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Herein, the synthesis of functionalized polymer microspheres core-shell structure is successfully fabricated by a process involving three steps: (1) preparation of superparamagnetic Fe3O4 nanoparticles through a co-precipitation method, (2) Fe3O4 nanoparticles were functionalized using polypyrrole (PPy), a natural amino acid, to graft Hg(II) and azo dyes onto the surface of the nanocomposite, and (3) immobilization of meso-tetrakis (4-carboxyphenyl) porphyrin based on Fe3O4/PPy core-shell by a facile route. To recluse investigation of the ratio effect of core and shell amounts, the adsorbent was prepared with two different percentages: 2.53 and 33. In this work, some critical factors on the efficiency of adsorbent have been studied, including concentration and time. Structural and morphological changes induced by modification were confirmed by X-ray diffraction, Fourier transforms infrared, scanning electron microscopy, and energy-dispersive X-ray spectroscopy analysis. UV-visible (UV-vis) spectra illustrate the elimination percentages of methylene blue (MB) and methyl orange (MO). Inductively coupled plasma analysis was used to investigate the removal of Hg(II) ions. The results illustrated that the adsorbent shows efficiency up to 100%. Furthermore, UV-vis spectroscopy was used to show that the prepared nanocomposite removes MB and MO dyes with a yield of 100% and 95%, respectively. The porous structure was also investigated by Brunauer–Emmett–Teller analysis, and a type VI isotherm was obtained. The magnetic nanocomposite is featured with superparamagnetism, excellent reusability, and a high anti-interfering ability to remove Hg(II) toxic ions and organic pollutants such as MB and MO in an aqueous medium at room temperature. [ABSTRACT FROM AUTHOR]

Highlights: [•] Novel reactive methyl cellulose-derived polymers obtained by NCO functionalization. [•] Preparation of oleogels from NCO-functionalized methyl cellulose and castor oil. [•] These oleogels can be proposed as biobased alternatives to lubricating greases. [•] Oleogels rheological response depends on methyl cellulose functionalization degree. [ABSTRACT FROM AUTHOR]

Abstract: A novel chelating polymeric material was synthesized by chemical anchoring of N,N′-dimethyl-N,N′-dibutyl malonamide (DMDBMA) with chloromethylated polystyrene-divinyl benzene polymer. The polymeric material thus prepared was characterized by 13C NMR, FT-IR spectroscopy and CHN elemental analysis. The fabricated polymeric material exhibited superior binding for hexa-valent and tetra-valent metal ions such as U(VI) and Th(IV). Various physico-chemical properties of the functionalized polymer like phase adsorption kinetics, metal sorption mechanism and metal sorption capacity was studied in the static method. Adsorption kinetics studies show that <20min was sufficient for >99.99% adsorption of Th(IV) and U(VI). The kinetics for adsorption of U(VI) and Th(IV) was found to follow the first order Lagergren rate kinetics. Adsorption of U(VI) on the malonamide functionalized polymer followed the Langmuir adsorption isotherm. The Langmuir monolayer adsorption phenomenon was also confirmed by the theoretical approach calculated based on the adsorption kinetics. The metal sorption capacities for uranium and thorium were found to be 18.78±1.53mg and 15.74±1.59mg/g of the chelating polymer at 3M HNO3, respectively. [Copyright &y& Elsevier]

Abstract: A resinous functionalized polymer, aniline formaldehyde condensate (AFC) coated on silica gel was used as an adsorbent to remove copper (Cu2+) from aqueous solution under conditions of different initial Cu2+ concentration, adsorbent loading, pH and adsorption time. Coordination bond formation between amine group and Cu2+ ion was the main mechanism of copper removal. Adsorption increased from 20% at pH 4 to 71% at pH 6 due to less competition from proton. Adsorption equilibrium was achieved within 120–150min. The kinetics of adsorption followed second order model with rate constant of 0.0021g/mgmin. The adsorption data gave good fit with Langmuir isotherm and yielded Langmuir monolayer isotherm uptake of 76.33mg/g and adsorption equilibrium parameter of 0.022L/mg at solution pH of 5.4–5.7 and temperature of 22–25°C. During desorption studies 97–100% of adsorbed copper ion released in solution in presence of 1N strength of mineral acids HCl, H2SO4 and HNO3. Dynamic study shows that column breakthrough was achieved at 264 bed volume at initial Cu2+ of 25mg/L. Further studies are recommended on regeneration and reuse of AFC coated silica gel after desorption of copper ion. [Copyright &y& Elsevier]

Abstract: There are reports of taste sensor fabrication by incorporating lipids in a PVC matrix. We have taken an attempt to prepare a taste sensor material by using a functionalized polymer. Polyvinyl alcohol (PVA) has been modified to fabricate the sensor material. The research work covers polymer membrane preparation, morphology study, structural characterization of the membrane, and study of the taste sensing characteristics. The membrane was prepared by cross-linking polyvinyl alcohol with maleic acid. The cross-linked PVA was phosphorylated with POCl3. Polyvinyl alcohol membranes of suitable thickness were thus prepared with a good threshold sensing value and less swelling in water. FTIR spectroscopic analysis, XRD analysis and optical microscopy were done to get an idea about the structure and morphology of the polymer membranes. The sensor characteristics like temporal stability, response stability, response to different taste substances, and reproducibility of sensing performance were studied. The threshold concentrations of the membrane for Q-HCl, HCl, MSG, NaCl and sucrose were 0.01, 0.001, 0.08, 1, and 1mM, respectively. These membrane threshold concentrations are below human threshold concentrations, which are 0.03, 0.9, 1.6, 30 and 170mM for Q-HCl, HCl, MSG, NaCl and sucrose, respectively. [Copyright &y& Elsevier]

Abstract: There are reports of fabrication of taste sensor by adsorbing lipids into Millipore filter paper, which improved the taste sensing efficiency of membrane remarkably. We have made an attempt to prepare taste sensor material by grafting polyacrylic acid (PAA) to cellulose. The research work covers polymer membrane preparation, morphology study, and structural characterization of the membrane and study of the taste sensing characteristics of this membrane for five different taste substances. FTIR spectroscopic analysis and SEM were done to get an idea about the structure and morphology of the PAA grafted cellulose membrane. Surface charge density of the membrane was estimated. The sensor characteristics like temporal stability, response stability, response to different taste substances, and reproducibility of sensing performance were studied using PAA grafted cellulose membrane. Sensor device prepared with this membrane has shown distinct response patterns for different taste substances in terms of membrane potential. Threshold concentrations of PAA grafted cellulose membrane for HCl, NaCl, quinine-hydrochloride (Q-HCl), sucrose and monosodium glutamate are 0.001mM, 0.01mM, 0.08mM, 0.08mM and 0.01mM, respectively. The threshold concentrations except that in Q-HCl are below human threshold concentrations. Membranes also showed characteristic response patterns for organic acids like acetic acid, citric acid, formic acid, etc., mineral acids like HCl, H2SO4 and HNO3, etc., salts, bitter substances, sweet substances and umami substances. Sensor device prepared with this membrane has excellent shelf life. [Copyright &y& Elsevier]

Abstract: A new pyrrole derivative in which an alkyl chain is functionalized with a carboxyl terminal group, (β-pyrrolyl)-octanoic acid, has been electrochemically characterized in propylene carbonate and its irreversible oxidation used to prepare conducting polymer films on platinum. Under potentiostatic control, the data points to an instantaneous nucleation and tri-dimensional growth mechanism. FTIR spectroscopy was used to prove the presence of the carboxyl acid group in the polymeric matrix, crucial feature for future biomolecule immobilization and use of this new polymer in the fabrication of effective biosensors. The voltammetric responses of the polymer modified electrodes present two redox reversible waves which relative importance is film thickness dependent; in all studied cases good stability during repetitive potential cycling was observed. [Copyright &y& Elsevier]

Abstract: There are reports of taste sensor fabrication by incorporation of lipids in a PVC membrane. Such lipid-based sensors were used to evaluate the senses of tastes such as sourness, saltiness, sweetness, bitterness and umami by measuring the membrane potential using Ag/AgCl electrodes. We have measured the senses of above five basic tastes with a functionalized polymer membrane without using any lipid. Commercial cellophane membrane was reacted with POCl3 for conversion to cellophane phosphate. FT-IR spectroscopy and XRD analysis were done to get an idea about the structure and the morphology of the membranes. The sensor characteristics like temporal stability, response stability, response to different taste substances, and reproducibility of sensing performance were studied using both cellophane and cellophane phosphate membranes. The sensor devices prepared with these membranes showed distinct response patterns in terms of membrane potentials for different taste substances. Both the membranes showed reproducible response patterns with a temporal stability of 30min in 1mM KCl solution and a stable response for 5min in 1mM solution of each of the taste substances such as HCl for sourness, NaCl for saltiness, sucrose for sweetness, quinine hydrochloride (Q-HCl) for bitterness and monosodium glutamate (MSG) for umami. The concentration threshold values of these membranes were compared with the human threshold values for the above taste substances. Both the membranes responded to lower threshold concentrations than the human detection limits. The membranes also showed characteristic response patterns for organic and mineral acids. Sensor device prepared with cellophane phosphate membrane has excellent shelf life. [Copyright &y& Elsevier]

Membrane potential measurements were carried out on two conducting polymer film prepared by electropolymerization of two functionalized pyrroles. The Nerstian potential response of both films showed the anion exchanger behavior of the polymers. Donnan dialysis experiments confirmed the transport of the monovalent anion (Cl-/NO3-) through the polymer film, however the transport of the divalent anion (SO42-) is not observed. [Copyright &y& Elsevier]

The well-known polymer, polysulfone (PS), was used, via its carboxylated derivative, as a carrier vehicle for low-molecular weight substances (haptens). The synthesis and characterization of conjugates of PS-CO2H (1) coupled to a relatively non-immunogenic aliphatic hapten (2) or an aromatic hapten (3) and various intermediates in their syntheses, are reported. Immunization with 1, 2, and 3 afforded anti-hapten antibodies and, interestingly, provided evidence for significant adjuvant activity by 1 and related substances. Further studies are called for in order to understand the mechanism of action and correlate immune activity with structure, but these initial results indicate the intriguing possibility of novel immunization methods, free of conventional, toxic adjuvants. [Copyright &y& Elsevier]

There has been increased demand for durable and sustainable construction materials to improve long-term performance of buildings and infrastructure. Polymer modification is a well-known method for improving the properties of construction materials. However, the effectiveness of polymer modification has been limited by the low compatibility between construction materials and polymers, especially polymers from waste plastics and waste rubbers. This paper reviews state-of-the-art studies on compatibilizing polymers via polymer functionalization specifically for thermoplastic and thermosetting polymers. This paper further examines the efficacy of functionalization for enhancing the properties of construction materials. There are three conclusions from this review: (1) Functionalization of polymers by adding various functional groups to their surface can improve the compatibility of polymers and construction materials such as bitumen and concrete. (2) The efficacy of functionalization of a polymer is highly dependent on the grafting material, the grafting degree, and the architecture of the polymer's structure after functionalization. (3) The application of properly functionalized polymers in bitumen and concretes improves their mechanical properties. For instance, it was found that proper functionalization of waste plastics and rubbers can facilitate their use leading to a simultaneous solution for enhancing durability and sustainability of the built environment and addressing environmental concerns associated with the accumulation of those wastes in landfills. The study further identifies knowledge gaps pertaining to an in-depth understanding of polymer functionalization specifically tailored to construction materials and the need for associated life-cycle assessments. Addressing these gaps will facilitate the generation of value-added applications for waste polymeric materials to promote resource conservation and sustainability. [Display omitted] [ABSTRACT FROM AUTHOR]