🧩 HNBR – Hydrogenated Nitrile Rubber

(Saturated elastomeric material resulting from the hydrogenation of nitrile rubber (NBR). HNBR combines NBR’s chemical resistance with high thermal and mechanical stability. It is a thermoset rubber.)

🔹 What is HNBR

HNBR (Hydrogenated Nitrile Butadiene Rubber) is a copolymer where double bonds have been saturated with hydrogen to increase resistance to oxidation, heat, and ozone. At ReplastMD, we handle HNBR as a high-durability material for dynamic seals. It maintains its elasticity up to 160 °C and is fully compatible with modern refrigerants and biodiesel. Being a vulcanized material, it cannot be reshaped or welded by heat.

🔧 Composition & Properties

• Polymer Base: Hydrogenated butadiene + acrylonitrile copolymer.
• Density: 1.00 – 1.25 g/cm³.
• Hardness (Shore A): 50 – 90.
• Operating Range: –40 °C to +160 °C.
• Chemical Resistance: Excellent for oils, fuels, antifreeze, and freons.

🚗 Where HNBR is used in the automotive industry

Component	Example parts	Observations
Engine / Oil Seals	O-rings, seals, covers	Resists mineral and synthetic oils
Fuel Systems	Hoses, valves, fittings	Resists gasoline, diesel, and biodiesel
AC Systems	R134a / R1234yf gaskets	Compatible with modern refrigerants
Dynamic Belts	Timing belts, drive belts	High mechanical and thermal durability

🔧 Welding Temperature and Methods

Method	Compatibility	Observations
Hot Air	❌ Cannot be welded	Vulcanized – does not flow
Heat Plate (Mirror)	❌ Impossible	Chars above 200 °C
Extrusion	❌ N/A	Cannot be reshaped after curing
Chemical Bonding	✅ Recommended	NBR/HNBR specific or cyanacrylate glues

🔩 Compatibility (Bonding)

• ✅ Compatible: HNBR, NBR, FKM, FPM – Excellent.
• ❌ Incompatible: PP, PE, PA, PC, PVC – no adhesion without special primers.

💡 ReplastMD Recommendation: HNBR cannot be thermally welded. For repairs, use high-performance chemical bonding (e.g., Loctite 480). For high-wear technical parts, complete replacement is the only professional solution.