Architecting microbranched bismaleimide resins for superior electromechanical synergy in high-frequency copper-clad laminates

The material has low dielectric constant, high thermal resistance and good mechanical properties, and is applied to high-frequency copper-clad laminate of advanced electronic products. A novel microbranched polyimide (TDMI) was synthesized by incorporating triallyl isocyanurate (TAIC) into bismaleimide prepolymer to form a network structure to enhance toughness and maintain electrical insulation and thermal properties. At 15 wt.% TAIC, TDMI obtained a flexural strength of 160 MPa (increased by 19 times), improved fracture toughness and excellent thermal stability (5% weight loss at 419.8°C). The dielectric constant is reduced to 3.8, and the breakdown field strength reaches 34.66 kV/mm. This study proposes a new resin design strategy that uses a microbranched structure to balance mechanical and electrical insulation properties, making TDMI a strong candidate for the next generation of high-frequency electronic substrates.