| PEEK | |
|---|---|
| Density | 1300 kg/m3 |
| Young's modulus(E) | 3700 MPa |
| Tensile strength(σt) | 90 MPa |
| Elongation @ break | 50% |
| notch test | 55 kJ/m2 |
| Glass temperature | 143°C |
| melting point | 334°C |
| Vicat B<sup class="plainlinks nourlexpansion citation" id="ref_<1>">[1] | - |
| heat transfer coefficient (λ) | 0.25 W/m.K |
| linear expansion coefficient (α) | 1.7 10-5 /K |
| Specific heat (c) | - kJ/kg.K |
| Water absorption (ASTM) | - |
| Price | 25-50 €/kg |
| # <span class="citation wikicite" id="endnote_<vic>">^ Deformation temperature at 10kN needle load | |
| source: A.K. vam der Vegt & L.E. Govaert, Polymeren, | |
| van keten tot kunstof, ISBN 90-407-2388-5 | |
Polyetheretherketones (PEEK), also referred to as polyketones, are obtained from aromatic dihalides and bisphenolate salts by nucleophilic substitution. The bisphenolate salt is formed in situ from bisphenol and either added sodium or added alkali metal carbonate or hydroxide.
PEEK is partially crystalline, and has a glass transition temperature of 143 °C and a melting temperature of 334 °C. The material is resistant to both organic and aqueous environments, and is used in bearings, piston parts, pumps, compressor plate valves, and cable insulation applications.
PEEK is a thermoplastic with extraordinary mechanical properties. The Young's Modulus is 3.6 GPa and its tensile strength 170 MPa.
PEEK also exhibits good chemical resistance in many environments, including alkalis (i.e. sodium, potassium and ammonium hydroxides) , aromatic hydrocarbons, alcohols (i.e. ethanol, propanol), greases, oils and halegonated hydrocarbons.
However, it's performance in acids is very dependent on the type of acid - PEEK shows poor resistance in oleum and concentrated sulphiric, nitric, hydrochloric, hydrobromic and other mineral acids. It's resistance to hydrofluoric acid is very poor. PEEK shows good resistance to phosphoric acid and organic acids (acetic, citric, oxalic, tataric etc.), but varying resistance in the presence of halogens. PEEK is resistant to dissolution by some formaldehydes and ketones such as acetone, but not (at higher temperature) methylethyl ketone.
PEEK is also considered an advanced biomaterial used in medical implants.