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FEP; CAS Registry Number: 25067-11-2 Density [1] 2150 kg/m 3: Flexural modulus(E) 586 M Pa: Tensile strength(t) 23 M Pa: Elongation @ break 325% Folding endurance Varies Notch test Melting point: 260 °C Maximum operating temperature 204 °C Water absorption (ASTM) <0.01 % after 24 hours Dielectric constant (Dk) at 1M Hz: 2.1 Dissipation factor
When melting points of the monomers are sufficiently low, a polyester can be formed via direct esterification while removing the reaction water via vacuum. Direct bulk polyesterification at high temperatures (150 – 290 °C) is well-suited and used on the industrial scale for the production of aliphatic, unsaturated, and aromatic–aliphatic ...
PTFE is a thermoplastic polymer, which is a white solid at room temperature, with a density of about 2200 kg/m 3 and a melting point of 600 K (327 °C; 620 °F). [26] It maintains high strength, toughness and self-lubrication at low temperatures down to 5 K (−268.2 °C; −450.7 °F), and good flexibility at temperatures above 194 K (−79.15 ...
Polyester resins are synthetic resins formed by the reaction of dibasic organic acids and polyhydric alcohols. Maleic anhydride is a commonly used raw material with diacid functionality in unsaturated polyester resins. [1] Unsaturated polyester resins are used in sheet moulding compound, bulk moulding compound and the toner of laser printers.
If the residence time and/or melt temperature (temperature at melting) are too high, then thermal degradation or thermooxidative degradation will occur resulting in discoloration and reduced molecular weight, as well as the formation of acetaldehyde, and the formation "gel" or "fish-eye" formations through cross-linking.
In polymers, such as plastics, thermal degradation refers to a type of polymer degradation where damaging chemical changes take place at elevated temperatures, without the simultaneous involvement of other compounds such as oxygen. [1] [2] Simply put, even in the absence of air, polymers will begin to degrade if heated high enough. It is ...
The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends on pressure and is usually specified at a standard pressure such as 1 atmosphere or 100 kPa.
They can be either thermoplastic or elastomeric materials, [citation needed] with melting points ranging from 40 to 180 °C. [ citation needed ] The mechanical properties and biocompatibility of PHA can also be changed by blending, modifying the surface or combining PHA with other polymers, enzymes and inorganic materials, making it possible ...