In this work, a new type of composite nanoparticles, 'pearl chain', was developed by linking titanium dioxide and silicon dioxide by polyacrylic acid polymer chains, and the prepared TiO-PAA-SiO composite nanoparticles were analysed by SEM, Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy and thermogravimetric analysis, zeta potential, x-ray diffraction, etc. The success of this work was verified by the successful linking of TiO-PAA-SiO composite nanoparticles.TiO-PAA-SiO composite nanoparticles were analysed to verify the successful attachment of pearl chains.
View Article and Find Full Text PDFThe ability of membranes to separate oil vapour is affected by their permeance and selectivity. This study modifies polyether block amide (PEBA) composite membranes with a microporous zeolite, Silicalite-1, or a mesoporous zeolite, MCM-41. The results show that when PEBA composite membranes are modified with these zeolites, the selective layer of the composite membrane is coated more thinly, resulting in a higher flux of organic gas.
View Article and Find Full Text PDFMembranes (Basel)
August 2022
In this paper, the compatibility of polyetherimide (PEI) with different contents as a high-performance copolymer and polyvinylidene fluoride (PVDF) was studied, and 5%-20% PEI was prepared by the non-solvent-induced phase inversion method. The compatibility of PVDF and PEI was evaluated by analyzing the physical structure and properties of the blend membrane, the microstructure, the glass transition temperature Tg, the enthalpy, and the mechanism of the polymer blend enthalpy change. The results show that the blend membranes have -NH and C=O-N binding energies at X-ray photoelectron spectroscopy (XPS), which preliminarily proves that fluorine-amine bonds are formed between the polymers, and new spectra appeared by Fourier transform infrared (FTIR) and X-ray diffraction (XRD) peaks, which further proves that the two have the formation of fluorine-amine bonds, the Tg and enthalpy of the mixed membrane was increased, and a scanning electron microscope (SEM) observed that the membrane pores changed from finger-like pores to sponge-like macropores.
View Article and Find Full Text PDFPolymers (Basel)
July 2022
The development of high-performance polymer membranes has sparked a lot of attention in recent years. Polymer blending is a potential method of modification. A limitation, however, is the compatibility of blends at the molecular level.
View Article and Find Full Text PDFImproving the contamination resistance of membranes is one of the most effective ways to address the short service life of membranes. While preparing the membrane system structure, doping nanoparticles into the polymer matrix is beneficial to the preparation of high-performance membranes. To develop a new structure for membrane contamination protection, in this study, a novel asymmetric polyamide 66 composite ultrafiltration (UF) membrane was fabricated by incorporating different masses (ranging from zero to 0.
View Article and Find Full Text PDFPolyamide 66 microporous membranes were prepared by cold non-solvent-induced phase separation using polyamide 66-formic acid-propylene carbonate as a ternary membrane-forming system. The formed membranes exhibited a special bicontinuous structure consisting of interglued spherical crystals or interlocked bundles of microcrystalline aggregates. The variation of the microporous structure under the influence of preparation conditions, solvent, aging time, and polymer concentration affects the comprehensive performance of the membranes.
View Article and Find Full Text PDFComposite membranes were fabricated with polyethersulfone as a microporous substrate and polyether block amide (PEBA) as a selective layer to achieve efficient recovery of volatile organic compounds (VOCs). Fumed silica was mixed into PEBA for modification. The top thin layers with different percentage of fumed silica in PEBA were prepared by spin-coating.
View Article and Find Full Text PDFJ Environ Sci (China)
July 2007
Concentration polarization and membrane fouling remain one of the major hurdles for the implementation of ultrafiltration of produced water. Although many applications for ultrafiltration were already suggested, only few were implemented on an industrial scale. Among those techniques, turbulence promoter can be more simple and effective in overcoming membrane fouling and enhancing membrane flux.
View Article and Find Full Text PDF