Highly mechanical strength and thermally conductive bismaleimide–triazine composites reinforced by Al2O3@polyimide hybrid fiber

Bismaleimide–triazine (BT) resins have received a great deal of attention in microelectronics due to its excellent thermal stability and good retention of mechanical properties. Thereafter, developing BT based composites with high mechanical strength , thermal conductivity and dielectric property simultaneously are highly desirable. In this study, one hybrid fiber of Al 2 O 3 nanoparticle (200   nm) supported on polyimide fiber (Al 2 O 3 @PI) with core–shell structure was introduced into BT resin to prepare promising Al 2 O 3 @PI–BT composite. The results indicated that the resultant composites possessed high Young’s modulus of 4.06   GPa, low dielectric constant (3.38–3.50, 100   kHz) and dielectric loss (0.0102–0.0107, 100   kHz). The Al 2 O 3 @PI hybrid film was also conductive to improve thermal stability ( T d5% up to 371   °C), in-plane thermal conductivity (increased by 295% compared to that of the pure BT resin). Furthermore, the Al 2 O 3 @PI–BT composite were employed to fabricate a printed circuit substrate, on which a frequency “flasher” circuit and electrical components worked well.