Abstract
The thermal boundary resistance RK was measured at niobium-epoxy boundaries in the temperature range above 1 K. RK follows approximately a T2 temperature dependence similar to other epoxy-solid boundaries, while the acoustic mismatch theory predicts a T3 behavior. RK increases by about 10% for Nb going normal conducting. In the mixed state of niobium RK (H) shows a minimum. The reslts are discussed in terms of available theories of Kapitza resistance.