Facile Construction of Hyperbranched Polyphenylsiloxane-Modified Epoxy Resins with Excellent Low Dielectric Properties for Electronic Packaging

The booming development of next-generation communication technologies urgently requires high-performance electronic packaging materials with facile construction. Hereby, We first synthesized hyperbranched polysiloxane with phenyl, propyl, and hydroxyl groups as terminals. Subsequently, we incorporated it into bisphenol A epoxy resin using covalent cross-linking agents to cure it for electronic packaging applications. The manufactured DGEBA/HBPSi/MeTHPA resins not only had a lower curing temperature, which facilitates processing, but also exhibited significantly enhanced toughness, thereby increasing the usage limit of packaging materials. Differential scanning calorimetry (DSC) data were utilized to explore the nonisothermal curing behaviors of the system. The DSC thermogram exhibited distinct curing stages within the temperature range of 75–225 °C, and the average activation energies computed using the Kissinger and Ozawa methods were 68.42 and 71.73 kJ/mol, respectively. Additionally, dynamic mechanical analysis (DMA) and fracture morphology analysis demonstrated that the DGEBA/HBPSi/MeTHPA resin had excellent storage modulus, enabling it to better resist external impacts, and its fracture surface displays ductile fracture characteristics. Meanwhile, compared to the pure epoxy resins, the impact strength, flexural strength, and elongation at break were significantly increased by 153.85, 47.76, and 205.94%, respectively. Notably, the DGEBA/HBPSi/MeTHPA resins have excellent dielectric properties and exhibited a low dielectric constant (Dk of 2.82) and dielectric dissipation factor (Df of 0.02050) at 100 MHz. The variation of optical parameters and complex dielectric constant of modified epoxy resin was also studied by spectroscopic ellipsometry, and the results showed that it has excellent optical properties. The work demonstrates that the DGEBA/HBPSi/MeTHPA resins have the potential to be extensively used in the area of electronic packaging in an approach that seems promising.