Permatex® High-Temp Red RTV Silicone Gasket Maker – P/N 81409 (26C, 11 oz Tube)

Permatex® High-Temp Red RTV Silicone Gasket Maker(81409 / 26C) is a single-component, room-temperature vulcanizing (RTV) silicone sealant designed to create durable formed-in-place gaskets (FIPG) for high-temperature mechanical assemblies. The material cures upon exposure to atmospheric moisture to form a tough, flexible silicone rubber gasket that resists shrinking, cracking, and hardening during thermal cycling.
The red non-sag paste formulation allows controlled bead application and reliable gap filling on metal components, making it suitable for sealing flange surfaces and gasket interfaces exposed to heat and vibration. The sealant provides excellent adhesion and flexibility, allowing assemblies to maintain sealing integrity during mechanical movement and expansion.
Permatex High-Temp RTV Silicone Gasket Maker is commonly used as a replacement for conventional cut gaskets in industrial and automotive maintenance operations. Typical uses include sealing panels, window plates, oven doors, flues, and high-temperature equipment housings, as well as mechanical assemblies exposed to heat and automotive fluids.
Once applied, the silicone sealant becomes tack-free within approximately one hour and fully cures in about 24 hours, forming a flexible gasket capable of withstanding continuous high-temperature operation.
The cured gasket maintains excellent resistance to motor oil, transmission fluid, alcohol, and antifreeze solutions, making it suitable for demanding industrial sealing environments where durability, flexibility, and heat resistance are critical.
Permatex High-Temp RTV Silicone Gasket Maker is widely used by maintenance engineers, equipment manufacturers, automotive technicians, and industrial fabricators requiring a reliable high-temperature silicone gasket sealant.
Key Selection / Performance Parameters
Chemical Type: Acetoxy RTV silicone rubber
Appearance: Red non-sag paste
Odor: Mild acetic
Specific Gravity: 1.05
Extrusion Rate: >220 g/min @ 25°C
Flash Point: >93°C (>200°F)
Tack-Free Time: ~1 hour
Full Cure: ~24 hours
Hardness: >20 Shore A
Elongation: >350%
Tensile Strength: >1.5 N/mm² (>218 psi)
Gap Fill Capability: Up to 0.25 inch
Temperature Resistance:
• Continuous: -54°C to 316°C (-65°F to 600°F)
• Intermittent: -54°C to 343°C (-65°F to 650°F)
Chemical Resistance: Motor oil, transmission fluid, alcohol, antifreeze solutions
Typical Applications: Formed-in-place gaskets, high-temperature equipment sealing, oven doors, flues, industrial machinery