▎ 摘　　要

NOVELTY - Composite sound-absorbing panel comprises a multiscale hole structure, and a composite sound-absorbing material, where the composite sound-absorbing material includes first-level holes with a diameter of less than 2 nm, and a diameter of 0.5-3 µm secondary holes and tertiary holes with a diameter of 0.1-3 mm. The bulk density of the first-stage holes accounts for 5-50% of the total hole bulk density. The bulk density of the second-stage holes accounts for 20-60% of the total hole bulk density. The third-stage hole bulk density accounts for 20-60% of the total hole bulk density. The bulk density of other scale holes accounts for 0-10% of the total bulk density of the holes. USE - Composite sound-absorbing panel for adjusting indoor reverberation. ADVANTAGE - The composite sound-absorbing panel can accurately control the micron size and range of the level holes to ensure that the porous sound-absorbing material has better low-frequency sound-absorbing performance, and has better sound-absorbing performance in a wider frequency range. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing composite sound-absorbing panel with a multi-scale hole structure, which involves mixing adhesives, additives, and microporous template materials with preset shapes with alkaline or acidic solutions to obtain inorganic dispersions, carbonizing the bio-based material at a first specified temperature for a first specified time, mixing with the inorganic dispersion liquid, curing at a second specified temperature for a second specified time to obtain a porous cured material, activating the porous solidified material at a third specified temperature for a third specified time, cooling, neutralizing, washing, drying and pulverizing to obtain porous particles, mixing the porous particles with the porous material according to the first preset mass ratio, and mixing and heat-pressing the organic resin particles to obtain the composite sound-absorbing panel; mixing the porous particles with the porous material according to the second preset mass ratio to obtain the composite sound-absorbing panel.