TOUGH-SEAL™ 22 is a tough and durable longer working time 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™ 22 Properties

tough-seal label design
  • Long working time
  • Medium viscosity
  • 225% elongation
  • Shore Hardness: 68A
  • Excellent Thermal Cycling Stability from -40°F (-40°C) to 302°F (150°C)
  • Applications include: safety signal lighting, LED lighting, automotive sensors, wire harness assemblies, Printed Circuit Board Assembly

Product Specifications: PC2022AB

TOUGH-SEAL™ 22 has a longer 60 minute working time and a Shore Hardness of 68A, which is similar to the hardness of a car tire. TOUGH-SEAL™ 22 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™ 22 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 especially 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.

Technical Data Sheet (TDS) and Safety Data Sheet (SDS)

Tough-Seal Series

Physical Properties

Color, Part A

Off White

Viscosity at 25°C, cP, Part A, (RVT #5, 20 RPM)


Specific Gravityat 25°C, Part A


Color, Part B


Viscosity at 25°C, cP, Part B, (RVT #5, 20 RPM)


Specific Gravity at 25°C, Part B
Density at 25°C, lbs/gal, Part B
Color, Mix
Grey / Black
Viscosity at 25°C, cP, Mix, (RVT #5, 20 RPM)
Specific Gravity at 25°C, Mix
Density at 25°C, lbs/gal, Mix
Mix Ratio by Volume
1A to 2B
Mix Ratio by Weight
53A to 100B
Gel Time at 25°C, Minutes, 100 grams
Shelf Life, Ambient, Part A Bulk (15°C to 35°C)
12 Months
Shelf Life, Ambient, Part B Bulk (15°C to 35°C)
12 Months
Shelf Life, Cold, Part A Bulk (-18°C to 3°C)
12 Months
Shelf Life, Cold, Part B Bulk (-18°C to 3°C)
12 Months
Electrical & Thermal Properties
Dielectric Strength, 25°C, Volts/mil
Volume Resistivity, 25°C, Ohm-cm x (10)12
Dielectric Constant, 25°C – 1 MHz
Dielectric Constant, 25°C – 1 kHz
Dielectric Constant, 25°C – 60 Hz
Dissipation Factor, 25°C – 1 MHz
Dissipation Factor, 25°C – 1 kHz
Dissipation Factor, 25°C – 60 Hz
Heat Capacity Cp, 25°C, J/g°K
Thermal Conductivity, 25°C, W/m°K
Coefficient of Thermal Expansion, ppm/°C
(-) 65°C to 75°C
75°C to 100°C
100°C to 150°C
Coefficient of Thermal Expansion, ppm/°F
(-) 85°F to 167°F
167°F to 212°F
212°F to 302°F
Click to View Chart
Hardness vs Temperature
(-75°C / -103°F)
91 A
(-25°C / -13°F)
78 A
5°C / 41°F
70 A
25°C / 77°F
68 A
50°C / 122°F
66 A
66°C / 150°F
69 A
80°C / 176°F
68 A
100°C / 212°F
64 A
120°C / 248°F
54 A
150°C / 302°F
53 A
Click to View Chart
Hardness vs Ambient Cure Time
1 Hour
0 A
2 Hours
10 A
4 Hours
17 A
8 Hours
30 A
12 Hours
35 A
1 Day
48 A
2 Days
56 A
3 Hours
61 A
4 Hours
65 A
1 Week
65 A
1 Month
71 A
Click to View Chart
Mechanical Properties
Tensile Strength per ASTM D638, 25°C, PSI
Elongation per ASTM D638, Type I, 0.125 in, 25°C
Tensile Lap Shear Strength - per ASTM D1002, 25°C, psi *
Aluminum Bare
740 Co
Steel Bare
480 Ad
Steel Ground
600 Co
Primed Steel
560 Co
Galvanized Steel
700 Co
Tin Plated Steel
600 Co
Chrome Plated Steel
490 Co
Tensile Lap Shear Strength - per ASTM D3163, 25°C, psi **
FRP – Polyester Fiberglass
460 Co
Garolite G-9 Melamine/Glass
620 Co
Garolite G-10 Epoxy/Glass
690 Co
Garolite XX Phenolic/Paper
520 Co
Tensile Lap Shear Strength - per ASTM D3163, 25°C, psi **
620 Co
600 Co
PVC – Polyvinyl Chloride
570 Co
CPVC – Chlorinated PVC
670 Co
ABS – Acylonitrile Butadiene Styrene
580 Co
PETG – Polyethylene Terephthalate
610 Co
Lexan – Polycarbonate
630 Co
Nylon 6/6 – Polyamide
620 Co
30 Ad
Polyethylene LDPE
0 Ad
Polyethylene HDPE
20 Ad
Teflon PTFE – Polytetrafluoroethylene
10 Ad
Noryl – Polyphenylene Oxide/Polystyrene
200 Ad
Ultem Polyetherimide
630 Co

Which TOUGH-SEAL™ is Right for you?

TOUGH-SEAL™ is a superior family of KEY sealants available in four standard formulations to fit a variety of potting applications. While all TOUGH-SEAL™ formulations are durable hybrid epoxy elastomers that grip and protect under the most aggressive conditions, they are available in a combination of properties that vary in hardness, gel-time, working time, and flow.

Order your TOUGH-SEAL™ Evaluation Kit Today!

Your Evaluation Kit will include everything you need to perform your own high quality product evaluation for your application.

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TOUGH-SEAL™ PC is bulldog tough and bred to grip and protect, under the most aggressive conditions.

Contact us for help selecting the correct TOUGH-SEAL™ PC for YOUR application!