PR-148 is an adhesion promoter that enhances the coupling characteristics of polysulfide compounds to a wide variety of substrates. It is a one-part compound applied by brush or clean gauze. The product is fully qualified to AMS 3100 Class 1 and PRC-DeSoto International specification test methods. It does not soften finishes and dries in 15 minutes at 25 °C (77 °F).
Specifications and Approvals
- AMS 3100 Class 1
Typical Properties
- Color: blue; appearance: free of particles
- Dry time (30–70% RH): 15 minutes at 25 °C (77 °F); 45 minutes at 16 °C (60 °F); 45 minutes at 4 °C (40 °F)
- Specific gravity: 0.81; flash point (PMCC): -5 °C (23 °F)
- Peel strength, 100% cohesion (PR-1440 B-2 / AMS-S-8802 sealant), NaCl-H2O immersion, 7 days at 60 °C (140 °F): MIL-P-23377 (epoxy primer) 73 pli (325 N/25 mm)
Application
- Clean surfaces with solvent immediately before application, using a new lint-free cloth conforming to AMS 3819.
- Apply a thin coat of PR-148; after drying, wipe off the excess and start the sealing procedure.
- If the surface becomes contaminated or sealing is not done within 8 hours, repeat the priming procedure.
- Where solvent crazing is a concern, consider PR-142 instead.
Packaging and Shelf Life
- At least 6 months below 27 °C (80 °F) in original, unopened containers
- Hygroscopic; keep free of moisture and discard if it becomes cloudy or a precipitate forms.
| Packing | 2 OZ or 1 Pint |
| Color | Blue or Clear |