Properties at high temperature

Polysulfone Good transparency, high mechanical properties, heat resistance, electrical properties at high temperature, can be electroplated Injection molding... 

Diamantane-based polymers are synthesized to take advantage of their stiffness, chemical and thermal stability, high glass transition temperature, improved solubility in organic solvents, and retention of their physical properties at high temperatures. All these special properties result from their diamantane-based molecular structure [90]. Polyamides are high-temperature polymers with a broad range of applications in different scientific and industrial fields. However, their process is very difficult because of poor solubility and lack of adequate thermal stability retention [90]. Incorporation of 1,6- or... 

Silicone rubbers exhibit good resistance to heat ageing, and are considered to be usable up to temperatures of 200 °C. Although silicones do not exhibit high strength at room temperature, they do retain their properties at high temperatures to a much greater extent than other rubbers. 

So, if these hybrid homopolymers exhibit interesting properties at high temperatures, their properties at low temperatures are poorer than those of the classical polysiloxanes, which is why we decided to study fluorinated hybrid polysiloxanes containing the telomers prepared above. 

Poly(tetrafluoroethylene) (PTFE), which is also known by DuPont s trade-name Teflon, is a solid at room temperature and has a dielectric constant in the range of 2.00-2.08, while its monomer, tetrafluoroethylene, is a gas at room temperature. PTFE is exceptionally chemically inert, has excellent electrical properties and outstanding stability, and retains its mechanical properties at high temperatures. The problem with PTFE is that it is not processable. A family of commercial polymeric materials known as Teflon AF is believed to be a... 

The combination of thermal stability and dielectric performance makes PEN an attractive electrical insulator in electrical motors. Motors with high operating temperatures, such as hermetically sealed refrigerator motors and business machines, need films that are resistant to shrinking and retain nonconducting properties at high temperatures. 

Hydroxy-terminated polybutadiene (HTPB) is considered to be the best binder for obtaining high combustion performance, superior elongation properties at low temperatures, and superior mechanical strength properties at high temperatures. This combination of properties is difficult to achieve in double-base propellants. HTPB is characterized by terminal -OH groups on a butadiene polymer. The other type of butadiene polymer used is carboxy-terminated polybutadiene (CTPB), which is cured with an imine or an epoxy resin. It should be noted that CTPB is somewhat sensitive to humidity, which has an adverse effect on its ageing charac-... 

Ceramic matrix composites are expected to be applied to structural materials for fusion reactors because of their excellent mechanical properties at high temperature and their... 

Chupka, W. A., D. J. Meschi, and J. Berkowitz, paper presented at the Symposium on Chemical and Thermodynamic Properties at High Temperatures at the International Congress of Pure and Applied Chemistry, Montreal, Canada, August 1961. 

Separators in lithium ion batteries must separate positive electrodes and negative electrodes to prevent short circuits, and must allow passage of electrolytes or ions. Porous films and nonwoven fabrics of resins are known separators. The lithium ion battery separators are also required to exhibit stable properties at high temperatures such as in charging, and therefore high heat resistance is desired (21). 

For proper estimation of a material, especially when it has engineering application, it is often necessary to know the strength properties at high temperatures which develop in the contact region during abrasion, cutting,... 

Polyarylates have good optical properties. Luminous light transmission can range from 84% to 88% with only 1% to 2% haze. Refractive index is 1.61. An important feature of the polyarylale family is high heat resistance demonstrated by a 34C°F (171°C) heat deflection temperature at 264 psi (1.8 mPa). The material exhibits good retention of properties at high temperature exposures 270,000 psi (1380 mPa) at 300 F (149°C) and over 200,000 psi at 350°F (177°C). 

The introduction of fluorine into the elastomeric macromolecule generally produces materials exhibiting an improved retention of properties at high temperatures, an improved flexibility at low temperatures, and an improved resistance to solvents. Essentially, there are two groups of fluoroelastomers fluoro-inorganic elastomers and fluorocarbon (or fluorohydrocarbon) elastomers. 

Thus, even if their properties at high temperatures are still very good, this is not so at low temperatures because of their high Tg or their high crystallinity. However, the polyethers for which the C —O—C bands bring free spinning and decrease the hardness of the perhalogenated —C—C sequence are exceptions. These are the Fomblin polyethers from Montefluos and the Krytox ones from Du Pont De Nemours. However, for these products, problems of solubility and reactivity are observed. 

The epoxy product cured with BF3-MEA is densely crosslinked and has excellent physical properties at high temperatures (150 to 175°C). When reacted with an unmodified epoxy resin, the resulting product is very hard and brittle. The chemical resistance, however, is only fair and somewhat less than that of epoxies that are cured with aliphatic amines. 

These PEI plastics show good physical and electrical properties at high temperatures and a 20,000 h service life at 230C (446F). Their thermal-oxidative stabilities are described as being less than the best polyimides, but better than the aromatic polyesters. 

K. Xia and T. G. Langdon, The Mechanical Properties at High Temperatures of SiC Whisker-Reinforced Alumina, in High Temperature/High Performance Composites, Materials Research Society Symposium Proceedings, Vol. 120, eds. F. D. Lemkey, S. G. Fishman, A. G. Evans, and J. R. Strife, Materials Research Society, Pittsburgh, PA, 1988, pp. 265-271. 

Navarrini [5] prepared tetrafluoroethylene/fluorovinyl ether co- and terpo-lymers, (IV), and (V), respectively, that behaved as both plastomers having good thermal and mechanical properties at high temperatures and elastomers with improved properties at low temperatures. Tetrafluoroethylene and non-fluorinated vinyl ether co- and terpolymers were also prepared in the investigation. 

The United States has to import all the cobalt it uses. One of the most important applications of cobalt is in the production of superalloys. These superalloys consist primarily of iron, cobalt, or nickel, with small amounts of other metals, such as chromium, tungsten, aluminum, and titanium. Superalloys are resistant to corrosion (rusting) and retain their properties at high temperatures. Superalloys are used in jet engine parts and gas turbines. 

Superalloys Consist primarily of iron, cobalt, or nickel, with small amounts of other metals that are resistant to corrosion (rusting) and retain their properties at high temperatures. 

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