Tough-Seal 23

Tough-Seal 23 is a tough and durable fast gelling Potting Compound and Sealant with excellent Thermal Cycling Stability.  

Tough-Seal 23 Properties

tough-seal label design
  • Fast gelling
  • High viscosity
  • 225% elongation
  • Shore Hardness: 64A
  • Excellent Thermal Cycling Stability from -40°F (-40°C) to 302°F (150°C)
  • Applications include: airflow sensors, aviation lighting , marine lighting, LED lighting, RF Sensors

Product Specifications: PC2023AB

Tough-Seal 23 is a high viscosity, Glob Top material with a toothpaste like thickness.  This allows for isolated or localized potting as well as perimeter damming of PCB’s and electronics not assembled in housings.  Since sensitive components can be selectively potted, this is the perfect choice for radio frequency applications where RF signals cannot be interrupted.

Tough-Seal 23 has a 10-20 minute working time and a Shore Hardness of 64A, which is similar to the hardness of a car tire.  Tough-Seal 23 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 23 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.  Tough-seal also 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 (MSDS)

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
51 A to 100B
Gel Time at 25°C, Minutes, 100 grams
Shelf Life, Ambient, Part A Bulk (15°C to 35°C)
3 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)
3 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)
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
Click to View Chart
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 Days
46 A
3 Hours
52 A
4 Hours
57 A
1 Week
60 A
1 Month
68 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
540 Co
Steel Bare
530 Co
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 Strength - per 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 Strength - per ASTM D3163, 25°C, psi **
560 Co
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
50 Co
Polyethylene LDPE
20 Co
Polyethylene HDPE
40 Co
Teflon PTFE – Polytetrafluoroethylene
40 Co
Noryl – Polyphenylene Oxide/Polystyrene
220 Co
Ultem Polyetherimide
540 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.

Ready To Talk to Us?

Tough-Seal is bulldog tough and bred to grip and protect, under the most aggressive conditions.

Contact us to discuss your specific application or requirements.