Design of reactive linear polyphosphazene to improve the dielectric properties and fire safety of bismaleimide composites

Author：Zhou, Y. F., Liu, W., Ye, W. B., Chu, F. K., Hu, W. Z., Song, L., Hu, Y.

Journal：Chemical Engineering Journal

DOI:  10.1016/j.cej.2024.148867

Keywords: Electronic packaging materials, Flame retardant, Hydrophobic, Dielectric properties, Toughness, thermal-properties, flame-retardant, phosphorus, Engineering

Abstract: 

The high -frequency transmission of 5th -Generation Mobile Communication Technology (5G) and more integrated mobile terminals pose a challenge to the safety and dielectric properties of existing electronic packaging materials. This work innovatively designs a linear polyphosphazene compound (PABN) with benzonitrile as the reactive side group. The prepared bismaleimide (BMI)/PABN is an excellent dielectric composite material, breaking the technical barrier of balancing fire safety and dielectric performance. With only 1 wt% PABN, the UL94 rating of BMI composite reaches V0, and the impact strength increases by 48.5 %, demonstrating excellent fire safety and toughness. Specifically, the dielectric constant (Dk) of the composite containing 4 wt% PABN is as low as 2.67, far meeting the requirements of 5G. In addition, the glass transition temperature (Tg) of all BMI/ PABN composites is around 290 degrees C, and the initial decomposition temperature exceeds 400 degrees C, indicating potential applications in the integration and miniaturization of microelectronic devices.