Staple Fiber Reinforcement

Match the carrier to your base rubber

All four grades carry the same 40% active aramid pulp fiber — the difference is the carrier system, matched to EPDM, NBR, NR, or CR. Choosing the grade that matches your base polymer supports smoother incorporation and more even fiber dispersion during mixing.

Dial in dosage to your reinforcement target

The wide 2.0–20.0 phr range reflects how differently reinforcement needs vary by product — a lightly reinforced hose sits at the lower end, while a product needing significant dimensional stability, like specialty tires, may run toward the higher end.

1. What's the difference between the four APM40 grades?

The active aramid fiber content (40%) is identical across all four — only the carrier system changes, formulated to match EPDM, NBR, NR, or CR base rubber for better compatibility and dispersion.

2. Why use pre-dispersed aramid pulp instead of adding fiber directly?

Raw aramid pulp fiber is difficult to disperse evenly on its own and prone to clumping. Pre-dispersing it into a carrier masterbatch makes it far easier to incorporate uniformly during mixing, which is what actually delivers the reinforcement benefit.

3. What happens at the low end versus the high end of the dosage range?

Lower dosages provide a modest reinforcement boost while preserving flexibility and moldability. Higher dosages increase dimensional stability and tear resistance more significantly but can affect processability, so it's worth testing within your specific compound rather than defaulting to the top of the range.

4. Can APM40 be used in thermoplastic rubber, not just conventional rubber?

Yes — in addition to natural and synthetic rubber, APM40 is also suitable for thermoplastic rubber systems, providing the same reinforcing effect.