High-temperature 3D Printing can be challenging. Filament materials like PEEK, PEI, PAEK, and PEK can be confusing. Vision Miner company specializes in PEEK and PEI, but let’s look at the differences between each.
PEEK (Polyether Ether Ketone) is new substance for industrial 3D-printing, created in 1926 by Imperial Chemical Industries (ICI). This UK manufacturer formulated Victrex, known today as PEEK. However, Victrex is now the name of an ICI spin-off company manufacturing PEEK. 
Like all chemicals, PEEK and other PAEK materials consist of specific building blocks of elemental molecules. The different names indicate the quantity/order of Ether and Ketone components.
PEEK is a Poly (multiple/blend) of Ether-Ether-Ketone (2 Ethers, 1 Ketone). PEKK is a different Poly: Ether-Ketone-Ketone (1 Ether, 2 Ketones). These building blocks change each substance overall. (In the same way that changing the ratio of liquids in a drink changes what drink it is.)
One common alternative to PEEK is PEI, generally a grade of SABIC's ULTEM™ resin, a derivative of Polyetherimide (PEI). While both materials have similar high-temperature resistance, they’re in different thermoplastic families.
PAEK’s plastic family is diverse, but PEIs lack a ketone in molecular structure. PEI was formulated by GE’s Plastics Division and purchased for use by SABIC in 2007. It has no major family members aside from PEI and PEI variants, which are generally less expensive, lower in impact strength, and lower in usable temperature.
Many thermoplastic names and types can be compared to Coca-Cola® sodas. Consider the original flavor as a basic formula. Then Coca-Cola® created variations, like Vanilla Coke, Diet Coke, Coke Zero, and Coke Life. Now, imagine if the original Coca-Cola® formula was free, to be manufactured by any company, worldwide. Now imagine each company creating their own flavor. This is similar to how PAEK or PEI substances developed in the chemicals world.
Victrex created a brand new plastic “flavor” known as PEEK in the 1980s. It took off as a machinable thermoplastic. Then other companies wanted to develop their own PEEK “flavor.” So Victrex PEEK became the original “flavor” in the PEEK family, which now includes DowDuPont’s PEEK (Vespel) , Quadrant’s PEEK (Ketron), and SABIC’s PEEK (LUBRICOMP).
The world of high-temperature thermoplastics is quite diverse. Many options range from PAEKs like PEEK and PEKK to grade variants of PEI, and each choice brings a trade-off. When companies make new products, they must research and consider the material properties they want, for what they will manufacture. Thermoplastics can be costly and should match the need.
ULTEM™ resin created by SABIC is a trademark of SABIC or it's affiliates or subsidiaries.
