Electrospun Polymer Composite Membrane with Superior Thermal Stability and Excellent Chemical Resistance for High-Efficiency PM2.5 Capture

Abstract Polypropylene (PP) is one of the most used polymers for microporous membrane fabrication due to its good thermal stability, chemical resistance, mechanical strength, and low cost. There have been numerous studies reporting the developments and applications of PP membranes. However, PP membrane with high performance is still a challenge. Thus, this article presents a comprehensive overview of the advances in the preparation, modification and application of PP membrane. The preparation methods of PP membrane are firstly reviewed, followed by the modification approaches of PP membrane. The modifications includes hydrophilic and superhydrophobic modification so that the PP membranes become more suitable to be applied either in aqueous applications or in non-aqueous ones. The fouling resistant of hydrophilized PP membrane and the wetting resistant of superhydrophobized PP membrane are then reviewed. Finally, special attention is given to the various potential applications and industrial outlook of the PP membranes.

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Lithium garnet based free-standing solid polymer composite membrane for rechargeable lithium battery

Journal of Solid State Electrochemistry ◽

10.1007/s10008-018-4010-3 ◽

2018 ◽

Vol 22 (10) ◽

pp. 2989-2998 ◽

Cited By ~ 23

Author(s):

K. Karthik ◽

Ramaswamy Murugan

Keyword(s):

Polymer Composite ◽

Composite Membrane ◽

Lithium Battery ◽

Solid Polymer ◽

Free Standing ◽

Rechargeable Lithium Battery ◽

Lithium Garnet

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Proof-Of-Concept of a Thermal Barrier Coated Titanium Cooling Layer for an Inside-Out Ceramic Turbine

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4052021 ◽

2021 ◽

Author(s):

Antoine Gauvin-Verville ◽

Patrick K. Dubois ◽

Benoit Picard ◽

Alexandre Landry-Blais ◽

Jean-Sébastien Plante ◽

...

Keyword(s):

Polymer Composite ◽

Safety Factor ◽

Gas Turbines ◽

High Efficiency ◽

Cooling Power ◽

Thermal Barrier ◽

Inlet Temperature ◽

Turbine Stage ◽

Minimum Safety Factor ◽

Inside Out

Abstract Increasing turbine inlet temperature (TIT) of recuperated gas turbines would lead to simultaneously high efficiency and power density, making them prime candidates for low-emission aeronautics applications, such as hybrid-electric aircraft. The Inside-out Ceramic Turbine (ICT) architecture achieves high TIT by using compression-loaded monolithic ceramics. To resist inertial forces due to blade tip speed exceeding 450 m/s, the shroud of the ICT is made of carbon-polymer composite, wound around a metallic cooling ring. This paper demonstrates that it is beneficial to use a titanium alloy cooling ring with a thermal barrier coating (TBC), rather than nickel superalloys, for the interstitial cooling ring protecting the carbon-polymer from the hot combustion gases. A numerical Design of Experiments (DOE) analysis shows the design trade-offs between the minimum safety factor and the required cooling power for multiple geometries. An optimized high-pressure first turbine stage of a 500 kW microturbine concept using ceramic blades and a titanium cooling ring in an ICT configuration is presented. Its structural performance (minimum safety factor of 1.4) as well as its cooling losses (2% of turbine stage power) are evaluated. Finally, a 20 kW-scale prototype is tested at 300 m/s and a TIT of 1375 K during 4hrs to demonstrate the viability of the concept. Experiments show that the polymer composite was kept below its maximum safe operating temperature and components show no early signs of degradation.

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Isolation of Cellulose Nanofibers (CNFs) based on Ball-milling Technique Combined with Supercritical Carbon dioxide/ethanol Pretreatment

10.21203/rs.3.rs-277886/v1 ◽

2021 ◽

Author(s):

Zhijun Hu ◽

Xinyu Cao ◽

Guanhong Huang ◽

Daliang Guo

Keyword(s):

Thermal Stability ◽

Reaction Time ◽

Ball Milling ◽

High Efficiency ◽

Cellulose Nanofibers ◽

Sem Images ◽

Tempo Oxidation ◽

Good Thermal Stability ◽

Ethanol Pretreatment ◽

Ball Milling Technique

Abstract Here, a new pretreatment method has been developed to produce CNFs from micro-fibrillated cellulose (MFC) by supercritical CO 2 pretreatment followed with ball-milling (SCB). MFC was obtained from cotton stalk by chemical purification.Experimental factors were controlled to enhance the properties of SCB-CNF, meanwhile a comparative study was conducted with the method of TEMPO oxidation and microfluid homogenization (TMH). Compared to TMH-CNF, the SCB-CNF has such advantages as Energy saving, high efficiency and environmental protection, indicating a wide application in heat-resistant materials, load materials and other fields. The solid yields of P-MFC after supercritical CO 2 pretreatment gradually decreased together with the temperature and the reaction time. Scanning electron microscope (SEM) images of the SCB-CNF and TMH-CNF show that the morphology of the SCB-CNF was basically acicular but that of the TMH-CNF was mainly soft fibrous. The SCB-CNF is smaller in width and shorter in length, and its size is between CNC and CNF. Thermal gravimetric results suggest that the thermal stability of the SCB-CNF was substantially higher than those of the TMH-CNF. XRD results indicate that the crystallinity showed an initial increasing trend and then declined with increasing temperature and reaction time, and the crystallinity value of SCB-CNF was larger than that of CNFs. The smaller SCB-CNF became rougher and had a larger surface area. High crystallinity make good thermal stability, short and coarse fiber, easier to disperse than CNF, less energy consumption for dispersion, better than 3D mesh. It can be widely used in polymer composites, reinforcing agents, membrane materials and other fields.

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Effect of Heat Treatment on the Properties of Polyetheretherketone and its Composite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1167.23 ◽

2021 ◽

Vol 1167 ◽

pp. 23-33

Author(s):

Alaa A. Mohammed

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Thermal Stability ◽

Bioactive Glass ◽

Glass Powder ◽

Chemical Resistance ◽

Positive Influence ◽

Thermoplastic Polymer ◽

High Chemical ◽

High Chemical Resistance

Polyetheretherketone (PEEK) is a semicrystalline thermoplastic polymer with high chemical resistance, thermal stability and excellent mechanical properties. In the present work, neat PEEK and 3% bioactive glass/PEEK composites were annealed at various temperatures (100 °C, 200 °C and 300 °C) for (30 and 60) min and characterized with mechanical and density tests, differential scanning calorimetery and Fourier transform infrared spectroscopy. Results manifested bioactive glass powder enhanced the properties of the PEEK matrix. Thermal annealing at (200 and 300 °C) had a positive influence on the mechanical properties and density owing to increase in the level of crystallinity, whereas annealing at (100 °C) had not effect on the properties.

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