Naftoseal NAFTOSEAL MC-780A-2 (130-ml-Kit)

Naftoseal® MC-780 Class A

Overview

Naftoseal® MC-780 Class A is a two-component, manganese dioxide-cured polysulfide sealant designed for aircraft fuselage and fuel tank sealing applications. It provides high flexibility, strong adhesion, and excellent resistance to aviation fuels, petroleum products, and a wide range of aerospace chemicals. The system is engineered for long-term performance under extreme environmental, thermal, and mechanical stress conditions.

Key Technical Specs

• Product Type: Two-component polysulfide sealant
• Base Chemistry: Manganese dioxide-cured polysulfide polymer
• Colour: Grey / Brown (mixed system)
• Density: ? 1.25 g/cc
• Non-volatile content: 92 � 2%
• Service Temperature: -55°C to +130°C
• Short-term Temperature Resistance: Up to +182°C
• Elongation: ~200%
• Tensile Strength: ? 1.5 N/mm²
• Shore A Hardness: ~45 (after 14 days)

Mixing & Application Data

• Mix Ratio (by weight): 100 : 9
• Mix Ratio (by volume): 100 : 6.4
• Application Methods: Extrusion, injection gun, spatula, brush
• Viscosity: Base 50�200 Pa�s; hardener up to 400 Pa�s
• Application Life: 0.5�2 hours (grade dependent)
• Tack-Free Time: 4�14 hours
• Full Cure: 8�24 hours (at 23°C)

Approvals & Specifications

• Aerospace fuel tank and fuselage sealant specification system
• Designed for use in aircraft structural and sealing applications

Typical Applications

• Aircraft fuselage sealing
• Fuel tank sealing systems
• Sealing of metal, composite, and coated substrates
• High-performance aerospace structural sealing
• Sealing under thermal cycling and fuel exposure conditions

Key Features & Benefits

• Excellent resistance to aviation fuels and petroleum products
• Maintains flexibility under extreme temperature variation
• Strong adhesion to aluminium, steel, titanium, and composites
• High elongation for dynamic structural movement
• Long-term durability in harsh aerospace environments
• Can be applied with standard two-component dispensing systems

Surface Preparation

• Clean surfaces using approved aerospace cleaning systems prior to application
• Remove all grease, oils, and contaminants before sealing
• Use lint-free wipes to avoid contamination
• Composite and coated substrates may require adhesion promoter

Packaging & Storage

• Available in Techkits, pails, and drums
• Shelf life: 6 months (stored below 26°C, unopened)
• Protect from excessive heat during storage

Application Notes

• Mix thoroughly using controlled mechanical mixing systems
• Adjust curing speed by temperature control (max 60°C)
• Apply within specified working time window depending on grade
• Ensure correct tooling for uniform seal application

Why This Product is Used in Aerospace

• Critical fuel tank sealing performance
• Reliable adhesion across multiple aerospace substrates
• High chemical resistance to aviation fuels and fluids
• Flexible seal integrity under structural movement

Safety & Handling

• Refer to Safety Data Sheet before use
• Follow controlled mixing and handling procedures
• Avoid contamination of base and hardener components

Manufacturer Information

• Product: Naftoseal® MC-780 Class A
• Manufacturer: Chemetall GmbH (BASF Group)
• Application: Aerospace fuel tank and fuselage sealant