The thermal conductivity of epoxy resins cured with various aliphatic amines is measured from room temperature to 150°C. The thermal conductivity increases with rising temperature below the glass transition temperature, Tg, and levels off or decreases with temperature above Tg. It is observed that the thermal conductivity increases linearly with increasing crosslink density as estimated from the measurement of shear modulus in the rubbery state, and that its negative temperature coefficient decreases with increasing crosslink density in the rubbery state. An empirical equation is also derived for the thermal conductivity, λ, of amorphous polymers;
The left side of the equation is estimated for the samples as well as for other various amorphous polymers, and they are both in agreement with the constant of the equation.