Issue 30, 2014 - WACKER develops new liquid silicones for radiator gaskets

Wacker has developed a new ELASTOSIL® RT728 liquid silicone
for gasket production in the automotive industry.
Molded parts made of this new silicone are resistant to high temperatures, coolants, and maintain a very low compression set after long-term loads, thus firmly sealing engine radiators and automotive cooling system components
.
The new silicone is suitable for injection molding processes and can also be applied directly to the sealing parts
with the help of metering devices.

ELASTOSIL RT728 liquid silicone has high coolant resistance, and the gasket made of ELASTOSIL RT728 can maintain a compression set rate of less than 30% after being immersed in a coolant at 105°C for 1000 hours.
Under the condition of 125 °C, the deformation rate in the relaxed state after 1000 hours is also less than
65%.
This high resilience enables the elastomer to have a stable bonding pressure, resulting in excellent sealing performance
in the sealing groove.
In addition, the overall characteristics of ELASTOSIL® RT728 remain unchanged
even under long-term loads.

ELASTOSIL RT728 can be used in injection molding processes to achieve cost-effective mass production
of molded parts.
Alternatively, the liquid silicone can be applied directly to the sealing parts
with the help of metering devices.
ELASTOSIL RT728 meets all technical requirements for the production of two-component composite components in this process, thanks to its shear thinning properties and self-adhesive function, suitable for processing in
metrology equipment.
Some automotive suppliers, such as the MAHLE Group in Stuttgart, Germany, have started using it to produce radiator components
.
（Amy）