(Jiangxi New Materials Co., Ltd.)

Recently, WACKER has successfully developed a new silicone thermally conductive filler for the electronics industry. The silicone rubber product, SEMICOSIL® 961 TC, is an ideal thermal conductive material for thermal connections in electronic circuits and also ensures efficient heat dissipation management. The product is characterized by good flow and workability properties, as well as extremely low wear rates on the mixing and metering equipment used.

SEMICOSIL® 961 TC is a highly filled two-component silicone rubber that uses platinum-catalyzed addition curing at room temperature to form a soft The vulcanized rubber of silicone elastomers, which are elastic and have a sticky surface, can achieve a thermal conductivity of 2 W/(m·Kelvin) and also has electrical insulation properties. SEMICOSIL® 961 TC silicone rubber is an anti-sag material before curing, but under the action of shear forces, such as when mixing or metering, it can obtain better flow properties. The product’s shear-thinning properties are designed to allow the silicone rubber to be transported through the machine without difficulty for in-line coating, allowing manufacturers to achieve high dosing speeds and extremely high dosing accuracy.

(Jiangxi New Materials Co., Ltd.)

SEMICOSIL® 961 TC can exert an excellent heat dissipation effect between electronic circuits and heat sinks. When used, the thermally conductive gap filling material is applied to the heat sink and then covered, or the circuit board is fixed using a vacuum connection process. When pressure is applied, the thermally conductive gap filler forms a continuous film that conforms closely to the surfaces of both adherends and perfectly balances irregularities and tolerances on the substrate surface. In addition, the film maximizes the contact area and speeds up heat transfer.

The film cures into a silicone coating between adherends. This soft silicone coating always ensures the component’s morphological stability, even in the face of frequent temperature changes and vibrations. In addition, the new filler is suitable for a wide temperature range: its performance remains unchanged from minus 45 degrees Celsius to above zero 180 degrees Celsius. This excellent high temperature resistance, thermal shock resistance and vibration absorption performance are of great significance to application fields such as automotive electronics or electric vehicles.

SEMICOSIL® 961 TC is a two-component formulation that, despite its high filler content, is relatively subject to wear on the mixing and metering equipment used for coating. It is low, and the wear on components such as delivery pumps is much lower than that of other highly filled silicone rubbers, which can greatly extend the service life of mixing and metering equipment and bring significant cost advantages to product processing.

This new thermally conductive gap filling material contains almost no volatile components. Multiple studies have shown that the fire safety performance of this silicone product meets the requirements of the UL94 plastic flame retardant rating V-0 issued by Underwriter Laboratories.