Pre-oxidized Fiber Powder: High-Performance Filler for Heat-Resistant and Flame-Retardant Applications
Pre-oxidized fiber powder is a micron-sized organic material derived from polyacrylonitrile (PAN)-based pre-oxidized fibers. This powder is designed for use in high-temperature and flame-retardant applications, offering excellent thermal stability, conductivity, and chemical resistance.
What is Pre-oxidized Fiber Powder?
Produced through oxidative stabilization and grinding of PAN fibers, this powder has no melting point, is inherently flame-resistant, and exhibits a dark brown appearance. It expands the application scope of pre-oxidized fibers beyond traditional fiber uses.
Pre-oxidized Fiber Powder Manufacturing Process
- Fiber Stabilization: PAN precursor is oxidized at 200–300°C to form heat-resistant ladder polymers.
- Mechanical Milling: The stabilized fibers are ground using ball or jet milling to achieve desired particle sizes (1–100 μm).
- Surface Modification: The powder may undergo surface treatment to enhance resin compatibility and dispersion.
Pre-oxidized Fiber Powder Key Properties
- Withstands long-term temperatures of 300°C+, short-term up to 500°C
- LOI ≥ 45%, classified as a non-flammable material
- Adjustable electrical resistivity: 10²–10⁶ Ω·cm
- Resistant to acids, alkalis, and solvents
- Lightweight: 1.4–1.6 g/cm³
- Non-toxic and RoHS compliant
Pre-oxidized Fiber Powder Key Technical Parameters
| Parameter | Specification | Test Standard |
|---|---|---|
| Particle Size (D50) | 10-50 μm (customizable) | ISO 13320 (Laser diffraction) |
| Carbon Content | 50%-65% | GB/T 3521 (High-temperature combustion) |
| Ash Content | ≤ 5% | GB/T 20020 |
| Volatile Matter | ≤ 8% | GB/T 212 |
| Oxygen Content | 15%-30% | Elemental Analysis (EA) |
| Density | 1.35-1.45 g/cm³ (True density) | GB/T 5163 |
| Specific Surface Area | 5-20 m²/g | BET Method (ISO 9277) |
| pH Value | 6-8 (Neutral) | GB/T 1717 |
| Moisture Content | ≤ 2% | GB/T 6284 |
| Thermal Stability | Temperature range: -50°C ~ 300°C (Inert atmosphere) | TGA (Thermogravimetric Analysis) |
| Electrical Conductivity | Semi-conductive (Resistivity: 10³-10⁵ Ω·cm) | GB/T 1410 |
Pre-oxidized Fiber Powder Applications
1. Composite Material Filler
Enhances thermal, mechanical, and flame-retardant properties in epoxy, phenolic, and polyimide resins. Widely used in aerospace, transportation, and defense sectors.
2. Friction Material Additive
Improves heat resistance and wear stability in brake pads and clutch components.
3. Conductive and Anti-Static Plastics
Applied in electronics packaging, conductive coatings, and plastics. Can be blended with carbon black or graphite for resistivity control.
4. Flame-Retardant Plastic and Rubber
Suitable for PA, PP, PU, and PVC products requiring enhanced fire safety and dimensional stability.
5. 3D Printing Filament Enhancer
Serves as a functional additive for engineering polymers like PPS and PEEK.
6. Battery Additive (Emerging Use)
Functions as a conductive agent or structural support in lithium and sodium battery systems.
