PPG PR-1784 Class B is a fast-curing, chromate-free* aircraft windshield and canopy sealant. It is designed for fillet sealing of properly prepared glass, polycarbonate, acrylic and other aircraft substrates and is specifically formulated not to craze substrates. It is a two-part polysulfide liquid polymer; the mixed material is a thixotropic paste applied by extrusion/injection gun or spatula that does not flow from vertical or overhead surfaces. The cured sealant has excellent UV and weather resistance. Service temperature is −43 to 120 °C (−45.4 to 248 °F). (*Chromium is not intentionally added to the formulation.)
Application Properties
- Colour: Part A black, Part B grey, mixed black; mix ratio by weight A:B 14:100
- Base viscosity 1000 Pa·s (10,000 P); slump (B-1/2) 6 mm
- B-1/2 (23 °C, 50% RH): application life ½ hour; tack free 4 hours; 30 Shore A in 6 hours
Performance (cured 14 days at 25 °C)
- Specific gravity 1.4; non-volatile content 97%; ultimate hardness 40 Shore A
- Peel strength 7 N/mm (100% cohesive): alclad 2024 aluminium, stainless steel, titanium, P60, F70; glass and acrylic with PR-186, polycarbonate with PR-141
- Lap shear 1.8 MPa; tensile strength 1.8 MPa; elongation 600%
- Excellent resistance to water, alcohols, synthetic and petroleum-based lubricating oils, petroleum-based hydraulic fluids and de-icing fluid; no cracking or loss of adhesion at −43 °C
Storage
- Two-part kits and SEMKIT® cartridges; 6 months at 4–27 °C (39–81 °F) in unopened containers
| Packing | 6 OZ |