The impact of poly (ionic liquid) on the phosphoric acid stability of polybenzimidazole-base HT-PEMs

2021 ◽  
Vol 163 ◽  
pp. 1692-1700
Author(s):  
Fengxiang Liu ◽  
Shuang Wang ◽  
Hao Chen ◽  
Jinsheng Li ◽  
Xu Wang ◽  
...  
RSC Advances ◽  
2022 ◽  
Vol 12 (3) ◽  
pp. 1777-1787
Author(s):  
Zehui Xiang ◽  
Fan Hu ◽  
Xueyan Wu ◽  
Fugang Qi ◽  
Biao Zhang ◽  
...  

Schematic diagram of multi-walled carbon nanotube composite ionic liquid synergistically enhancing the high-speed impact resistance of polyurethane elastomer.


Nanomaterials ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 749 ◽  
Author(s):  
Jianxia Nie ◽  
Songhua Xiao ◽  
Rou Tan ◽  
Taihong Wang ◽  
Xiaochuan Duan

The swelling mechanism is widely used to explain the response of ionic liquids (ILs) or poly(ionic liquid)s (PILs) to moisture. While a fairly broad consensus has been attained, there are still some phenomena that are not well explained. As a complement to the swelling mechanism, we systematically studied the free volume theory in the rapid response and recovery of PIL humidity performance. We chose poly(1-ethyl-3-vinylimidazolium bromide) (PIL-Br), poly(1-ethyl-3-vinylimidazolium tetrafluoroborate) (PIL-BF4) and poly(1-ethyl-3-vinylimidazolium bis(trifluoromethane sulfonimide)) (PIL-TFSI) as model materials and investigated the impact of PIL structure including anion type, film thickness and affinity to moisture on performance to obtain the humidity sensing mechanism for PILs based on free volume theory. Hence, we can combine free volume theory with the designed PIL structures and their affinity with moisture to obtain a high concentration of free ions in PIL sensing films. Furthermore, the PIL humidity sensors also show fast, substantial impedance changes with changing humidity for real-time monitoring of the human respiratory rate due to a fast response and recovery performance. Therefore, our findings develop a new perspective to understand the humidity performance of PILs based on free volume theory, resulting in fast response and recovery properties realized by the rational design of PIL sensing films.


Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3146
Author(s):  
Łukasz Nuckowski ◽  
Krzysztof Dzieszkowski ◽  
Zbigniew Rafiński ◽  
Sylwia Studzińska

Magnetic nanoparticles coated with zwitterionic poly(ionic liquid)s were applied for dispersive solid-phase extraction of oligonucleotides. The materials were synthesized by miniemulsion copolymerization of ionic liquids and divinylbenzene on magnetic nanoparticles. The functional monomers contain a positively charged imidazolium ring and one of the anionic groups: derivatives of acetate, malonate, or butyl sulfonate ions. Adsorption of unmodified DNA oligonucleotide on obtained materials was possible in ion-exchange (IE) and hydrophilic interactions (HI) mode. The adsorption in IE was possible at low pH and was almost complete. The adsorption in HI mode required the usage of appropriate addition of organic solvent but did not provide full adsorption. Studies on the desorption of the analytes included determining the impact of ammonium acetate concentration and pH and organic solvents addition on the recovery. The material containing acetic fragments as an anionic group was selected for the final procedure with the use of 10 mM ammonium acetate (pH = 9.5)/methanol (50/50, v/v) as an elution solution. The magnetic dispersive solid-phase extraction procedure was tested for the oligonucleotides with various modifications and lengths. Moreover, it was applied to extract DNA oligonucleotide and its synthetic metabolites from enriched human plasma without any pre-purification, with recoveries greater than 80%.


Author(s):  
Ramchandra Gawas ◽  
Rui Sun ◽  
Yawei Li ◽  
Kenneth C. Neyerlin ◽  
Yossef Elabd ◽  
...  

Abstract Ionic liquid (IL) additives to both traditional and advanced oxygen reduction reaction (ORR) electrocatalysts have yielded remarkable improvements in catalyst performance and durability. However, incorporating ILs or IL-modified catalysts into the electrodes of a proton exchange membrane fuel cell (PEMFC) membrane electrode assembly (MEA) has proven to be challenging. Sulfonated poly(ionic liquid) block copolymers (S-PILBCP) present an opportunity to incorporate IL functionality directly into the ionomer, orthogonal to protonic conductivity. Here, we use a rotating disc electrode (RDE) to characterize the interface between a S-PILBCP and Pt catalyst in comparison to Nafion. Catalyst thin films prepared with S-PILBCP show an 80% improvement in the ORR activity over those containing Nafion. Thin films of S-PILBCP also show a significantly reduced degree of poisoning sulfonate adsorption on a Pt(111) surface in comparison to Nafion. These half-cell results provide useful insights that help to highlight the source of the impact of the S-PILBCP on PEMFC MEA performance.


Author(s):  
Wenxin Wei ◽  
Guifeng Ma ◽  
Hongtao Wang ◽  
Jun Li

Objective: A new poly(ionic liquid)(PIL), poly(p-vinylbenzyltriphenylphosphine hexafluorophosphate) (P[VBTPP][PF6]), was synthesized by quaternization, anion exchange reaction, and free radical polymerization. Then a series of the PIL were synthesized at different conditions. Methods: The specific heat capacity, glass-transition temperature and melting temperature of the synthesized PILs were measured by differential scanning calorimeter. The thermal conductivities of the PILs were measured by the laser flash analysis method. Results: Results showed that, under optimized synthesis conditions, P[VBTPP][PF6] as the thermal insulator had a high glass-transition temperature of 210.1°C, high melting point of 421.6°C, and a low thermal conductivity of 0.0920 W m-1 K-1 at 40.0°C (it was 0.105 W m-1 K-1 even at 180.0°C). The foamed sample exhibited much low thermal conductivity λ=0.0340 W m-1 K-1 at room temperature, which was comparable to a commercial polyurethane thermal insulating material although the latter had a much lower density. Conclusion: In addition, mixing the P[VBTPP][PF6] sample into polypropylene could obviously increase the Oxygen Index, revealing its efficient flame resistance. Therefore, P[VBTPP][PF6] is a potential thermal insulating material.


2021 ◽  
Vol 6 (15) ◽  
pp. 3795-3801
Author(s):  
Radostina Kalinova ◽  
Ivaylo Dimitrov ◽  
Christo Novakov ◽  
Svetlana Veleva ◽  
Antonia Stoyanova

Nanoscale ◽  
2021 ◽  
Author(s):  
Ning Gao ◽  
Kang Zhou ◽  
Kai Feng ◽  
Wanlin Zhang ◽  
Jiecheng Cui ◽  
...  

Micellar and vesicular structures capable of sensing and reporting the chemical environment as well as facilely introducing user-defined functions make a vital contribution to constructing versatile compartmentalized systems. Herein, combing...


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