共查询到20条相似文献,搜索用时 15 毫秒
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Dr. Cher Hon Lau Dr. Phuc Tien Nguyen Dr. Matthew R. Hill Dr. Aaron W. Thornton Dr. Kristina Konstas Dr. Cara M. Doherty Dr. Roger J. Mulder Dr. Laure Bourgeois Dr. Amelia C. Y. Liu Dr. David J. Sprouster Prof. James P. Sullivan Dr. Timothy J. Bastow Dr. Anita J. Hill Prof. Douglas L. Gin Prof. Richard D. Noble 《Angewandte Chemie (International ed. in English)》2014,53(21):5322-5326
Aging in super glassy polymers such as poly(trimethylsilylpropyne) (PTMSP), poly(4‐methyl‐2‐pentyne) (PMP), and polymers with intrinsic microporosity (PIM‐1) reduces gas permeabilities and limits their application as gas‐separation membranes. While super glassy polymers are initially very porous, and ultra‐permeable, they quickly pack into a denser phase becoming less porous and permeable. This age‐old problem has been solved by adding an ultraporous additive that maintains the low density, porous, initial stage of super glassy polymers through absorbing a portion of the polymer chains within its pores thereby holding the chains in their open position. This result is the first time that aging in super glassy polymers is inhibited whilst maintaining enhanced CO2 permeability for one year and improving CO2/N2 selectivity. This approach could allow super glassy polymers to be revisited for commercial application in gas separations. 相似文献
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Metal–organic framework (MOF)/polymer mixed matrix membranes (MMMs) have received significant interest in the last decade. MOFs are incorporated into polymers to make MMMs that exhibit improved gas permeability and selectivity compared with pure polymer membranes. The fundamental challenge in this area is to choose the appropriate MOF/polymer combinations for a gas separation of interest. Even if a single polymer is considered, there are thousands of MOFs that could potentially be used as fillers in MMMs. As a result, there has been a large demand for computational studies that can accurately predict the gas separation performance of MOF/polymer MMMs prior to experiments. We have developed computational approaches to assess gas separation potentials of MOF/polymer MMMs and used them to identify the most promising MOF/polymer pairs. In this Personal Account, we aim to provide a critical overview of current computational methods for modeling MOF/polymer MMMs. We give our perspective on the background, successes, and failures that led to developments in this area and discuss the opportunities and challenges of using computational methods for MOF/polymer MMMs. 相似文献
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Kaoping Song Jianwen Tao Xiuqin Lyu Yang Xu Shaopeng Liu Zhengbo Wang Huifeng Liu Yuxuan Zhang Hongtao Fu En Meng Mingxi Liu Hu Guo 《Molecules (Basel, Switzerland)》2022,27(20)
Polymer flooding is drawing lots of attention because of the technical maturity in some reservoirs. The first commercial polymer flooding in China was performed in the Daqing oilfield and is one of the largest applications in the world. Some laboratory tests from Daqing researchers in China showed that the viscoelasticity of high molecular weight polymers plays a significant role in increasing displacement efficiency. Hence, encouraged by the conventional field applications and new findings on the viscoelasticity effect of polymers on residual oil saturation (ROS), some high-concentration high-molecular-weight (HCHMW) polymer-flooding field tests have been conducted. Although some field tests were well-documented, subsequent progress was seldom reported. It was recently reported that HCHMW has a limited application in Daqing, which does not agree with observations from laboratory core flooding and early field tests. However, the cause of this discrepancy is unclear. Thus, a systematic summary of polymer-flooding mechanisms and field tests in China is necessary. This paper explained why HCHMW is not widely used when considering new understandings of polymer-flooding mechanisms. Different opinions on the viscoelasticity effect of polymers on ROS reduction were critically reviewed. Other mechanisms of polymer flooding, such as wettability change and gravity stability effect, were discussed with regard to widely reported laboratory tests, which were explained in terms of the viscoelasticity effects of polymers on ROS. Recent findings from Chinese field tests were also summarized. Salt-resistance polymers (SRPs) with good economic performance using produced water to prepare polymer solutions were very economically and environmentally promising. Notable progress in SRP flooding and new amphiphilic polymer field tests in China were summarized, and lessons learned were given. Formation blockage, represented by high injection pressure and produced productivity ability, was reported in several oil fields due to misunderstanding of polymers’ injectivity. Although the influence of viscoelastic polymers on reservoir conditions is unknown, the injection of very viscous polymers to displace medium-to-high viscosity oils is not recommended. This is especially important for old wells that could cause damage. This paper clarified misleading notions on polymer-flooding implementations based on theory and practices in China. 相似文献
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Summary: Hydrogen can be separated from its mixtures using polymer foams with closed cells. Each cell serves as a gas container which is filled through its walls – separation membranes. Foam, as a manifold membrane system, utilizes transient states of permeation and thus takes advantage of fastest diffusion of hydrogen. Large scale manufactured polystyrene foams were chosen to demonstrate the phenomenon. Novel proton conducting membranes containing ionic liquids are being developed. They can perform in intermediate-temperature fuel cells (FC). 相似文献
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降低工业分离过程的能耗为缓解全球能源紧缺问题提供了有效途径. 相比传统工业分离技术, 膜分离技术能耗低、经济效益高, 开发高效的膜材料是提升膜分离性能的重要手段. 共轭微孔聚合物(CMP)膜具有刚性永久超微孔道、高孔隙率、孔结构及化学环境可调控、交联骨架稳定性好等优势, 在分离领域具有良好的应用前景. 概述了近年来CMP膜的制备方法并简要对比了其优缺点, 阐述了CMP膜在气体分离、有机溶剂纳滤、离子筛分和手性分离等领域的分离机理和研究进展, 为开发新型具有良好分离性能的CMP膜材料提供研究思路. 相似文献
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Fernando Cacho‐Bailo Dr. Carlos Téllez Prof. Dr. Joaquín Coronas 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(28):9533-9536
Polymeric membranes are important tools for intensifying separation processes in chemical industries, concerning strategic tasks such as CO2 sequestration, H2 production, and water supply and disposal. Mixed‐matrix and supported membranes have been widely developed; recently many of them have been based on metal–organic frameworks (MOFs). However, most of the impacts MOFs have within the polymer matrix have yet to be determined. The effects related to thermal behavior arising from the combination of MOF ZIF‐8 and polysulfone have now been quantified. The catalyzed oxidation of the polymer is strongly affected by the MOF crystal size and distribution inside the membrane. A 16 wt % 140 nm‐sized ZIF‐8 loading causes a 40 % decrease in the observed activation energy of the polysulfone oxidation that takes place at a temperature (545 °C) 80 °C lower than in the raw polymer (625 °C). 相似文献
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Block Copolymer‐Derived Monolithic Polymer Films and Membranes Comprising Self‐Organized Cylindrical Nanopores for Chemical Sensing and Separations 下载免费PDF全文
Prof. Dr. Takashi Ito 《化学:亚洲杂志》2014,9(10):2708-2718
Microphase separation of block copolymers (BCPs) has been extensively studied because it leads to the self‐assembled formation of periodic structures controlled on the scale of tens of nanometers. In particular, BCP‐derived cylindrical microdomains have attracted considerable interest for various applications owing to their well‐defined shapes of uniform and tunable diameters. This focus review highlights recent efforts to apply BCP‐derived monolithic films/membranes comprising cylindrical nanopores for chemical sensing and separations. The nanopores provide confined molecular pathways that exhibit enhanced selectivity based on steric, electrostatic, and chemical interactions, and thus, enable us to design unique electrochemical sensors and highly efficient separation membranes. 相似文献
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药物氟哌酸分子印迹聚合物膜的制备及其渗透性质研究 总被引:11,自引:0,他引:11
以聚偏氟乙烯微孔滤膜为支撑膜,氟哌酸为模板分子,用紫外光引发原位聚合方法制备了分子印迹聚合物膜.研究了模板分子与功能单体之间的相互作用,用扫描电镜表征了膜的表面形貌.混合底物渗透实验结果表明,分子印迹聚合物膜中存在着由形状和功能基团均与模板分子氟哌酸相互补的孔穴组成的通道,该通道可选择性地富集底物分子. 相似文献
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燃料电池聚合物电解质膜 总被引:1,自引:0,他引:1
本文简要介绍了聚电解质膜燃料电池的定义、分类、工作原理及其特点,综述了国内外在燃料电池聚电解质领域的最新成果。对质子传导率与甲醇渗透系数的关系进行了初步探讨,详细评述了近年来AAPEM和ACPEM这两类聚电解质膜的研究进展,并对今后的研究趋势作了展望。 相似文献
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Guangwu Li Chong Kang Cuihong Li Zhen Lu Jicheng Zhang Xue Gong Guangyao Zhao Huanli Dong Wenping Hu Zhishan Bo 《Macromolecular rapid communications》2014,35(12):1142-1147
Four novel conjugated polymers ( P1‐4 ) with 9,10‐disubstituted phenanthrene (PhA) as the donor unit and 5,6‐bis(octyloxy)benzothiadiazole as the acceptor unit are synthesized and characterized. These polymers are of medium bandgaps (2.0 eV), low‐lying HOMO energy levels (below −5.3 eV), and high hole mobilities (in the range of 3.6 × 10−3 to 0.02 cm2 V−1 s−1). Bulk heterojunction (BHJ) polymer solar cells (PSCs) with P1‐4 :PC71BM blends as the active layer and an alcohol‐soluble fullerene derivative (FN‐C60) as the interfacial layer between the active layer and cathode give the best power conversion efficiency (PCE) of 4.24%, indicating that 9,10‐disubstituted PhA are potential donor materials for high‐efficiency BHJ PSCs.
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Adina Morozan Anca Dumitru Claudia Nastase Florin Nastase Ioan Stamatin 《Macromolecular Symposia》2008,267(1):129-133
Confidence in the potential of hydrogen as an energy vector and fuel bring the opportunities for enhancing electrolyzer performance. The aim of this paper is to develop new polymer nanocomposites as electrolyte membranes for PEM-electrolyzer. A series of nanocomposite membranes, including GEFC/TiO2, GEFC/CNTs, and GEFC/TiO2CNTs have been developed and characterized by FT-IR spectroscopy and AFM. The application of polymer nanocomposite membranes in electrochemical cells for water electrolysis was investigated. Experimental results obtained with respect to performance are reported and discussed related to GEFC membrane. 相似文献