Dolphin 120 High Temp 300°C Silicone Sealant

Dolphin 120 High Temp 300°C Silicone Sealant is a one part moisture curing , RTV (Room Temperature Vulcanizing) silicone that cures to form a tough rubber.Dolphin 120 HT was specifically formulated to be used where operating temperatures up to 300°C are reached intermittently. 120 HT sealant contains red iron oxide which enables it to be a true high temperature silicone that will continue to be resilient at extreme temperature.Formulated to perform at 300°C.


Industrial ovens, HVAC, High temperature general sealing and waterproofing, Automotive applications, water and oil pumps seals, wire and cable insulation, Furnace and Humidifier gasket, Engine components, Telecommunications including coaxial cable connectors

Application instruction

Application surface should be clean, dry, sound and free from all contaminants. ie, dust, greese, rust etc.Clip off tip of spout at 45 degree angle to desired size. Load cartridges into caulking gun & apply using steady, even pressure to completely bridge joints. Smooth caulk using a finger, caulk smoother or back of a spoon dipped in soapy water solution. Wipe away excess with cloth or paper towel prior to cure.

Storage and Shelf life

When stored in original unopened container at or below 25°C, Dolphin 120 Silicone Sealant has a shelf life of 18 months from the date of Manufacturing. Containers should always be kept sealed when not in use. After a container has been opened and the entire contents have not been used, extrude 3/8’’ of material past nozzle opening. When ready to use, pull out cured plug. Sealant is ready to use.


Application Video

Dolphin 120 HIGH TEMPERATURE 300°C sealant is available in HDPE cartridges , 90 ml tubes and 200 liters drum.


Typical Properties



Black, Clear, Gray and Red

Skin Over Time

?10 min

Tack Free Time


Specific Gravity

1.01±0.01 g/cm3


23 points

Depth Cure

> 2.4/ Day

Viscosity Flow

Non sag

Tooling Time

15 min



Tensile Strength

1.30 N/mm2

Elongation Approx


Service Temp

-40 upto 300°C

Young’s Modulus

0.24 MPa



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