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

Technical 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 provides up to 20% weight savings per unit volume compared to conventional sealants while maintaining durable elastomeric properties, fuel resistance, and reliable adhesion to common aircraft substrates. Designed 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) with 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. Maintains flexibility, durability, and is easy to work, repair, sand, and shave.

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 and tack-free time at 77�F (25�C) varies by grade: 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; non-nutrient fungus resistance.

Peel Strength on Typical Substrates

After 7 days in JRF at 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 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, and pre-mixed frozen cartridges.

Mixing & Handling

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

Surface Preparation

Clean surfaces with approved solvents using lint-free cloths per AMS 3819. Remove contaminants such as oil, dirt, and lubricants. Use approved adhesion promoters when required.

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.