Excellent Wideband Acoustic Absorption of a Multifunctional Composite Fibrous Panel with a Dual-Pore Network from Milled Corrugated Box Wastes

A multifunctional composite fibrous sound-absorption panel was acquired via sustainable fabrication from milling corrugated cardboard box wastes to unleash its fibrous property, creating a high-porosity material. Here, a multifunctional composite fibrous panel from the milled fibers of corrugated cardboard boxes reinforced by cross-linked polyvinyl alcohol as a biodegradable binder is generated. It is designed to have a dual-pore structure with a low density of 0.04 g/cm3, which can withstand a load of 5000 times its weight and is effective for the dissipation of sound at a wide range of frequencies. The prepared material demonstrates an excellent average absorption coefficient of 0.83 at wideband frequency, which is about 280–6300 Hz. The outstanding sound absorption performance of the material is primarily ascribed to its dual-pore architecture, the anisotropic pores interconnected by the random pores formed from the collection of cardboard box fibers within the architecture of the porous material, its thickness, and the concentration of corrugated box fibers. Furthermore, the prepared material manifests a unique porous morphological structure, favorable thermal properties, excellent mechanical stability and sustainability, and superhydrophobic properties. The successful fabrication of this riveting material endowed a promising result that may be applicable for various types of applications.