Preparation and Properties of YP50S/TPOSS/Si-MMT Synergistically Modified Cyanate Ester Resin Carrier Film for High-Frequency and High-Speed Copper-Clad Laminate

To meet the demands for high-frequency, high-speed copper-clad laminates characterized by low dielectric constant, low loss, high heat resistance, and good mechanical performance, this study employs cyanate ester resin (CE) as the matrix. Additionally, polyphenylene oxide resin (YP50S), TPOSS, and silicon-intercalated montmorillonite (Si-MMT) are introduced for synergistic modification. Basalt fiber is further incorporated to prepare composite carrier films. The results demonstrate that YP50S significantly accelerates the curing of CE, resulting in a reduction in the curing peak temperature by 89 °C at a concentration of 10 wt%. TPOSS further amplifies this effect. Si-MMT markedly enhances the overall properties, with 3 wt% yielding optimal performance. The dielectric constant decreases to 3.3 at 1 × 107 Hz while maintaining a low dielectric loss. This strategy effectively enhances the overall performance of CE-based composites.