PBI Fiber (Celazole) PBI-FELT
Grade
also Celazole
Nonwoven form for hot-gas filtration, aluminium-casting contact rolls and thermal insulation batts above 250 °C.
Values for the PBI-FELT condition
Other PBI Fiber (Celazole) grades and fills
PBI Fiber (Celazole) is listed in 6 conditions; see the grade overview at PBI Fiber (Celazole).
Compare all 6 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
PBI-FELTThis page PBI needle-punched felt / blended filter media | Nonwoven form for hot-gas filtration, aluminium-casting contact rolls and thermal insulation batts above 250 °C. | — | 12 | 35 | — |
PBI continuous filament yarn | Continuous filament form for woven high-temperature tapes, sewing thread and reinforcement scrims. | — | 380 | 25 | — |
three-fiber PBI/aramid blend, cost-optimised outer shell | Entry-level PBI-containing turnout shell where budget matters and full PBI Gold performance is not required. | — | 1,000 | 9 | — |
PBI-rich blend for maximum thermal protective performance | Higher PBI fraction than PBI Gold; pick for the highest char integrity and lowest shrinkage in flashover exposure. | — | 1,100 | 10 | — |
PBI Gold | Classic firefighter turnout outer-shell blend: PBI supplies char stability and no shrink, para-aramid supplies tear and tensile strength. | — | 1,300 | 8 | — |
PBI/para-aramid blend with high-tenacity aramid ripstop grid | Choose when a lighter outer shell with much higher tear strength is required for structural firefighting gear. | — | 1,500 | 7 | — |
What is PBI Fiber (Celazole) PBI-FELT?
PBI Fiber (Celazole) PBI-FELT is PBI Fiber (Celazole) in the PBI-FELT grade — nonwoven form for hot-gas filtration, aluminium-casting contact rolls and thermal insulation batts above 250 °C. PBI Fiber (Celazole) PBI-FELT has a tensile strength of 12 MPa (1.74 ksi), weaker than 84% of composite grades. Elongation at break is 35% and the elastic modulus is 0.15 GPa (0.0218 Msi). PBI Fiber (Celazole) PBI-FELT has a density of 1.43 g/cm³ (0.0517 lb/in³), lighter than 63% of composite grades. Its glass-transition temperature is 427°C (801 °F).
Advantages
- Ductile — tolerates forming and impact — 35%, better than 101% of composite grades
Limitations
- Absorbs moisture — dry before molding — 13%, worse than 100% of composite grades
- Low stiffness — 0.15 GPa (0.0218 Msi), worse than 90% of composite grades
- Poor heat conductor — 0.05 W/m·K (0.0289 BTU/hr·ft·°F), worse than 87% of composite grades
- High embodied carbon — 28 kg CO₂/kg, worse than 76% of composite grades
PBI Fiber (Celazole) PBI-FELT properties
Typical room-temperature values for PBI Fiber (Celazole) PBI-FELT; 12 are specific to this condition. Other listed values are PBI Fiber (Celazole) reference data and may not represent this condition. Bars are the position among composite grades.
Physical4
PBI Fiber (Celazole) PBI-FELT has a density of 1.43 g/cm³ (0.0517 lb/in³), lighter than 63% of composite grades. Its glass-transition temperature is 427°C (801 °F).
Mechanical3
PBI Fiber (Celazole) PBI-FELT has a tensile strength of 12 MPa (1.74 ksi), weaker than 84% of composite grades. Elongation at break is 35% and the elastic modulus is 0.15 GPa (0.0218 Msi).
Thermal8
PBI Fiber (Celazole) PBI-FELT is rated for continuous service to 300°C (572 °F). It conducts heat at 0.05 W/m·K (0.0289 BTU/hr·ft·°F), worse than 87% of composite grades. Thermal expansion is 23 µm/m·K (12.8 µin/in·°F).
Electrical3
PBI Fiber (Celazole) PBI-FELT has an electrical resistivity of 1×10¹² Ω·m.
Chemical & Environmental2
UV resistance is poor.
Sustainability3
Producing a kilogram of PBI Fiber (Celazole) PBI-FELT takes about 450 MJ of energy and emits 28 kg of CO₂ — more than 79% of composite grades. Typical recycled content is 0%.
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with PBI Fiber (Celazole) PBI-FELT
Is PBI Fiber (Celazole) easy to machine?
Not machined as a fiber; cut with hot knife or ultrasonic cutter, dry-cut felts blunt steel blades quickly.
Can PBI Fiber (Celazole) be welded?
Not weldable — PBI does not melt; joins are sewn (PBI or aramid thread) or mechanically clamped.
Can PBI Fiber (Celazole) be formed, bent or molded?
Processed on conventional cotton/aramid staple spinning and needle-punch lines; blend with para-aramid to raise yarn strength and reduce cost.
What surface finishes work on PBI Fiber (Celazole)?
Natural gold colour is inherent and essentially undyeable by conventional means; scour to remove spin finish and pre-shrink at 250–300 °C before laminating or coating.
PBI Fiber (Celazole) chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| spin finish / processing lubricantremovable surface finish on staple and filament | 0.2 – 1 | 0.5 |
| poly[2,2'-(m-phenylene)-5,5'-bibenzimidacondensation product of 3,3'-diaminobenzidine and diphenyl isophthalate; fiber is sulfonation-stabilised | ≥ 99 (balance) | — |
PBI Fiber (Celazole) PBI-FELT — frequently asked
What is PBI Fiber (Celazole) PBI-FELT used for?
PBI Fiber (Celazole) PBI-FELT is typically used for firefighter turnout gear, aerospace fire-blocking layers and high-temperature protective clothing. In short: highest-temperature organic fiber; non-melting, char-forming; blended with para-aramid.
What is the tensile strength of PBI Fiber (Celazole) PBI-FELT?
PBI Fiber (Celazole) PBI-FELT has a typical tensile strength of 12 MPa (1.74 ksi) — weaker than 84% of composite grades. Strength varies by condition: see the 6 listed tempers.
Is PBI Fiber (Celazole) PBI-FELT easy to machine?
Not machined as a fiber; cut with hot knife or ultrasonic cutter, dry-cut felts blunt steel blades quickly.
Can PBI Fiber (Celazole) PBI-FELT be welded?
Not weldable — PBI does not melt; joins are sewn (PBI or aramid thread) or mechanically clamped.
What surface finishes work on PBI Fiber (Celazole) PBI-FELT?
Natural gold colour is inherent and essentially undyeable by conventional means; scour to remove spin finish and pre-shrink at 250–300 °C before laminating or coating.
Can PBI Fiber (Celazole) PBI-FELT be formed, bent or molded?
Processed on conventional cotton/aramid staple spinning and needle-punch lines; blend with para-aramid to raise yarn strength and reduce cost.
What is the maximum service temperature of PBI Fiber (Celazole) PBI-FELT?
PBI Fiber (Celazole) PBI-FELT is rated for continuous use to about 300°C (572 °F), and briefly to 500°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- PBI Fiber and PBI Gold Fabric Technical Data — PBI Performance Products, Inc. (2023)
- Celazole PBI Polymer Property Data — Celanese / PBI Performance Products (2022)
- Handbook of Fiber Chemistry — High-Performance Fibers — CRC Press (2007)
- Engineered Materials Handbook Vol.2: Engineering Plastics — ASM International (1988)
- NFPA 1971 Standard on Protective Ensembles for Structural Fire Fighting — NFPA (2018)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.