Directionally Antagonistic Graphene Oxide-Polyurethane Hybrid Aerogel as a Sound Absorber

Abstract

Innovative sound absorbers, the design of which is based on carbon nanotubes and graphene derivatives, could be used to make more efficient sound absorbing materials because of their excellent intrinsic mechanical and chemical properties. However, controlling the directional alignments of low-dimensional carbon nanomaterials, such as restacking, alignment, and dispersion, has been a challenging problem when developing sound absorbing forms. Herein, we present the directionally antagonistic graphene oxide-polyurethane hybrid aerogel we developed as a sound absorber, the physical properties of which differ according to the alignment of the microscopic graphene oxide sheets. This porous graphene sound absorber has a microporous hierarchical cellular structure with adjustable stiffness and improved sound absorption performance, thereby overcoming the restrictions of both geometric and function-orientated functions. Furthermore, by controlling the inner cell size and aligned structure of graphene oxide layers in this study, we achieved remarkable improvement of the sound absorption performance at low frequency. This improvement is attributed to multiple scattering of incident and reflection waves on the aligned porous surfaces, and air-viscous resistance damping inside interconnected structures between the urethane foam and the graphene oxide network. Two anisotropic sound absorbers based on the directionally antagonistic graphene oxide-polyurethane hybrid aerogels were fabricated. They show remarkable differences owing to the opposite alignment of graphene oxide layers inside the polyurethane foam and are expected to be appropriate for the engineering design of sound absorbers in consideration of the wave direction.

Ultralight Graphene Oxide/Polyvinyl Alcohol aerogel for broadband and tuneable acoustic properties

“…Recently, metamaterials have been considered for the same purpose, exploiting geometrical factors to tune the acoustic behaviour over specific frequencies 7,8 . Cellular absorbers can be distinguished in organic, hybrid, or inorganic, according to their chemical composition 4 , with a recent growing interest toward the use of carbon-based materials 9,10 . Particularly, Graphene Oxide (GO) can be considered as an ideal candidate for the engineering of novel aerogels, due to its peculiar chemical structure consisting of a two-dimensional (2D) lattice of sp 2 hybridized carbon atoms with oxygen functionalities 11 .…”

GRAPHENE OXIDE MICROCAPSULES (GOMs) WITH LINSEED OIL CORE VIA PICKERING EMULSION METHOD: EFFECT OF DISPERSE SPEED

“…GO has also been utilized in liquid crystals (LC) for various applications such as supercapacitors, sensors, optical-switching devices, and also graphene oxide-based foam and aerogel for sound absorbers [8][9][10][11]. Graphene oxide liquid crystals (GOLCs), a highly anisotropic fluid consist of the long-range crystal-like ordering of GO.…”

High‐damping polyurethane/hollow glass microspheres sound insulation materials: Preparation and characterization

“…There have been a lot of materials and technologies to reduce the noise. According to the mechanism of noise reduction, it can be classified three categories, sound insulation, 5–8 sound absorption, 9–11 and damping noise reduction 12–14 . Various acoustic materials such as foams, porous particles, hollow microspheres, and fibers exhibited excellent acoustic properties.…”