Preparation, morphologies, and properties of positively charged quaternized poly(phthalazinone ether sulfone ketone) nanofiltration membranes

Abstract

Positively charged quaternized poly(phthalazinone ether sulfone ketone) (QAPPESK) nanofiltration (NF) membranes were prepared from chloromethylated poly(phthalazinone ether sulfone ketone) by the dye/wet phase inversion method with N-methyl-2-pyrrolidone (NMP) and N,N-dimethylacetamide (DMAc) as solvents. The effects of the ratio of NMP to DMAc, the evaporation time, the evaporation temperature, and the coagulation temperature on membrane performance were evaluated by the orthogonal design method. The results showed that the optimal preparation conditions were an NMP/ DMAc ratio of 2/8, an evaporation time of 5 min at 70 C, and a coagulation temperature lower than 5 C. The effects of the additive type and concentration on the QAPPESK NF membrane cross-section morphology and performance were investigated in detail. Furthermore, QAPPESK NF membranes exhibited good thermal stability with stable membrane performance for 120 h at 60 C.

Preparation of a positively charged nanofiltration membrane based on hydrophilic–hydrophobic transformation of a poly(ionic liquid)

“…Charged nanoltration (NF) membranes usually have a good separation performance for small size electrolytes due to the steric effect and unique Donnan effect. [1][2][3][4][5][6][7][8][9][10][11][12][13] As a benet of their hydrophilicity, charged NF membranes usually have high permeability. Meanwhile the charge repulsion effect endows the NF membrane with a good anti-fouling performance.…”

“…Various methods have been applied to design charged NF membranes, including interfacial polymerization (IP), 1,2 phase inversion, [3][4][5][6] surface graing, 7,8 chemical cross-linking, [9][10][11] and layer-by-layer assembly. 12,13 IP is an important method to prepare NF membranes which possess a wonderful performance and are applied in various water treatment processes.…”

“…Therefore, researchers have made great efforts to nd a benign way to prepare positively charged membranes. Long chain chloromethyl ethers with less toxicity and low volatility, such as chloromethyl butyl ether, 3 and chloromethyl octyl ethers, 4,5 were used to replace chloromethyl methyl ether. An alternative way is directly employing the chloromethylated polymer/copolymer, such as the polymerization of chloromethylstyrene.…”

Poly(arylene ether sulfone) containing thioether units: synthesis, oxidation and properties

“…Our interest is focused on the improvement of corrosion resistance and thermal properties of PAES. In recent decades, these approaches had been reported, Jian developed a kind of membrane materials containing aromatic heterocycle, [23][24][25] Shin and Bottino synthesized a new kind of materials with polycyclic, 26,27 Park etc. developed a kind of poly(arylene ether sulfone) containing amide group.…”