PPA, at 140 to 250 °C of heat deflection. Then ULTEM 9085 at 150 to 175, PA6-CF at 120 to 190 and PA6-GF at 110 to 190.
The rankings on heat deflection are meaningless, though, until you check what your machine can extrude.
Your hotend is the real filter
Ask the same question with an enclosed machine limited to a 300 °C nozzle and two of the four disappear: ULTEM needs at least 350 °C and PEEK needs 380 °C. What remains is PPA, PA6-CF, PC-ABS and PA6-GF.
That is the honest shortlist for a well-equipped consumer printer, and PC-ABS is the one on it that most people can actually run — 250 to 280 °C nozzle, 100 to 115 °C bed, 95 to 120 °C of heat deflection.
Heat deflection is not melting point
The number is the temperature at which the polymer starts to deform under load. An unloaded part survives higher; a part carrying weight fails lower.
So a bracket rated to 100 °C is not a bracket you can trust at 95 °C with a motor hanging off it. Treat the figure as a ceiling to stay well below, not a target to approach.
The realistic middle ground
Most "it needs to survive some heat" problems are really "it must not sag in a car in summer", and that is a much lower bar:
- PLA at 52 to 60 °C fails it
- PETG at 68 to 80 °C passes comfortably and prints on any machine
- ABS or ASA at 88 to 105 °C passes with room to spare, at the cost of an enclosure
PETG is the answer to this question far more often than any material on the leaderboard.
Annealing as a shortcut
Heat-treating a PLA part raises its heat deflection substantially by increasing crystallinity. It also shrinks the part in X and Y and grows it in Z, so it works for brackets and not for fitted components.
Rank on heat resistance against your machine's real limits in the material selector.