Nothing on this shelf is chosen because someone liked the look of it. Every material here answers a requirement that the ordinary families cannot meet, and every one of them charges for it in machine capability, cost and failure rate.
The useful way to read the family is as a ladder, where each rung demands more of the printer than the one below.
| Material | Roughly needs | Chosen when |
|---|---|---|
| PC-ABS | 280 °C nozzle, hot bed, enclosure | a part must hold shape where ABS gives up, without polycarbonate's temperament |
| Polycarbonate | 310 °C nozzle, 120 °C bed, enclosure | clarity, impact and heat together |
| PPA | 320 °C nozzle, heated chamber, 100 °C dryer | sustained heat, typically under a bonnet |
| ULTEM 9085 | 390 °C nozzle, heated chamber | flame, smoke and toxicity certification |
| PEEK | 440 °C nozzle, hot chamber | continuous high temperature and aggressive chemicals |
The honest gate before you climb
Read the machine column first. It is the constraint that actually decides this, and no amount of tuning negotiates with it — hardware either reaches the temperature or it does not, and a box with a lid on it is not the same thing as a chamber with a heater in it.
This site's material selector takes a maximum nozzle temperature and an enclosure flag as inputs for exactly this reason. Telling it what your printer is capable of removes most of this shelf before you get attached to anything on it.
The second gate is whether the requirement is real. If the part never exceeds about 120 °C, a fibre-filled polyamide from the composites does the job on a machine that may already be in your workshop, at a fraction of the cost.
The outlier, named honestly
Polypropylene sits in this family and is not about temperature at all. It is here because it demands an enclosure and defeats every ordinary approach, but what it is chosen for is chemical inertness and fatigue life — the ability to be bent back and forth essentially forever without cracking. Nothing else on this site comes close on either count, and nothing else has to be printed onto its own packing tape because no build surface will hold it.
If you arrived at this shelf looking for heat, PP is not your material. If you arrived looking for a living hinge or a container that shrugs off solvents, it is the only entry that matters.
What the family shares
Warping that scales with capability. These polymers combine substantial shrinkage with high stiffness and high glass transitions, and a stiff material cannot relieve contraction stress by yielding gently — it stores it and releases it all at once. Chamber temperature, not bed temperature, is the lever.
Hydrolysis. Polycarbonate, the polyamides and the polyetherimide all suffer chain scission when printed damp, which is chemical damage rather than a surface flaw. Drying temperatures here range from 80 °C to 120 °C — above what a food dehydrator reaches for most of the shelf, which makes it an equipment requirement rather than a matter of diligence.
Failure rates that belong in the quote. A 5% allowance is realistic for PLA and fictional here. Prints on this shelf fail often enough that the failure term in a cost estimate frequently exceeds the electricity by a factor of five or more, and a quote that omits it loses money on the material where a failure is most expensive.
Post-processing difficulty. Chemical inertness is much of what you bought, and it defeats adhesives and paint just as effectively as it defeats solvents. Design mechanical joints.
Work down from the temperature
Work from the temperature the part must survive, then check it against your machine. Above 150 °C continuously, and with the budget for it, PEEK. Certification-driven, in aerospace or rail, ULTEM 9085. Sustained heat in a vehicle, PPA. Heat plus clarity plus impact, polycarbonate. Heat without polycarbonate's difficulty, PC-ABS.
And if the answer to "how hot" turns out to be "not very", you are on the wrong shelf, which is the most useful conclusion this page can offer.