PPG PS 872 Class B is a conductive lightning strike, corrosion inhibitive sealant. Service temperature is −55 to 121 °C, with intermittent excursions up to 135 °C. The cured sealant maintains electrical continuity in highly torqued fay surfaces for certain aircraft applications, acts as a barrier against corrosion on aluminium alloys and between dissimilar metals, and resists intermittent exposure to jet fuel and aviation gasoline. It is a two-part, aluminium filled, manganese dioxide cured polysulfide, a low sag, thixotropic paste applied by extrusion gun or spatula. Tests are run to Lockheed STM40-114 Class B methods.
Application Properties (B-2)
- Colour: A black, B white, mixed light grey; mix ratio by weight 17:100
- Base viscosity 10,000 P (1000 Pa·s); slump 5.08 mm
- B-2: application life 2 hours; tack free under 36 hours; 30 Shore A in 72 hours
Performance
- Specific gravity 1.58; non-volatile content 92%; hardness 55 Shore A
- Peel: 120 N/25 mm after JRF, 111 N/25 mm after JRF/salt water, 100% cohesive
- Tensile strength 1724 kPa (250 psi); elongation 200%; 1379 kPa after 7 days at 121 °C
- No corrosion after 20 days in salt water/JRF; no cracking or loss of adhesion at −54 °C
Storage
- At least 6 months below 27 °C in unopened containers
| Packing | 6 OZ or 1 PT |