Nanomaterials (Basel)
November 2023
In order to enhance the mechanical properties of UV-curable epoxy acrylate (EA)-based coatings, 3-(trimethoxysilyl)propyl methacrylate modified aramid nanofibers (T-ANFs) were synthesized and used as nanofillers to prepare EA/T-ANF nanocomposite films. The morphology of T-ANFs was characterized by transmission electron microscopy. The chemical structure of T-ANFs was analyzed via infrared spectroscopy, confirming successful grafting of methyl methacryloyloxy groups onto the surface of aramid nanofibers (ANFs).
View Article and Find Full Text PDFConductive aramid (PPTA) fibers are highly needed for making flexible conductive materials, antistatic materials, and electromagnetic shielding materials. In this work, silver-plated conductive PPTA fibers with high conductivity and excellent mechanical properties were prepared by the electroless plating of PPTA fibers modified with crosslinked hyperbranched polyamide-amine (HPAMAM). The crosslinked HPAMAM creates a stable interface between the PPTA fibers and the silver plating.
View Article and Find Full Text PDFDendrimers as commonly used metal ions adsorption materials have the advantages of good adsorption performance and high reuse rate, but the high cost limits its extensive use. Compared with dendrimers, hyperbranched dendrimers have similar physical and chemical properties and are more economical. Therefore, hyperbranched dendrimers are more suitable for industrial large-scale adsorption.
View Article and Find Full Text PDFAramid nanofibers (ANFs) represent the most promising nanoscale building blocks for high-performance nanocomposites. But their applications are mostly limited to those polymers containing -OH or -NH groups that can interact with ANFs through hydrogen bonding or others. In this paper, allyl and benzyl modified ANFs were successfully fabricated using a metallization method followed by functionalization with allyl and benzyl bromide.
View Article and Find Full Text PDFAramid nanofibers (ANFs) are a novel type of promising nanoscale building blocks for high-performance nanocomposites. Conventionally, ANFs are used to composite with polymers containing polar groups such as -OH and -NH since those polymers can interact with the amide groups in ANFs through polar-polar interaction such as hydrogen bonding. In this study, ANFs were derivatized with non-polar alkyl groups including ethyl, octyl and dodecyl groups and used as a performance-enhancing additive to polyvinyl chloride (PVC) with weak polarity.
View Article and Find Full Text PDFTo further increase the quantity and density of functional groups on adsorbent, terminal triethylenetetramine hyperbranched dendrimer-like polymer modified silica-gel (SG-TETA and SG-TETA2) was synthesized. The hyperbranched dendrimer-like polymer was successfully introduced onto silica gel and new cavities were formed, which was demonstrated by FTIR, SEM, and BET. The highest adsorption capacities of SG-TETA and SG-TETA2 obtained from Langmuir model toward Au(III) were 2.
View Article and Find Full Text PDFA double reagents simultaneous functionalization (DRSF) was used to prepare porous polysilsesquioxane with NH and SH bifunctional groups (PAMPSQ) coated poly(-phenylenetherephthal amide) (PPTA) fibers adsorbents (PPTA-AM), via condensations with aminopropyltriethoxysilane (APTES) and mercaptopropyltriethoxysilane (MPTES). The PAMPSQ coated on the PPTA surface was in the form of nanoparticles and its morphology varied with the proportion of the reactants. The PAMPSQ exhibited loose open meso- or macroporous features.
View Article and Find Full Text PDFA series of bridged polysilsesquioxane (BPS) materials was synthesized by the sol-gel method from 3-chloropropyl trimethoxysilane, diethylenetriamine (DETA) or ethylenediamine. Tetraethyl orthosilicate (TEOS) and/or one of the two templates, hexadecyl trimethyl ammonium bromide (CTAB) or P123, were used in the co-condensation process to construct some of the porous adsorbents. The adsorption of Au(III) was the highest for samples without TEOS, especially for the DETA series with CTAB template.
View Article and Find Full Text PDFA series of silica gel supported amino-terminated PAMAM dendrimers (SG-G1.0 - SG-G3.0) were used for the removal of Cd(II) and Fe(III) from dimethylsulfoxide (DMSO).
View Article and Find Full Text PDFInitially, porous acrylonitrile/itaconic acid copolymers (AN/IA) were prepared by suspended emulsion polymerization. Successively, the cyano groups in AN/IA copolymers were converted to amidoxime (AO) groups by the reaction with hydroxylamine hydrochloride. The structures of the AN/IA and amidoximated AN/IA (AO AN/IA) were characterized by infrared spectroscopy, scanning electron microscopy, and porous structural analysis.
View Article and Find Full Text PDFBiodiesel production has become an intense research area because of rapidly depleting energy reserves and increasing petroleum prices together with environmental concerns. This paper focused on the optimization of the catalytic performance in the esterification reaction of oleic acid for biodiesel production over the bifunctional catalyst organotriphosphonic acid-functionalized ferric alginate ATMP-FA. The reaction parameters including catalyst amount, ethanol to oleic acid molar ratio and reaction temperature have been optimized by response surface methodology (RSM) using the Box-Behnken model.
View Article and Find Full Text PDFFive N-methyl-N-R-N,N-bis(2-hydroxyethyl) ammonium bromides (R = -benzyl (chloride, BNQAS), -dodecyl (C12QAS), -tetradecyl (C14QAS), -hexadecyl (C16QAS), -octadecyl (C18QAS)) were prepared based on N-methyldiethanolamine (MDEA) and halohydrocarbon. Five QAS were characterized by FTIR, NMR, and MS. BNQAS, C12QAS, C14QAS, and C16QAS were confirmed by X-ray single-crystal diffraction.
View Article and Find Full Text PDFA series of silica gel supported salicylaldehyde modified PAMAM dendrimers (SiO2-G0-SA ∼ SiO2-G2.0-SA) were synthesized and their structures were characterized by FTIR, XRD, SEM, TGA, and porous structure analysis. The feasibility of these adsorbents for the removal of Hg(II) from aqueous solution was first described and the adsorption mechanism was proposed.
View Article and Find Full Text PDFToxic heavy metals in beverages can seriously harm human health. In the present work, a facile and eco-friendly biosynthesis of mesoporous cadmium phosphate (MPCP), using bovine serum albumin (BSA), has been successfully developed. BSAs were used to regulate the nucleation and growth of cadmium phosphate; MPCP has been used for lead ions removal from juice beverage solution and it has very excellent adsorption property capacity for Pb(II).
View Article and Find Full Text PDFNovel biosorbent materials (RH-2 and RH-3) obtained from agricultural waste materials rice husks (RH-1) were successfully developed through fast and facile esterification reactions with hydroxylethylidenediphosphonic acid and nitrilotrimethylenetriphosphonic acid, respectively. The present paper reported the feasibility of using RH-1, RH-2 and RH-3 for removal of heavy metals from simulated wastewater, the results revealed that the adsorption property of functionalized rice husks with organotriphosphonic acid RH-3 for Au(III) was very excellent, especially for gold ions. The combined effect of initial solution pH, RH-3 dosage and initial Au(III) concentration was investigated using response surface methodology (RSM), the results showed that initial Au(III) concentration exerted stronger influence on Au(III) uptake than initial pH and biomass dosage.
View Article and Find Full Text PDFAn efficient bifunctional catalyst lipase/organophosphonic acid-functionalized silica (SG-T-P-LS) has been successfully developed, and biodiesel production of fatty acid ethyl ester (FAEE) from free fatty acid (FFA) oleic acid with short-chain alcohol ethanol catalyzed by SG-T-P-LS was investigated. The process optimization using response surface methodology (RSM) was performed and the interactions between the operational variables were elucidated, and it was found that the molar ratio of alcohol to acid was the most significant factor. The optimum values for maximum conversion ratio can be obtained by using a Box-Behnken center-united design, and the conversion ratio could reach 89.
View Article and Find Full Text PDFThe adsorption properties of silica-gel supported hyperbranched polyamidoamine dendrimers (SiO(2)-G0-SiO(2)-G4.0) have been investigated by batch method. The effect of pH of the solution, contact time, initial Pb(II) ion concentration, temperature and coexisting metal ions have been demonstrated.
View Article and Find Full Text PDFNovel biomass-based adsorbents organophosphonic acid functionalized spent buckwheat hulls (OPA-BH) with 60 mesh were successfully employed to adsorb Au(III) ions from simulated wastewater. The adsorption kinetics and isotherms both in unary ion system and in ternary ions system were investigated, and the applicability of the Langmuir, Freundlich and extended Langmuir isotherm models has been tested for the equilibrium. The process optimization was also conducted by using response surface methodology (RSM), and the maximum adsorption capacities reached 2.
View Article and Find Full Text PDFThe adsorption kinetics and adsorption isotherms of buckwheat hulls in the region of Jiaodong, China (BHJC) for Hg(II) were investigated. Results revealed that the adsorption kinetics of BHJC for Hg(II) were well described by a pseudo second-order reaction model, and the adsorption thermodynamic parameters ΔG, ΔH and ΔS were -5.83 kJ mol(-1)(35°C), 73.
View Article and Find Full Text PDFNovel biosorbent materials obtained from agricultural residues buckwheat hulls (BH) were successfully developed through functionalization with 1-hydroxylethylidenediphosphonic acid (HEDP), and they were characterized. This paper reports the feasibility of using HEDP-BH for removal of heavy metals from stimulated wastewater, the experimental results revealed that the adsorption property of functionalized buckwheat hulls with 120 mesh 120-HEDP-BH for Au(III) was very excellent, and the monolayer maximum adsorption capacity for Au(III) calculated from the Langmuir isotherm models was up to 450.45 mg/g at 35 °C.
View Article and Find Full Text PDFMater Sci Eng C Mater Biol Appl
August 2012
Yb-based catalyst was used for the first time for atom transfer radical polymerization using activators generated by electron transfer (AGET ATRP) of acrylonitrile (AN) with 2-bromopropionitrile (BPN) as initiator, 2, 2'-bipyridine (bipy) as ligand, and tisn(II) bis(2-ethylhexanoate) (Sn(EH)2) as reducing agent in the presence of air. With respect to AGET ATRP of AN catalyzed by CuBr2, an evident increase of polymer tacticity was observed for AGET ATRP of AN. The increase of syndiotacticity became more and more pronounced than the increase of isotacticity of polyacrylonitrile (PAN) along with YbBr3 content.
View Article and Find Full Text PDFEsterification of oleic acid with ethanol catalyzed by organophosphonic acid-functionalized silica SG-T-P was optimized using response surface methodology (RSM). The interactive effect of catalyst to FFA weight ratio and molar ratio of alcohol to acid were more significant than that of reaction temperature. The optimum values for maximum conversion ratio obtained by a Box-Behnken center-united design reached 77.
View Article and Find Full Text PDFA novel method of surface modification was developed via iron (III)-mediated atom transfer radical polymerization, with activators regenerated by electron transfer (ARGET ATRP) on the surfaces of polystyrene resin-supported N-chlorosulfonamide groups. The well-defined polyacrylonitrile (PAN) was grafted onto the surfaces of the polystyrene (PS). The graft reaction exhibited first-order kinetics with respect to the polymerization time in the low-monomer-conversion stage.
View Article and Find Full Text PDFPorous acrylonitrile (AN)/methyl acrylate (MA) copolymer beads were prepared by suspended emulsion polymerization. The cyano groups in AN/MA copolymer beads were converted to amidoxime (AO) groups by reaction with hydroxylamine hydrochloride (NH(2)OH.HCl) to remove metal ions in aqueous solution.
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