scholarly journals Functionalized copolyimide membranes for the separation of gaseous and liquid mixtures

2010 ◽  
Vol 6 ◽  
pp. 789-800 ◽  
Author(s):  
Nadine Schmeling ◽  
Roman Konietzny ◽  
Daniel Sieffert ◽  
Patrick Rölling ◽  
Claudia Staudt
Keyword(s):  
Chemical Resistance ◽  
Temperature Stability ◽  
Liquid Mixtures ◽  
Industrial Applications ◽  
Gas Separations ◽  
High Temperature Stability ◽  
Good Separation ◽  
Separation Processes ◽  
Membrane Materials ◽  
Sulfur Containing

Functionalized copolyimides continue to attract much attention as membrane materials because they can fulfill the demands for industrial applications. Thus not only good separation characteristics but also high temperature stability and chemical resistance are required. Furthermore, it is very important that membrane materials are resistant to plasticization since it has been shown that this phenomenon leads to a significant increase in permeability with a dramatic loss in selectivity. Plasticization effects occur with most polymer membranes at high CO2 concentrations and pressures, respectively. Plasticization effects are also observed with higher hydrocarbons such as propylene, propane, aromatics or sulfur containing aromatics. Unfortunately, these components are present in mixtures of high commercial relevance and can be separated economically by single membrane units or hybrid processes where conventional separation units are combined with membrane-based processes. In this paper the advantages of carboxy group containing 6FDA (4,4′-hexafluoroisopropylidene diphthalic anhydride) -copolyimides are discussed based on the experimental results for non cross-linked, ionically and covalently cross-linked membrane materials with respect to the separation of olefins/paraffins, e.g. propylene/propane, aromatic/aliphatic separation e.g. benzene/cyclohexane as well as high pressure gas separations, e.g. CO2/CH4 mixtures. In addition, opportunities for implementing the membrane units in conventional separation processes are discussed.

A simply prepared flexible SiBOC ultrafine fiber mat with enhanced high-temperature stability and chemical resistance

RSC Advances ◽  
2015 ◽  
Vol 5 (80) ◽  
pp. 64911-64917 ◽  
Author(s):  
Song Xie ◽  
Yingde Wang ◽  
Yongpeng Lei ◽  
Bing Wang ◽  
Nan Wu ◽  
...  
Keyword(s):  
High Temperature ◽  
Chemical Resistance ◽  
Temperature Stability ◽  
High Temperature Stability ◽  
Ultrafine Fiber

A simply prepared flexible SiBOC ultrafine fiber mat with high-temperature stability and chemical resistance. I: A typical SiBOC material composed of Si, B, O and C. II: A comparison of SiBOC fibers and SiOC fibers treated under different conditions.

The Catalytic Synthesis of Inorganic Polymers for High Temperature Applications and as Ceramic Precursors

1989 ◽  
Vol 171 ◽  
Author(s):  
Jeffrey A. Rahn ◽  
Richard M. Laine ◽  
Zhi-Fan Zhang
Keyword(s):  
High Temperature ◽  
Glass Fibers ◽  
Temperature Stability ◽  
Industrial Applications ◽  
Catalyst Precursor ◽  
Inorganic Polymers ◽  
High Temperature Stability ◽  
Nmr Studies ◽  
Black Glass ◽  
Ceramic Precursors

AbsractPolysilsesquioxanes,-[RSi(O)1.5 ]x-, exhibit many properties that are potentially quite useful for industrial applications. These properties include high temperature stability (−600°C in O2); good adhesion and, liquid crystal-like behavior for some derivatives. Moreover, [MeSi(O)l.5]x, polymethylsilsesquioxane has been used successfully as a precursor for the fabrication of carbon fiber/“black glass” (SiO2/SiC/C) composites and “black glass” fibers.Current methods of preparation depend on hydrolysis of RSiCl3 or RSi(OR)3. Unfortunately, this approach leads to several products that are difficult to purify because polysilsesquioxanes exhibit a great propensity for forming gels. We describe here a simple catalytic approach to the synthesis of polymethylsilsesquioxane copolymers of the type -[MeRSiO].3[MeSi(O)1.5].7- where R - H, OMe, OEt, OnPr and OnBu. The R - H copolymer is produced by catalytic redistribution of -[MeHSiO]xoligomers using dimethyltitanocene, Cp2TiMe2 as the catalyst precursor.Following catalytic redistribution, the resulting copolymer, -[MeHSiO].3[MeSi(O)1.5].7−, is reacted in situ with alcohols to produce -[Me(R'O)SiO].3[MeSi(0)1.5].7− (where R' - Me, Et, nPr and nBu) which serve as masked forms of the polymethylsilsesquioxane. These new copolymers have been characterized by 1H, 13C and 29Si NMR TGA and DTA. The NMR studies allow us to assign structures for the copolymer.These new copolymers exhibit improved tractability. Their high temperature properties are all quite similar; although, the MeO-, EtO- and especially the nPrO- derivatives give much higher ceramic yields than expected.

scholarly journals Effects of a Reactive Phosphorus–Sulfur Containing Flame-Retardant Monomer on the Flame Retardancy and Thermal and Mechanical Properties of Unsaturated Polyester Resin

Polymers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1441 ◽  
Author(s):  
Kang Dai ◽  
Zhenzhen Deng ◽  
Guyue Liu ◽  
Yutong Wu ◽  
Wenbin Xu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Fourier Transform ◽  
High Temperature ◽  
Polyester Resin ◽  
Unsaturated Polyester ◽  
Temperature Stability ◽  
Thermal And Mechanical Properties ◽  
High Temperature Stability ◽  
Reactive Phosphorus ◽  
Sulfur Containing

A novel reactive phosphorus and sulfur-containing monomer (bis(acryloxyethyldiphenylphosphate)sulfone, BADPS) was synthesized to enhance the comprehensive performance of unsaturated polyester resin (UPR), and corresponding flame-retardant unsaturated polyester resins (FR-UPRs) with various amounts of BADPS were prepared by radical bulk polymerization. The flame retardancy and thermal and mechanical properties of the UPR samples were investigated by limiting oxygen index (LOI) measurements, cone calorimetry, differential scanning calorimetry (DSC), a thermogravimetric analysis (TGA), and a tension test. The results showed that the introduction of BADPS remarkably enhanced the flame resistance and high-temperature stability, as well as the tensile performance of UPR. Scanning electron microscopy (SEM), Fourier transform infrared (FTIR), and Raman spectroscopy studies revealed that BADPS can efficaciously promote the formation of UPR char residue with an improved microstructure and increased graphitization degree, which enhancedthe high-temperature stability and char yield of UPR. Additionally, a thermogravimetry-Fourier transform infrared (TG-FTIR) analysis corroborated that the evolution of combustible volatiles from UPR decomposition was substantially restrained by the incorporation of BADPS, which is beneficial for the suppression of fire hazards in UPR.

UNS N06455

Alloy Digest ◽  
1989 ◽  
Vol 38 (1) ◽  
Keyword(s):  
Corrosion Resistance ◽  
High Temperature ◽  
Stress Corrosion Cracking ◽  
Temperature Stability ◽  
Heat Treating ◽  
High Ductility ◽  
High Temperature Stability ◽  
Nickel Chromium ◽  
Long Time ◽  
Resistance To Stress

Abstract UNS NO6455 is a nickel-chromium-molybdenum alloy with outstanding high-temperature stability as shown by high ductility and corrosion resistance even after long-time aging in the range 1200-1900 F. The alloy also has excellent resistance to stress-corrosion cracking and to oxidizing atmospheres up to 1900 F. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Ni-367. Producer or source: Nickel and nickel alloy producers.

UNS R54620

Alloy Digest ◽  
1987 ◽  
Vol 36 (7) ◽  
Keyword(s):  
Titanium Alloy ◽  
High Temperature ◽  
Time Use ◽  
Temperature Stability ◽  
High Strength ◽  
Heat Treating ◽  
High Temperature Stability ◽  
Beta Titanium Alloy ◽  
Beta Titanium ◽  
Long Time

Abstract UNS No. R54620 is an alpha-beta titanium alloy. It has an excellent combination of tensile strength, creep strength, toughness and high-temperature stability that makes it suitable for service to 1050 F. It is recommended for use where high strength is required. It has outstanding advantages for long-time use at temperatures to 800 F. This datasheet provides information on composition, physical properties, elasticity, tensile properties, and bend strength as well as creep. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Ti-86. Producer or source: Titanium alloy mills.

Comparative Assessment of Sporophyte and Gametophyte Thermal Resistance of Winter Rape

2019 ◽  
pp. 15-22
Keyword(s):  
Elevated Temperatures ◽  
Rapid Assessment ◽  
Temperature Stability ◽  
Temperature Factor ◽  
Plant Genome ◽  
Limiting Factors ◽  
Initial Assessment ◽  
High Temperature Stability ◽  
Winter Rape ◽  
High Yields

The temperature factor is one of the limiting factors for obtaining high yields of crops, so one of the main tasks of selection is to search for temperature-resistant genotypes and to create on their basis the banks of crops with high temperature stability. The first step to solving this problem is to conduct a rapid assessment of the temperature plasticity of large populations and to isolate breeding-valuable genotypes from them. There are numerous methods that allow, in the short term with minimal technical and material costs, to carry out an initial assessment of a large number of genotypes at sporophytic level and differentiate them by resistance to the temperature factor. These methods include the method of estimating pollen populations. These studies have repeatedly been conducted on many cultures, their correctness is due to the expression of a large part of the plant genome, both at the diploid and haploid levels of development and demonstrated by many studies in this direction. The aim of our study was to study the stability of gametophyte and sporophyte of collecting varieties and varieties of winter rape to elevated temperatures, to study the correlation between the heat resistance of sporophyte and gametophyte.

Oxa-Michael polyaddition of vinylsulfonylethanol for aliphatic polyethersulfones

2021 ◽  
Author(s):  
Nicole Ziegenbalg ◽  
Ruth Lohwasser ◽  
Giovanni D’Andola ◽  
Torben Adermann ◽  
Johannes Christopher Brendel
Keyword(s):  
Refractive Index ◽  
High Temperature ◽  
Flame Retardant ◽  
Chemical Resistance ◽  
High Refractive Index ◽  
Industrial Applications ◽  
Interesting Class ◽  
The Common ◽  
Flame Retardant Properties

Polyethersulfones are an interesting class of polymers for industrial applications due to their unusual properties such as a high refractive index, flame-retardant properties, high temperature and chemical resistance. The common...

scholarly journals Progress and perspectives in dielectric energy storage ceramics

2021 ◽  
Vol 10 (4) ◽  
pp. 675-703
Author(s):  
Dongxu Li ◽  
Xiaojun Zeng ◽  
Zhipeng Li ◽  
Zong-Yang Shen ◽  
Hua Hao ◽  
...  
Keyword(s):  
Energy Storage ◽  
Power Systems ◽  
Temperature Stability ◽  
Pulse Power ◽  
Research Progress ◽  
High Temperature Stability ◽  
Dielectric Ceramic ◽  
Microstructural Design ◽  
Pulse Power Systems ◽  
Fatigue Endurance

AbstractDielectric ceramic capacitors, with the advantages of high power density, fast charge-discharge capability, excellent fatigue endurance, and good high temperature stability, have been acknowledged to be promising candidates for solid-state pulse power systems. This review investigates the energy storage performances of linear dielectric, relaxor ferroelectric, and antiferroelectric from the viewpoint of chemical modification, macro/microstructural design, and electrical property optimization. Research progress of ceramic bulks and films for Pb-based and/or Pb-free systems is summarized. Finally, we propose the perspectives on the development of energy storage ceramics for pulse power capacitors in the future.

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