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Brucite was modified with oleic acid (OA) and the effect of OA on flame retardancy of brucite in low‐density polyethylene (LDPE) composites was investigated. Fourier transform infrared spectroscopy, X‐ray diffraction, and particle size analysis were used to examine the structural changes of the OA modified brucite. Flammability of the LDPE/brucite composites with different OA content was characterized by thermogravimetric analysis, limiting oxygen index (LOI), UL‐94 test, and microscale combustion calorimetry. The results showed that when brucite was modified with OA, magnesium oleate was formed on the brucite surface. The brucite particle size and the relative intensity of the (101) diffraction peak of brucite decreased. When the content of OA and brucite in the composite were 6 and 40 phr respectively, the prepared LDPE composite displayed better flame retardancy than the corresponding OA free LDPE composite: the LOI value increased from 22.2% to 24.9%, and the peak heat release rate decreased from 678 to 546 kW/m2. The influence of OA on the improvement of flame retardancy of brucite in LDPE/brucite composite was due to the efficient dispersion of brucite in LDPE matrix and the structural changes of brucite, caused by the reaction of OA with brucite. [ABSTRACT FROM AUTHOR]

In this work, polyvinylidene fluoride‐boron carbide mixed matrix membranes were synthesized via phase inversion method. The synthesized membranes were characterized using field emission scanning electron microscopy, X‐ray diffraction spectroscopy, energy dispersive spectroscopy, porosity, and contact angle. The mixed matrix membranes (0–5 wt.% of boron carbide) were tested for ultrafiltration of bovine serum albumin solution and photodegradation property using rhodamine B and methylene blue dyes. The morphological images reveal the existence of boron carbide particles on the surface of the membranes. Upon introduction of B4C particles, the performance of the membranes was improved: permeate flux increases from 163.13 to 351.15 L/m2 h; bovine serum albumin rejection increased from 77.1% to 99.1%; relative flux reduction decreased from 45.58% to 16.06%; flux recovery ratio increased from 61.71% to 98.42%. Furthermore, maximum photodegradation yield was observed for membranes with 4 wt.% boron carbide particles with degradation efficiency of 96.7% and 96% for rhodamine B and methylene blue dyes, respectively. Furthermore, the rate constant of the optimum membrane was higher than the pristine membrane (about 2.05 and 2.26 times higher for rhodamine B and methylene blue dyes, respectively). Indeed, the mixed matrix membranes present a great prospect for the photodegradation of organic dyes. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, antifouling membranes were prepared through dry wet-phase inversion method. The incorporation of electrostatistically charged group of sulfonate cation exchange resins (SCER) into polyethersulfone membrane matrix attempts to give a synergistic combination of properties for bovine serum albumin (BSA) removal. The effect of different composition of SCER into the blend membranes were characterized using scanning electron microscopy, atomic force microscopy, porosimeter, attenuated total reflectance Fourier transform infrared spectroscopy, and goniometer. All the prepared membranes were evaluated for BSA separation. The membrane resistance of all membranes decreases with increase in SCER loading. Among all membranes, P3 membrane shows a better fouling, reversible and irreversible resistance for BSA, signifying that the attached BSA on the membrane surface can be easily removed by physical cleaning. The improvement in hydrophilicity of P3 membrane was found to be the dominant factor in mitigating BSA fouling. The results demonstrated that BSA fouling could be alleviated by varying SCER concentration in the polyethersulfone matrix. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45854. [ABSTRACT FROM AUTHOR]

TiO2 is a semiconductor material with high chemical stability and low toxicity. It is widely used in the fields of catalysis, sensing, hydrogen production, optics and optoelectronics. However, TiO2 photocatalyst is sensitive to ultraviolet (UV) light; this is why its photocatalytic activity and quantum efficiency are reduced. To enhance the photocatalytic efficiency in the visible light range as well as to increase the number of the active sites on the crystal surface or inhibit the recombination rate of photogenerated electron–hole pairs electrons, various metal ions were used to modify TiO2. This review paper comprehensively summarizes the latest progress on the modification of TiO2 photocatalyst by a variety of metal ions. Lastly, the future prospects of the modification of TiO2 as a photocatalyst are proposed. [ABSTRACT FROM AUTHOR]

In the present work, a highly efficient mixed matrix membrane (MMM) for humic acid (HA) removal was developed. Multiwalled carbon nanotubes (MWCNTs) were functionalized in the presence of 3-methacryloxypropyl trimethoxysilane using the co-condensation method and were subsequently loaded with TiO2 (prepared via the sol–gel route). The as-prepared material was then incorporated into a PES polymer solution to prepare a fMWCNT-TiO2/PES hybrid membrane via non-solvent induced phase inversion. The microstructure of the membrane was characterized using Fourier transform infrared spectroscopy, atomic force microscopy, scanning electron microscopy, water contact angle, thickness, porosity, and pore size. The fMWCNT-TiO2/PES hybrid membrane was tested for the removal of HA and antifouling performance. The results show that the surface hydrophilicity of the membranes was greatly improved upon the addition of the fMWCNT-TiO2 particles. The results show that 92% of HA was effectively removed after 1 h of filtration. In comparison with pristine membrane, the incorporation of fMWCNT-TiO2 nanoparticles led to enhanced pure water flux (99.05 L/m2 h), permeate flux (62.01 L/m2 h), higher HA rejection (92%), and antifouling improvement (RFR: 37.40%, FRR: 86.02%). Thus, the fMWCNT-TiO2/PES hybrid membrane is considered to be a great potential membrane for the improvement of ultrafiltration membranes. [ABSTRACT FROM AUTHOR]