🧩 PA66/6 – Polyamide 66/6 Copolymer

(Technical copolymer resulting from the combination of polyamide 66 with polyamide 6, created to offer a balance between the rigidity of PA66 and the flexibility of PA6. A material with excellent dimensional stability, hardness, and chemical resistance.)

🔹 What is PA66/6

PA66/6 is a copolymeric polyamide resin obtained through the polycondensation of adipic acid, caprolactam, and hexamethylenediamine.

This combination reduces the crystallinity of PA66, making the material more elastic and easier to process without sacrificing thermal resistance. PA66/6 is used in housings, clips, brackets, electrical connectors, and parts requiring mechanical durability and thermal stability.

🔧 Composition

• Polyamide 66 (PA66): 40–60 %
• Polyamide 6 (PA6): 40–60 %
• Additives: thermal stabilizers, UV filters, glass fibers (optional).
• Density: 1.12–1.15 g/cm³
• Melting Point: ≈ 250–260 °C
• Chemical Resistance: Excellent (oils, fuels, mild solvents).
• Continuous Heat Resistance: 110–130 °C.

🚗 Where PA66/6 is used in the automotive industry

Component	Example parts	Observations
Engine Bay	Covers, consoles, fasteners	High resistance to heat and vibration
Connectors / Electrical	Housings, plugs, guides	Good dimensional stability, insulation
Tech / Structural	Clips, supports, fixing parts	Hardness and mechanical strength
Decorative / Interior	Functional covers and frames	Rigidity and stable matte finish

🔧 Welding Temperature and Methods

Method	Optimal Temperature	Observations
Hot Air	260 – 280 °C	Uniform, clean welding
Heat Plate (Mirror)	250 – 270 °C	Solid joint without deformation
Manual Extrusion	250 – 270 °C	Suitable for thick parts

🔩 What to Weld PA66/6 With (Material Compatibility)

PA66/6 has excellent compatibility with all classic polyamides and PA-based technical blends.

✅ Compatible with:

• PA66/6 ↔ PA6 / PA66 / PA610 / PA612 / PA-GF / PC+PA – ideal.
• PA66/6 ↔ PBT / PC+PBT / PET – partially compatible.

❌ Incompatible with:

• PP, PE, PVC, PS, ABS, ASA, pure PMMA – completely different melting points.

💡 ReplastMD Recommendation:

Use PA66/6 rods or reinforced PA66 rods at 260–280 °C. Briefly preheat the part to avoid moisture issues. Slow cooling prevents internal stress and cracking.

🏭 Manufacturers and Trade Names

• BASF: Ultramid® A/C
• DuPont: Zytel® Copolymer
• DSM: Akulon® Copolymer
• Evonik: Vestamid® 66/6

🧠 How to Identify PA66/6

• Engraved marking: >PA66/6<, >PA6.6/6<, >Zytel<, >Ultramid<.
• Semi-matte surface, rigid, slightly elastic.
• Blue flame with nylon smell.
• Softens at ≈ 250 °C without bubbling.
• ReplastMD practical test: If the part behaves like PA66 but is slightly more elastic and easier to weld – it’s a confirmed 66/6 copolymer.

🛠️ PA66/6 Welding at ReplastMD:

At our ReplastMD service center (Chisinau, Ciocana sector), we perform professional PA66/6 welding for technical housings and engine clips, ensuring a tough, heat-resistant, and stable finish.