Product Specifications: PC2021AB
Tough-Seal 21 is a tough and durable fast gelling Potting Compound and Sealant with excellent Thermal Cycling Stability. This medium viscosity material is self-leveling and flows like honey around electrical components to ensure complete coverage of your entire PCB or electronic assembly.
Tough-Seal 21 has a faster 10-20 minute working time and a Shore Hardness of 64A, which is similar to the hardness of a car tire. Tough-Seal 21 reaches 94% of its full hardness after an overnight cure or with a heat cure of 1 hour at 80°C (176°F). Tough-Seal does not exotherm or shrink during curing, therefore there is no embedment stress induced on the electronic components that could cause damage and failure of the PCB or electronic assemblies. Sensitive electronics can be potted safely with low embedment stress Tough-Seal.
With a high elongation of 225% when fully cured, Tough-Seal 21 maintains exceptional flexibility and thermal cycling stability from –40°C to 150°C (-40°F to 302°F) without pulling back, wilting, or cracking. This ensures a tough seal that will stop moisture or other contaminants from damaging sensitive PCB’s and electronics.
Tough-Seal has very aggressive adhesion to aluminum, making it a perfect choice for potting aluminum housings in LED lighting applications. Tough-seal bonds extremely well with most polymers. For housing and wire insulation materials that are exceptionally difficult to bond to, we offer our KEY PR1200 PRIMER, an aggressive adhesive promoter that is simple to use.
Product Information Bulletin (PIB) and Safety Data Sheet (SDS) Downloads
PIB (Key PR1200 Primer)
SDS (Key PR1200 Primer)
(Typical Properties)
| Physical Properties | ||
| Color, Part A | Off White | |
| Viscosityat 25°C, cP, Part A, (RVT #5, 20 RPM) | 7,000 | |
| Specific Gravityat 25°C, Part A | 1.32 | |
| Densityat 25°C, lbs/gal, Part A | 11.0 | |
| Color, Part B | Black | |
| Viscosityat 25°C, cP, Part B, (RVT #5, 20 RPM) |
11,000 | |
| Specific Gravityat 25°C, Part B | 1.28 | |
| Dielectric Constant,25°C – 60 Hz | 5.75 | |
| Dissipation Factor, 25°C – 1 MHz | 0.026 | |
| Dissipation Factor, 25°C – 1 kHz | 0.028 | |
| Dissipation Factor, 25°C – 60 Hz | 0.064 | |
| Heat CapacityCp, 25°C, J/g°K | 1.37 | |
| Thermal Conductivity,25°C, W/m°K | 0.26 | |
 |
Coefficient of Thermal Expansion, ppm/ °C | |
| (-) 65°C to 75°C | 135 | |
| 75°C to 100°C | 0 | |
| 100°C to 150°C | 75 | |
| Coefficient of Thermal Expansion, ppm/°F | ||
| (-) 85°F to 167°F | 75 | |
| 167°F to 212°F | 0 | |
| 212°F to 302°F | 42 | |
| Hardness vs Temperature | ||
 |
(-75°C / -103°F) | 88 A |
| (-25°C / -13°F) | 75 A | |
| 5°C / 41°F | 69 A | |
| 25°C / 77°F | 64 A | |
| 50°C / 122°F | 62 A | |
| 66°C / 150°F | 61 A | |
| 80°C / 176°F | 62 A | |
| 100°C / 212°F | 57 A | |
| 120°C / 248°F | 51 A | |
| 150°C / 302°F | 47 A | |
| Hardness vs Ambient Cure Time | ||
 |
1 hour | 15 A |
| 2 hours | 26 A | |
| 4 hours | 31 A | |
| 8 hours | 35 A | |
| 12 hours | 35 A | |
| 1 day | 39 A | |
| 2 day | 46 A | |
| 3 days | 52 A | |
| 4 days | 57 A | |
| 1 week | 60 A | |
| 1 month | 68 A | |
| Mechanical Properties | ||
| Tensile Strengthper ASTM D638, 25°C, PSI | 450 | |
| Elongationper ASTM D638, Type I, 0.125 in, 25°C | 225% | |
| Co=Cohesive Ad=Adhesive | ||
| Tensile Lap Shear Strengthper ASTM D1002, 25°C, psi ** | ||
 |
Aluminum Bare | 540 Co |
| Steel Bare | 530 Ad | |
| Steel Ground | 480 Co | |
| Primed Steel | 530 Co | |
| Galvanized Steel | 560 Co | |
| Tin Plated Steel | 470 Co | |
| Chrome Plated Steel | 560 Co | |
| Tensile Lap Shear Strengthper ASTM D3163, 25°C, psi ** | ||
 |
FRP – Polyester Fiberglass | 540 Co |
| Garolite G-9 Melamine/Glass | 530 Co | |
| Garolite G-10 Epoxy/Glass | 550 Co | |
| Garolite XX Phenolic/Paper | 570 Co | |
| Tensile Lap Shear Strengthper ASTM D3163, 25°C, psi ** | ||
 |
Acrylic | 560 Co |
| Acrylic/PVC | 430 Co | |
| PVC – Polyvinyl Chloride | 530 Co | |
| CPVC – Chlorinated PVC | 660 Co | |
| ABS – Acylonitrile Butadiene Styrene | 500 Co | |
| PETG – Polyethylene Terephthalate | 610 Co | |
| Lexan – Polycarbonate | 520 Co | |
| Nylon 6/6 – Polyamide | 520 Co | |
| Polypropylene | 50 Ad | |
| Polyethylene LDPE | 20 Ad | |
| Polyethylene HDPE | 40 Ad | |
| Teflon PTFE – Polytetrafluoroethylene | 40 Ad | |
| Noryl – Polyphenylene Oxide/Polystyrene | 220 Ad | |
| Ultem – Polyetherimide | 540 Co | |
| **20 mil Bondline, 1 in x 4 in Adherands, 1 in Overlap | ||
