Thermal conductivity silver-glass adhesives

The main advantages of silver-glass adhesives are their very high thermal conductivities and thermal stabilities compared with filled polymer resin formulations. Thermal conductivities of 65 W/mK to over 80 W/m K are reported. ... 

DM 3030, Silver/glass die attach paste. Thermally Conductive Adhesives Selection Guide. Diemat, a Namics Co, www.diemat.com 2003. 

For high thermal-conductivity adhesives, such as the silver-glass compositions whose thermal conductivities are greater than 20 W/m K, the indirect laser-flash method is used. Unlike the steady-state methods, the flash method does not measure thermal conductivity directly, but measures thermal diffusivity, from which thermal conductivity is calculated as follows ... 

Epoxy adhesives are also easy to modify for special purposes. For example, they can be filled with carbon, silver, or gold to provide electrical conductivity. Other additives can enhance thermal conductivity, while maintaining electrical insulation. Additional performance properties of epoxy-based adhesives that can be modified include impact resistance, shrinkage, glass transition temperature, high-temperature strength, surface specific adhesion characteristics, and chemical or moisture resistance. 

In a completely different area, silver coated hollow glass spheres with particle densities of 1.3 to 1.6g/cm are available for excellent electrical and thermal conductivity, e.g. in special adhesives. 

Figure 29 Determination of thermal expansion coefficients and glass transition temperatures by thermomechanical analysis of conductive adhesives (a) IP 680 silver-filled polyimide analyzed with a dilatation probe (Tg 230°C) (b) self-standing polyimide film studied with an extension probe (Tg 350°C).

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