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Polyetherimide (PEI; branded as Ultem[1]) is an amorphous, amber-to-transparent thermoplastic with characteristics similar to the related plastic PEEK. When comparing PEI to PEEK, the former is cheaper but has lower impact strength and a tighter temperature range.[2]
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| Names | |
|---|---|
| Other names
PEI, Ultem
| |
| Identifiers | |
| ChemSpider |
|
| ECHA InfoCard | 100.126.800 |
CompTox Dashboard (EPA)
|
|
| Properties | |
| (C37H24O6N2)n | |
| Molar mass | Variable |
| Appearance | Amber-to-transparent solid |
| Density | 1.27 g/cm3 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
| |
PEI plastics were first introduced into the market by General Electric (GE) in 1982 under the trade name Ultem.[3]
Due to its adhesive properties and chemical stability it became a popular bed material for FFF 3D printers.
Structure
editThe molecular formula of the PEI repeating unit is C37H24O6N2 and the molecular weight is 592.61 g/mol.[4] It contains phthalimide and bisphenol A sub-units.
Properties
editThe glass transition temperature of PEI is 217 °C (422 °F). Its amorphous density at 25 °C is 1.27 g/cm3(.046 lb/in³). It is prone to stress cracking in chlorinated solvents. Polyetherimide is able to resist high temperatures while maintaining stable electrical properties over a wide range of frequencies. This high strength material offers excellent chemical resistance and ductile properties suitable for various applications, even those involving steam exposure.[5]
References
edit- ^ "Ultem". Curbell Plastics. Retrieved 2 November 2023.
- ^ http://www.mcmaster.com/#ultem/=otzvqt Referenced Oct 7, 2013
- ^ "What Is Polyetherimide (PEI)?". Retrieved 2024-10-15.
- ^ Scott, Chris. "polyetherimide information and properties". www.polymerprocessing.com. Retrieved 2018-04-30.
- ^ "Injection Molding Material Selection Guide". www.abtecinc.com. Retrieved 2018-04-30.
