Chemetall Naftoseal® MC 238 B-2, Fuselage and Fuel Tank Sealant, Polysulfide, Paste, Cream

Naftoseal® MC-238 class B is a two-component, manganese dioxide cured polysulfide polymer system providing excellent fuel tank and fuselage seals. It has outstanding resistance to aviation gasoline and jet fuel, as well as resistance to the chemicals and petroleum products used in the aircraft industry. Naftoseal® MC-238 class B maintains its flexibility and bond strength on most metal substrates like aluminum, stainless steel, steel, titanium, composite and many coatings under extremes of temperature, weathering and stress. Naftoseal® MC-238 class B techkits can be mixed by MCI-Mixer or by appropriate two-component mixing and dosing systems. The mixed compound is a thixotropic paste easily applied by extrusion, injection gun or spatula. It has excellent tooling properties. For a good surface finish Naftosmooth® can be used after application.

Features
• Free of chrome and solvents/low in solvent content
• Low temperature flexibility
• Fast tack-free and cure times
• Good adhesion to various substrates
• Excellent chemical resistance
• High elasticity and resilience
• Good thixotropic properties, no slump

Technical Information
• AIMS 04-05-001 and 04-05-002
• MDL 6057
• NTA 65361

Specifications
• Series: MC-238 B-2
• Base Type: Polysulfide
• Form: Paste
• Color: Cream
• Odor/Scent: Polysulfide-Like
• Composition: 50 to 100% Polysulfide Polymer
• Curing Time: 48 hr
• Specific Gravity: 1.5 g/cc
• Viscosity: 1500 Pa-s
• Tensile Strength: 2 N/sq-mm
• Applicable Materials: Aluminum, Composite, Stainless Steel, Steel, Titanium
• Temperature Rating: -67 to 266 deg F Service
• Elongation: >400 %
• Non-Volatile Content: 97.5 %
• Shelf Life: 6 months
• Application Time: 2 hr
• Flash Point: 230 deg C
• Tack-Free Time: 14 hr

Applications
• For all aircraft applications requiring sealants