A series of novel double perovskite oxides NaMTi<Subscript>2</Subscript>O<Subscript>6</Subscript> (M = Eu,Sm, and Gd): preparation,characterization and photocatalytic studies under visible and solarlight irradiation

The photocatalytic activity of sol–gel synthesized double perovskite type oxides NaEuTi₂O₆(NETO), NaSmTi₂O₆ (NSTO), and NaGdTi₂O₆ (NGTO) powders on degradation of methylene blue (MB) dye was demonstrated for the first time under visible light as well as sunlight irradiation. The obtained samples were characterized by X-ray diffraction, UV–Visible diffuse reflectance spectroscopy and scanning electron microscopy equipped with X-ray energy-dispersion spectrometry. All the three samples have shown photocatalytic activity for degradation of MB under sunlight and visible light irradiation and their photocatalytic activity followed the order of NGTO > NETO > NSTO. The superior activity of NGTO is ascribed to the higher amount of hydroxyl radicals generated in the photocatalytic reaction.     

Efficient adsorptive extraction materials by surface protein-imprinted polymer over silica gel for selective recognition/separation of human serum albumin from urine

In this study, we report the development of adsorptive extraction materials by surface protein-imprinted polymers (MIPs) over silica gel for selective recognition/separation of human serum albumin (HSA) from urine. The HSA-imprinted polymers prepared on silica particle had at interface between the silica gel and different MIPs greatly produced enrichment for the binding of protein from the urine. The solid-phase extraction of the optimized polymer layer was prepared by copolymerization of methacrylic acid (MAA), acrylamide (AAm), and dimethylaminoethylmethacrylate (DMAEMA) and a crosslinker methylenebisacrylamide (MBA) at the mole ratio of 1:158:88 (T:M:C) and showed moderate affinity (<10⁴ order M⁻¹) toward target protein HSA and selectivity. Four analogues, egg white albumin (EWA), bovine serum albumin (BSA), lysozyme (Lyz), and creatinine (Cre) were selected to study the binding efficiency of MIPs in single and binary protein solutions. We studied the influence on recognition ability for HSA and found that prepolymer mixture and matrix flexibility of the optimized thin polymer layer (35 ± 10 nm) on the submicrosilica particles. The high-binding affinity (Q_MIP, 86.7 mg g⁻¹) and fast kinetics (180 min) were observed for this synthesized HSA-MIP when compared with other reported HSA-MIPs in surface imprinting (5.9 and 11.3 mg g⁻¹) and epitope surface imprinting (46.6 mg g⁻¹) methods. We demonstrated the application in real and synthetic urine samples that the approach allowed the efficient adsorption of HSA in real urine (129.48 mg g⁻¹) is almost double to the binding of HSA in synthetic urine (67.84 mg g⁻¹). Apart from this, only minor interference of Cre (2.74 mg g⁻¹) was observed, eventhough Cre is the final metabolite in urine. These adsorptive submicrosilica materials have potential in the pharmaceutical industry and clinical analysis applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46894.     

Synthesis and characterization of new fluorine-containing polyethers

A highly fluorinated monomer, 1,3-bis(1,1,1,3,3,3-hexafluoro-2-pentafluorophenylmethoxy-2-propyl)benzene (12F-FBE), is obtained by reaction of the sodium salt of 1,3-bis(1,1,1,3,3,3-hexafluoro-2-hydroxy-2-propyl)benzene with pentafluorobenzyl bromide. 12F-FBE reacts with diphenols to give soluble, hydrophobic, low dielectric (2.30-2.43 at 10 GHz) polyethers. Thermal stability as measured by TGA (10 wt% loss) is moderate and ranges from 445 to 464 °C in air. Glass transition temperatures are between 89 and 110 °C.     

Connection of surface tension with multiple tribological properties in epoxy + fluoropolymer systems

Contact angles of free liquids on solid samples were measured and the van Oss–Good method was applied for evaluating surface tensions of the solids. A parachor method was used for comparison: in this case the respective values were calculated for the polymer solids from molecular and group contributions. Surface tensions were computed from the parachors and the two methods compared. Effects of varying the fluoropolymer added to the epoxy before curing are discussed. For a given fluoropolymer, effects of changing its concentration on surface tension have also been evaluated and compared to the changes in scratch resistance (scratch penetration depth, recovery depth) and in static and dynamic friction. Morphological and phase structure changes are reflected in all these properties, showing a strong connection between the surface tension and tribological properties. Copyright © 2003 Society of Chemical Industry     

New spirodilactam polymers

New polyether and poly(ether ketone)s containing the rigid 1,6-diazaspiro[4.4]nonane-2,7-dione (spirodilactam) core in the backbone are described. The polymers are soluble in common solvents from which clear, colorless films are readily cast. Excellent thermo-oxidative stability is shown by all of the systems studied with TGA stabilities up to 595 °C or 598 °C in air and argon respectively. Dielectric constants ranged from 2.53 to 3.00 and water absorption results were nil to 3.6%.