| PEEK | |
|---|---|
| Density | 1320 kg/m3 |
| Young's modulus (E) | 3.6 GPa |
| Tensile strength (σt) | 90-100 MPa |
| Elongation @ break | 50% |
| notch test | 55 kJ/m2 |
| Glass temperature | 143 °C |
| melting point | ~343 °C |
| Thermal Conductivity | 0.25 W/m.K |
| Water absorption, 24 hours (ASTM D 570) | - 0.1% |
| source:[1] | |
Polyether ether ketone (PEEK) is a colourless organic polymer thermoplastic used in engineering applications.
Contents |
PEEK polymers are obtained by step-growth polymerization by the dialkylation of bisphenolate salts. Typical is the reaction of 4,4'-difluorobenzophenone with the disodium salt of hydroquinone, which is generated in situ by deprotonation with sodium carbonate. The reaction is conducted around 300 °C in polar aprotic solvents - such as diphenylsulphone.[2][3]
PEEK is a semicrystalline thermoplastic with excellent mechanical and chemical resistance properties that are retained to high temperatures. The Young's modulus is 3.6 GPa and its tensile strength 90 to 100 MPa.[4] PEEK has a glass transition temperature at around 143 °C (289 °F) and melts around 343 °C (662 °F). It is highly resistant to thermal degradation as well as attack by both organic and aqueous environments. It is attacked by halogens and strong Bronsted and Lewis acids as well as some halogenated compounds and aromatic hydrocarbons at high temperatures.
Because of its robustness, PEEK is used to fabricate items used in demanding applications, including bearings, piston parts, pumps, compressor plate valves, and cable insulation. It is one of the few plastics compatible with ultra-high vacuum applications. PEEK is considered an advanced biomaterial used in medical implants. It is extensively used in the aerospace, automotive, teletronic, and chemical process industries. PEEK's mechanical properties at elevated temperatures have led to it being used in at least two varieties of Reprap extruder as thermal insulation. This means the rest of the extruder structure can be made of the same material as the object being fabricated without self-destruction.
PEEK is not traditionally a shape memory polymer, however, recent advances in processing have allowed shape memory behavior in PEEK with mechanical activation. This technology has expanded to applications in orthopedic surgery.[5]