The development of new materials and coatings provide also new solutions to problems related to acoustic isolation on architecture, vehicles or aircrafts. Fibrous materials have particularly interesting features for acoustic barriers, as they are usually light, resistant and adaptable to diverse geometries . The sound absorption coefficient is calculated as the quotient between the acoustic energy absorbed and incident on a material. It can be obtained as described by the International Standard UNE-EN ISO 10534-2:2002.
The material of the electrospinning fibers is a key parameter on the resulting acoustic barrier. Studies have described PVC and polyvinylpyrrolidone (PVP) fibers as good isolating materials. PVC and PVP electrospinning fibers absorption coefficient for some frequency ranged are better compared to melamine foams, conventionally used as sound absorber . PVC and PVP fibers are also lighter than melamine foams, so applications in aerospace and aircraft industry are very promising . Electrospun nanofibers provide a big, porous surface area that increases the contact with sound waves. This facilitates the dissipation of sound energy by friction and vibration of the electrospinning fibers.
Moreover, this sound energy absorbed by the electrospinning fibers can be converted to electric potential by piezoelectric effect. PVDF piezoelectric electrospinning scaffolds have been successfully obtained to absorb sound, particularly in the low-frequency region, and transforming it into electric energy . Electrospinning fibers can be also used to fabricate acoustic sensors. Chen et al.  described a flexible sensor based on lead zirconate titanate nanofibers with 50 to 120 nm diameter, that were aligned in between interdigitated electrodes. The piezoelectric voltage constant of the plead zirconate titanate, the flexibility and strength of the nanofibers provided high performance sensors for monitoring small, curved structures, or even living cells .
 J Alba, R Del Rey, L Berto, C Hervás, Use of textile nanofibers to improve the sound absorption coefficient of drilled panels for acoustic applications, Acoustics 2012, 2012
 Asmatulu, R., Khan, W. S., & Yildirim, M. B. (2009). Acoustical properties of electrospun nanofibers for aircraft interior noise reduction.
 Wu, C. M., & Chou, M. H. (2016). Sound absorption of electrospun polyvinylidene fluoride/graphene membranes. European Polymer Journal, 82, 35-45.
 Chen, X., Guo, S., Li, J., Zhang, G., Lu, M., & Shi, Y. (2013). Flexible piezoelectric nanofiber composite membranes as high performance acoustic emission sensors. Sensors and Actuators A: Physical, 199, 372-378.
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