15 supported CALB. No loss of activity was observed from the propyl methacrylate group modified SBA-15 supported CALB, but a higher-than-initial activity was notably found from 3-aminopropyl group and n-octyl group modified SBA-15 supported CALB after a 4-h incubation in air at 70 °C. 1-isocyanatopropane group modified SBA-15 supported CALB exhibited selectivity for DAG production. DAG content up to 61.90 ±â€¯2.38 wt% and a DAG/MAG ratio at 3.11 ±â€¯0.08 was obtained after a 24-h reaction at 60 °C in a solvent-free system.

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γ-(2,3-Epoxypropoxy)propyltrimethoxy silane surface modified layered double hydroxides (KH560-LDHs) were prepared and used to improve the ultraviolet ageing resistance of asphalt. The results of X-ray photoelectron spectrometry (XPS) indicated that KH560 has been successfully grafted onto the surface of LDHs. The agglomeration of LDHs particles notably reduced after KH560 surface modification according to scanning electron microscopy (SEM), which implied that the KH560 surface modification was helpful to promote the dispersibility of LDHs in asphalt. Then, the influence of KH560-LDHs and LDHs on the physical and rheological properties of asphalt before and after UV ageing was thoroughly investigated. The storage stability test showed that the difference in softening point (ΔS) of LDHs modified asphalt decreased from 0.6 °C to 0.2 °C at an LDHs content of 1% after KH560 surface modification, and the tendency became more pronounced with the increase of LDH content, indicating that KH560 surface modification could improve the stability of LDHs in asphalt. After UV ageing, the viscous modulus (G'') of asphalt significantly reduced, and correspondingly, the elastic modulus (G') and rutting factor (G*/sin δ) rapidly increased. Moreover, the asphaltene increased and the amount of "bee-like" structures of the asphalt decreased. Compared with LDHs, KH560-LDHs obviously restrained performance deterioration of the asphalt, and helped to relieve the variation of the chemical compositions and morphology of asphalt, which suggested that the improvement of KH560-LDHs on UV ageing resistance of asphalt was superior to LDHs.