Enhanced room-temperature magnetoresistance in self-assembled Ag-coated multiphasic chromium oxide nanocomposites

Self-assembled Ag-coated multiphasic diluted magnetic chromium oxide nanocomposites were developed by a facile chemical synthesis route involving a reaction of CrO3 in the presence of Ag+ ions in an aqueous solution of poly-vinyl alcohol (PVA) and sucrose.

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The Synthesis of Poly(Vinyl Alcohol) Grafted with Fluorinated Protic Ionic Liquids Containing Sulfo Functional Groups

Molecules ◽

10.3390/molecules26144158 ◽

2021 ◽

Vol 26 (14) ◽

pp. 4158

Author(s):

Patrycja Glińska ◽

Andrzej Wolan ◽

Wojciech Kujawski ◽

Edyta Rynkowska ◽

Joanna Kujawa

Keyword(s):

Ionic Liquids ◽

Vinyl Alcohol ◽

Proton Exchange ◽

Polymer Materials ◽

Polymerization Reaction ◽

Poly Vinyl Alcohol ◽

Hydroxyl Groups ◽

Protic Ionic Liquids ◽

Synthesis Route ◽

Sulfo Groups

There has been an ongoing need to develop polymer materials with increased performance as proton exchange membranes (PEMs) for middle- and high-temperature fuel cells. Poly(vinyl alcohol) (PVA) is a highly hydrophilic and chemically stable polymer bearing hydroxyl groups, which can be further altered. Protic ionic liquids (proticILs) have been found to be an effective modifying polymer agent used as a proton carrier providing PEMs’ desirable proton conductivity at high temperatures and under anhydrous conditions. In this study, the novel synthesis route of PVA grafted with fluorinated protic ionic liquids bearing sulfo groups (–SO3H) was elaborated. The polymer functionalization with fluorinated proticILs was achieved by the following approaches: (i) the PVA acylation and subsequent reaction with fluorinated sultones and (ii) free-radical polymerization reaction of vinyl acetate derivatives modified with 1-methylimidazole and sultones. These modifications resulted in the PVA being chemically modified with ionic liquids of protic character. The successfully grafted PVA has been characterized using 1H, 19F, and 13C-NMR and FTIR-ATR. The presented synthesis route is a novel approach to PVA functionalization with imidazole-based fluorinated ionic liquids with sulfo groups.

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Multiporous open-cell poly(vinyl formal) foams for sound absorption

RSC Advances ◽

10.1039/c5ra23285f ◽

2016 ◽

Vol 6 (9) ◽

pp. 7653-7660 ◽

Cited By ~ 12

Author(s):

Bai Xue ◽

Jianguo Deng ◽

Junhua Zhang

Keyword(s):

Aqueous Solution ◽

Vinyl Alcohol ◽

Sound Absorption ◽

Poly Vinyl Alcohol ◽

Open Cell

A series of multiporous open-cell poly(vinyl formal) (PVF) foams were obtained by crosslinking poly(vinyl alcohol) (PVA) with different contents of formaldehyde in aqueous solution.

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Antibacterial property and biocompatibility of Chitosan/Poly(vinyl alcohol)/ZnO (CS/PVA/ZnO) beads as an efficient adsorbent for Cu(II) removal from aqueous solution

Colloids and Surfaces B Biointerfaces ◽

10.1016/j.colsurfb.2017.05.028 ◽

2017 ◽

Vol 156 ◽

pp. 340-348 ◽

Cited By ~ 14

Author(s):

Jiao Xu ◽

Yaping Zhang ◽

Yuvaraja Gutha ◽

Weijiang Zhang

Keyword(s):

Aqueous Solution ◽

Vinyl Alcohol ◽

Antibacterial Property ◽

Poly Vinyl Alcohol ◽

Efficient Adsorbent

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Novel pH-Sensitive Poly(Vinyl Alcohol) Based Polyampholyte as Pervaporation Membrane

Materials Science Forum ◽

10.4028/www.scientific.net/msf.852.979 ◽

2016 ◽

Vol 852 ◽

pp. 979-983

Author(s):

Ping Rui Meng ◽

Liang Bo Li

Keyword(s):

Aqueous Solution ◽

Vinyl Alcohol ◽

Water Resistance ◽

Graft Copolymerization ◽

Sodium Acrylate ◽

Poly Vinyl Alcohol ◽

Permeate Flux ◽

Ft Ir ◽

Ethanol Aqueous Solution ◽

Poly Acrylamide

Sodium acrylate (NaAA) and acrylamide (AM) were grafted onto poly (vinyl alcohol) (PVA) using potassium persulfate as an initiator, Graft copolymerization namely poly (vinyl alcohol)-g-poly (acrylamide/sodium acrylate) (PVA-g-PAM/SAC). The poly (vinyl alcohol)-g-poly (vinylamine/sodium acrylate) (PVAMC) was prepraed by Hofmann rearrangement.The PVAMC homogeneous membrane was characterized by fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM).The water resistance of the PVAMC membranes is the best when pH of the PVAMC solutions was 4, at that time the numbers of-NH3+ and-COO- groups trended to be equal, so the isoelectric point was pH=4. At 90 °C the pervaporation of PVAMC composite membrane was tested and showed that the separation factor and the permeate flux were about 1001 and 1341 g/(m2·h) for 90wt% ethanol aqueous solution, and they were about 1297 and 1040 g/(m2·h) for 90wt% isopropanol aqueous solution.

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