Huntsman Araldite LY 5052 / Aradur 5052 Cold-Curing Epoxy System: A Toughened Low-Temperature Cure Solution for Aerosp

Huntsman Advanced Materials' Araldite LY 5052 low-viscosity epoxy resin and Aradur 5052 polyamine hardener form a classic cold-curing epoxy system. It is used in aerospace and industrial composites, tooling, and aircraft repair.

The resin viscosity is 1000–1500 mPa·s at 25°C, while the hardener is 40–60 mPa·s. After mixing, the system shows low initial viscosity, which supports wet lay-up, resin transfer moulding (RTM), pressure moulding, and filament winding.

According to the TDS, the mix ratio is 100 parts Araldite LY 5052 to 38 parts Aradur 5052 by weight, or 100:47 by volume. For a 100 mL mix, pot life is 110–160 minutes at 25°C and 280–320 minutes at 18°C. This makes the system suitable for relatively large parts cured at room temperature.

In terms of cured properties, the neat resin shows a glass transition temperature (Tg) of about 52–55°C after 7 days at room temperature. After post-curing at 80°C for 8 hours, Tg reaches 114–122°C; after 4 hours at 100°C, it is 120–134°C. The maximum attainable Tg is around 130°C, which meets the thermal requirements of many general aviation and industrial composite parts.

For glass-fabric-reinforced laminates—16 layers of E-glass fabric, 45–46% fibre volume, cured 10 h at 80°C—flexural strength is 440–490 MPa, tensile strength is 360–390 MPa, and interlaminar shear strength can reach 60–65 MPa. This shows that the system offers stable mechanical performance even with ambient or moderate-temperature curing.

The system is qualified by the German Aircraft Authority (Luftfahrt-Bundesamt) for glider production, reflecting its maturity in aircraft repair and low-volume composite manufacturing.

From an industry perspective, cold-curing epoxy systems reduce the need for autoclaves and high-temperature tooling. They allow small and medium-sized manufacturers, MRO shops, and research institutions to produce high-quality composites. Araldite LY 5052 / Aradur 5052 represents a typical solution with wide process windows, long working time, and improvable properties through moderate post-cure.