Preparation method of nano high-frequency and high-speed substrate

The invention discloses a preparation method of a nano high-frequency and high-speed substrate. Belongs to the technical field of copper-clad plate substrate preparation. The preparation method is technically characterized by comprising the following steps: (1) mixing materials: weighing 50-60 parts of a liquid crystal bismaleimide/diallyl diphenyl ether copolymer, 20-30 parts of an organic solvent, 17.5-30 parts of a modified hexagonal nano boron nitride sheet KH570-BNNSs suspension, 1-2 parts of a flame retardant, 0.2-0.5 part of a curing agent and 0.5-1.0 part of a coupling agent, and stirring at a high speed of 1500 r/min for 2-4 hours to obtain a high-frequency and high-speed adhesive; (2) gluing: uncoiling the low-dielectric-constant glass fiber cloth, primarily soaking the low-dielectric-constant glass fiber cloth in a high-frequency and high-speed adhesive to infiltrate one surface of the low-dielectric-constant glass fiber cloth, then removing air in the low-dielectric-constant glass fiber cloth thro