Polyimide
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| Polyimide | |||||||||||||||||||||||||||
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| Density | 1430 kg/m3 | ||||||||||||||||||||||||||
| Young's modulus(E) | 3200 MPa | ||||||||||||||||||||||||||
Tensile strength(σt)</td>| 75-90 MPa | </tr>
Elongation @ break | 4-8% | notch test | 4-8 kJ/m2</td></tr>
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Glass temperature | >400°C | melting point | - | Vicat B | -C | heat transfer coefficient (λ) | 0.52 W/m.K | linear expansion coefficient (α) | 5.5 10-5 /K</td></tr>
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Specific heat (c) | 1.15 kJ/kg.K | Water absorption (ASTM) | 0.32 | Price | 15-25 €/kg | # ↑ Deformation temperature at 10kN needle load </th></tr>
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source: A.K. vam der Vegt & L.E. Govaert, Polymeren, </th></tr>
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van keten tot kunstof, ISBN 90-407-2388-5</th></tr>
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</table> Polyimide (sometimes abbreviated PI) is a polymer of imide monomers. The structure of imide is as shown below.  Line diagram of the linear polyimide monomer There are two general types of polyimides. One type, so called linear polyimides, are made by combining imides into long chains. Aromatic heterocyclic polyimides are the other usual kind, where R′ and R″ are two carbon atoms of an aromatic ring. Examples of polyimides include VTEC PI, Kapton, P84, Meldin, and Vespel. Polyimides have been in mass production since 1955. See also: Polyamide de:Polyimid |
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