PPG PR-1772 Class B is a low-weight, two-part, chemically curing polysulfide fuselage sealant. It offers as much as 30% weight savings per unit volume over traditional sealants used for these purposes, and the cured sealant keeps excellent elastomeric properties after limited exposure to jet fuel and aviation gas. The low-sag, thixotropic paste is applied by extrusion gun or spatula. Service temperature is −54 to 121 °C (−65 to 250 °F), with intermittent excursions to 135 °C (275 °F).
Application Properties (BMS 5-142 Class B test methods)
- Colour: Part A black, Part B off-white, mixed dark brown
- Base viscosity 9,000 P (900 Pa·s)
- B-1 (25 °C, 50% RH): application life 1 hour; tack free <4 hours; cure to 30 Shore A <7 hours
Performance (cured 14 days at 25 °C)
- Specific gravity 1.09; non-volatile content 91%; ultimate hardness 45 Shore A
- Peel strength (100% cohesive): 26–38 pli (116–169 N/25 mm) on metal and primed substrates
- Tensile strength 190 psi (1311 kPa); elongation 280%
- Hydrocarbon resistance (AMS 2629 JRF, 7 days at 60 °C): weight loss 4.9%; no cracks after a 180° bend over a 3.18 mm mandrel
Storage
- At least 9 months at 4–32 °C (40–90 °F) in unopened containers
| Packing | 6 OZ / 100 ML |