Polyvinylpyrrolidone (PVP)/ Graphene based soundproofing materials through electrospinning

In this work, new light (density=63 Kg/m3) soundproofing materials were obtained through electrospinning of high molecular weight (1300 KDa) polyvinylpyrrolidone (PVP) (15% w/w) and graphene (from 0,03 to 7.68 mg mL-1) alcoholic suspensions. The mats possess interesting sound absorption properties in the frequency range (200-800 Hz) where traditional soundprrofing materials do fail. The sound absorbers were obtained in the form of blankets of thin disks of 10 cm diameter. For a given set of disks (from a minimum of 6) the sound absorption coefficient αa changes, in the frequency range 200-1600Hz, following a bell-like curve with a maximum (close to 1.0) that shifts to lower frequencies the higher the piled disks number (and mass). The experimental results suggest that sound energy dissipation occurs primarily because of resonance of the sound wave with the natural frequency of vibration of the disks pile (acting as a membrane). The paper shows how the presence of graphene affects the acoustic properties.