PPS-CF Filament Promises 240C Heat Resistance on Standard Desktop Printers

PPS-CF is having a moment. Polyphenylene sulfide reinforced with chopped carbon fiber has become the filament everyone asks about once they outgrow PETG-CF but are not ready to buy a PEEK-capable machine. A new video from My Tech Fun, published August 22, 2026, puts the material through a full test cycle and the results clarify exactly what PPS-CF can and cannot do on a standard desktop setup.

The Material in Plain Terms

PPS-CF is a 10% carbon-fiber-reinforced composite based on polyphenylene sulfide, the same polymer used in industrial chemical-plant piping and aerospace fluid-handling components. That background matters because it gives the filament a set of properties that no other commonly available desktop material can match: a heat deflection temperature around 242C, UL-94 V-0 flame rating, 0.05% water absorption, and a bending modulus above 7,000 MPa. Those numbers place it well above PETG-CF and PA12-CF on every thermal and chemical metric.

What the Video Tested

My Tech Fun ran the standard suite: dimensional accuracy across a range of part geometries, interlayer strength, creep resistance under sustained load, chemical resistance to common solvents, and a soldering-iron torture test to demonstrate the heat deflection behavior visually. The soldering-iron segment is the one people will quote: a PPS-CF part held its shape when touched with a hot iron where a PETG or PLA part would deform immediately.

The creep test is the more practically useful result for engineers. PPS-CF parts under sustained load at elevated temperature showed significantly less deformation over time than comparable PA12-CF parts, which is the comparison that matters for under-hood automotive brackets, jigs that sit in hot environments, and functional fixtures used near heated tooling.

The Practical Trade-offs

PPS-CF prints between 310C and 350C at the nozzle, requires a hardened steel or tungsten carbide nozzle, and performs best inside an actively heated chamber held at 60C to 65C. It also needs thorough drying before printing: 8 to 12 hours at 100C to 140C, and an active dryer throughout the print. Those requirements are achievable on several current desktop machines, including the Qidi Plus 4 and Bambu Lab X1 Carbon with modified settings, but they are not plug-and-play.

Post-processing adds another step. Annealing at 120C for at least 6 hours relieves residual print stress and locks in the full heat deflection rating. Without annealing, the part still works, but dimensional stability over thermal cycles degrades faster.

Where It Fits

PPS-CF makes sense when the design requirement is sustained heat above 200C, exposure to fuels or solvents, or a V-0 flame rating for enclosed electrical components. It is not a replacement for PET-CF when the priority is easy printability, or for PA12-CF when the part needs impact toughness at room temperature. Read the requirements, then choose the filament.