High-efficiency flame retardant, heat insulating, and sound absorbing three-phase laminated composite based on spacer fabric/polyurethane/silica aerogel

Polyurethane (PU) foam is widely used in various industries due to its advantages in heat preservation, heat insulation, sound absorption, etc., but this kind of material is extremely flammable and has fire hazards in use. Furthermore, the material compressive properties are insufficient, and the sound absorption performance of medium and low frequencies at low thickness also needs to be improved. Based on the above, in order to comprehensively improve the properties of polyurethane, a ternary layer-stacked composite consisting of spacer fabric/polyurethane/silica aerogel (FPS composite) was innovatively designed and prepared in this study. In the FPS composite, the spacer fabric surface layer functions similarly to the wall mesh fabric, which successfully solves the cracking problem of SiO2 aerogel layer. In addition, the FPS composite reinforced by the spacer fabric with chain + inlay and hexagonal mesh surface structure has compressive modulus of 1.25 MPa and 0.8 MPa, respectively. The thermal conductivity of the two FPS composites is 0.0479 and 0.0452 (W m−1 K−1), respectively, and the FPS composite can achieve flame self-extinguishing within 40 s. In addition, the “filled microperforated plate-like” structure implemented by the introduction of spacer yarns gives the material resonance sound absorption characteristics, the FPS composite has a noise reduction coefficient value of 0.26 at a low thickness of 7.5 mm. To sum up, the composite materials prepared in this study can expand the application field of PU foam and adapt to industries that have requirements for heat preservation, heat insulation, fire prevention, sound absorption, and other aspects.