High-Strength, Thermally Stable Phthalazinone-Containing Bismaleimide Composites Engineered for Electronic Packaging Substrates

To address the escalating demands imposed by artificial intelligence computations, advanced electronic packaging technologies have increasingly emphasized miniaturization, high integration, and superior stability. Nonetheless, such advancements frequently encounter challenges such as severe heat accumulation, inadequate rigidity, and electrical signal interference. Consequently, there is an urgent need for packaging materials that possess exceptional thermal resistance, elevated flexural modulus, and superior dielectric attributes to satisfy these stringent application criteria. Initiated from a molecular design perspective, this investigation successfully synthesized bismaleimide (BMI)-terminated poly(phthalazinone ether nitrile ketone) (PPENKBMI) and used a biphenyl-structured curing agent, namely, 3,3'-diallylbiphenyldiol (DABP). These were subsequently compounded with 4,4'-bismaleimidodiphenylmethane (BDM) in various proportions to produce a composite matrix. Evaluation results indicate that, due to the pronounced rigidity of the biphenyl structure coupled with the spatial complexity imparted by the naphthalene-containing biphenyl framework, the resultant composites demonstrate outstanding thermal resilience (with <i>T</i>_g exceeding 300 °C), achieve a flexural modulus of 52.3 GPa, and attain a flexural strength of 660.4 MPa. Moreover, the robust skeletal architecture facilitates augmented free volume, leading to a diminished dielectric constant (measured at 4.2 at 10 GHz) relative to conventional BMI resin resins. Furthermore, the composites exhibit commendable performances in terms of processability, thermal durability, peel strength and control over the coefficient of thermal expansion. Collectively, this resin composite showcases exceptional overall properties and holds substantial promise for state-of-the-art electronic packaging applications.