Technical Parameters of Semi-Aromatic Nylon PA6I/6T (PA6T/6I, PPA)
Note: PA6I/6T is a semi-aromatic nylon copolymer made from hexamethylenediamine, terephthalic acid and isophthalic acid. It can be compared with transparent PA12 and PA66. Parameters vary slightly among manufacturers (EMS, BASF, domestic brands). Properties will be greatly improved after glass fiber reinforcement.
1. Basic Physical Properties
– Density: 1.18 g/cm³ (ISO1183)
– Saturated water absorption (23℃, 50%RH): 1.7%~2.2%; 24h water immersion absorption ≈0.35%. Much lower than PA66 (saturated water absorption of PA66 ≈8%), good dimensional stability
– Molding shrinkage: 0.7%~1.1% (flow direction); can drop to 0.2~0.4% with glass fiber filling
– Appearance: Natural amber translucent / opaque, flame-retardant modification available
2. Thermal Properties (Core Advantages)
– Melting point Tm: 310~325 ℃ (DSC)
– Glass transition temperature Tg: 125–140 ℃
– Heat deflection temperature HDT (1.8 MPa, unreinforced): 125~140℃; 270~285℃ for 30% glass fiber reinforced grade
– Long-term continuous service temperature: 130–150℃ (in air), short-term peak temperature 180℃
– Flame retardancy: Natural LOI ≈27%; can reach UL94 V-0 (0.8mm) with flame retardant additive
3. Mechanical Properties (Dry state, 23℃)
– Tensile strength: 85–105 MPa
– Tensile modulus: 3200–3800 MPa
– Elongation at break: 4–8 %
– Flexural strength: 120–140 MPa
– Charpy notched impact strength: 5–8 kJ/m² (rigid material, lower toughness than PA12)
4. Chemical Resistance & Electrical Properties
– Chemical resistance: Resistant to oil, coolant and most solvents; better hydrolysis resistance than PA66, suitable for hot-humid working conditions; not resistant to concentrated strong acid
– Volume resistivity: 1×10¹² Ω•m
– Dielectric strength: 26–28 kV/mm
– Comparative Tracking Index (CTI): ≥600V, excellent electrical performance, ideal for connectors
5. Processing Reference for Injection Molding
– Melt temperature: 330–350 ℃
– Mold temperature: 130–160 ℃ (high mold temperature ensures crystallization and stable dimension)
– Thorough drying required: 120℃ for 4–6 hours, moisture content ＜0.05% to avoid silver streaks and bubbles
✅ Brief Comparison with PA66 (for your foreign customers)
1. Temperature resistance: PA6I/6T withstands much higher temperature, long-term at 140℃; PA66 long-term 80–100℃
2. Water absorption: PA6I/6T absorbs little water with stable dimension; PA66 absorbs much water and tends to deform
3. Toughness: PA6I/6T is stiffer; PA12 features best toughness, transparency and low friction
4. Cost: PA6I/6T is more expensive than PA66, classified as high-temperature specialty nylon