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SuihuaFirst PDM-75

Phone: 0750-6680778

Product Description

Pain point you may have faced
Two problems keep coming back. First, thick rubber articles – like tire treads or large molded parts – tend to revert during high‑temperature vulcanization, losing crosslink density and physical properties. Second, when you cure rubber that contacts copper wires or electrical components, traditional sulfur‑based systems leave black stains on the copper, causing electrical failures or cosmetic rejects. You have tried adding more accelerators or switching to peroxide, but each fix creates new issues.

Why PDM‑75 is different
First® PDM‑75 (N,N'‑m‑phenylene bismaleimide) is a multifunctional rubber additive that solves both problems. It works synergistically with sulfur – preventing scorch and even restoring vulcanization after reversion. As an auxiliary curing agent, it significantly reduces the required amount of peroxide, boosting crosslinking efficiency and heat resistance – ideal for high‑temperature vulcanization systems. It also lowers compression set and improves scorch safety.

But the real breakthrough: PDM‑75 can be used as a sulfur‑free curing agent in cable rubber compounds. It completely replaces all sulfur‑containing curatives (such as thiazoles and thiurams), eliminating the source of copper blackening. Your copper wires and connectors stay bright and conductive.

What you gain

No reversion – thick parts retain their properties even after prolonged high‑temperature cure.

Lower compression set – better sealing performance for gaskets and O‑rings.

Reduced peroxide consumption – cost savings and safer processing.

Sulfur‑free curing option – perfect for electrical cables, busbars, and any component in contact with copper.

Real‑world result
A manufacturer of rubber‑insulated copper cables had struggled with black stains on the conductor for years. They replaced their entire thiazole/thiuram sulfur system with First® PDM‑75 at 2 phr. The copper remained completely clean after vulcanization, and the rubber retained excellent tensile strength and heat aging resistance. Their customer – an automotive wiring harness supplier – approved the new formulation immediately.

Typical specifications

Appearance: off‑white to light yellow granules

Active ingredient: N,N'‑m‑phenylene bismaleimide (approx. 75%)

Carrier: EPDM

Recommended dosage: 0.5–2.5 phr (as anti‑reversion or co‑agent)

Packaging: 25 kg carton with inner PE liner

Storage: 12 months in unopened packaging, cool and dry

Try PDM‑75 at no cost
Whether you need to stop reversion in thick parts or eliminate copper stains in cables, PDM‑75 offers a clean solution. We are happy to send you a free sample – test it in your most challenging recipe, no obligation.