To increase thermal conductivity of the epoxy tung-maleic（namely

Tongma） anhydride adhesives used for the main insulation of resin-rich molding（RRM）

two kinds of h–BN particle sizes were mixed in a fixed proportion and then added into the adhesives to observe high thermal conductivity adhesives. The thermal property

dielectric loss factor

complex permittivity

insulation resistance and breakdown strength of the thermal adhesives with different additive amounts of h–BN were studied by thermal conductivity meter

frequency domain spectroscopy（FDS）

scanning electron microscope（SEM） and high voltage instrument. The relationships between the microstructural variation of composites and the macroscopic dielectric property were analyzed by the dielectric polarization theory. And the interface morphology change between h–BN particles and adhesives in the cross section of composites was observed by scanning electron microscopy. The results show that the thermal conductivity of h–BN–adhesives gradually increases with the increase of h–BN powder content

and the increase rates are rapid at 80%～100%. The influence of h–BN content on the dielectric parameters of h–BN–adhesives can be revealed by FDS curves. The breakdown field strength of h–BN–adhesives decreases first and then increases gradually to nearly the same level of pure adhesives. The high thermal conductivity adhesives not only possess thermal conductivity but also posses other properties which can meet requirements of the large generator main insulation when the additive amount of h–BN is more than 70%.