PPG PR1776MB1/2-B1001 (100-ml-Semkit)

Description

PR-1776M Class B is a low-density, high-temperature Permapol® P-5 modified polysulfide integral fuel tank sealant formulated for aerospace environments. It delivers up to 20% weight savings per unit volume compared to conventional sealants while maintaining outstanding fuel resistance, durable elastomeric properties, and reliable adhesion to common aircraft substrates. Designed primarily for fillet sealing of fuel tanks and fuselage structures, it cures into a resilient rubber that withstands extended exposure to jet fuel and aviation gasoline, with limited resistance to phosphate-ester hydraulic fluids.

Features & Benefits

• Up to 20% weight reduction compared to traditional fuel tank sealants
• High temperature performance to 250°F (121°C) and limited excursions to 360°F (182°C)
• Excellent resistance to jet fuel, aviation gasoline, and common aircraft fluids
• Strong adhesion to aluminum, titanium, composites, and epoxy-primed surfaces
• Good workability, repairability, and sanding/shaving properties
• Maintains long-term flexibility and durability in harsh environmental conditions

Typical Application Properties

• Color: Part A – Black; Part B – Off-white; Mixed – Dark Brown
• Mix Ratio (by weight): B-1/2 = 12:100, B-2 = 10:100
• Base Viscosity: ~11,100 Poise (Brookfield #7 @ 2 rpm)
• Application Life & Tack-Free Time (77°F / 25°C):
  • B-1/2: 0.5 hr life – <8 hr tack-free
  • B-2: 2 hr life – <16 hr tack-free
  • B-4: 4 hr life – <24 hr tack-free
  • B-6: 6 hr life – <30 hr tack-free

Typical Cured Properties

• Specific Gravity: ~1.29
• Nonvolatile Content: ~94%
• Hardness: 50 Shore A (ultimate cure)
• Tensile Strength: ~263 psi (1812 kPa)
• Elongation: ~366%
• Low-Temperature Flexibility: No cracking at -65°F (-54°C)
• Fuel Immersion: Weight loss approx. 4.7% after 7 days @ 140°F in JRF
• Fungus Resistance: Non-nutrient

Peel Strength on Typical Substrates (after 7 days JRF @ 140°F)

• Aluminum (Alodine): ~41 pli (180 N/25 mm)
• Titanium (MIL-T-9046): ~36 pli (158 N/25 mm)
• Epoxy-Primed Composite (BMS 10-20): ~42 pli (184 N/25 mm)

Applications

• Fillet sealing of integral fuel tanks
• Sealing of aircraft fuselage structures
• Weight-critical aerospace sealing applications
• OEM and MRO environments requiring high-performance fuel resistance

Packaging Options

• Two-part Semkit® packages
• Two-part can kits
• Pre-mixed & frozen cartridges

Mixing & Handling

Mix Part A and Part B thoroughly until fully uniform, following the specified mix ratio for the selected Class B work-life grade. Scrape container sides and bottom to avoid unmixed material. Apply to clean, properly prepared surfaces immediately after mixing.

Surface Preparation

Clean surfaces using approved solvents with lint-free cloths in accordance with AMS 3819. Remove contaminants such as oil, dirt, and lubricants. Use PR-148 or other approved adhesion promoters when required by specification or substrate condition.

Storage

• Semkit® / Can kits: Minimum 9 months at 40–80°F (4.5–27°C)
• Pre-mixed frozen cartridges: 28 days at or below –40°F (–40°C)

Compliance

• Meets AMS-3281 and BMS 5-45 performance requirements