Mi HY, Jing X, Politowicz AL, Chen E, Huang HX, Turng LS (2018) Highly compressible ultra-light anisotropic cellulose/graphene aerogel fabricated by bidirectional freeze drying for selective oil absorption. Song JW, Chen CJ, Yang Z, Kuang YD, Li T, Li YJ, Huang H, Kierzewski I, Liu BY, He SM, Gao TT, Yuruker SU, Gong A, Yang B, Hu LB (2018) Highly compressible, anisotropic aerogel with aligned cellulose nanofibers. Gavillon R, Budtova T (2008) Aerocellulose: new highly porous cellulose prepared from cellulose-naoh aqueous solutions. Han YY, Zhang XX, Wu XD, Lu CH (2015) Flame Retardant, heat insulating cellulose aerogels from waste cotton fabrics by in situ formation of magnesium hydroxide nanoparticles in cellulose gel nanostructures.

Zhou ZH, Yang YB, Han YY, Guo QQ, Zhang XX, Lu CH (2017) In situ doping enables the multifunctionalization of templately synthesized nanocomposites. Yuan B, Zhang JM, Mi QY, Yu J, Song R, Zhang J (2017) Transparent cellulose-silica composite aerogels with excellent flame retardancy via an in situ sol-gel process. Jimenez-Saelices C, Seantier B, Cathala B, Grohens Y (2017) Spray freeze-dried nanofibrillated cellulose aerogels with thermal superinsulating properties.

Paakko M, Vapaavuori J, Silvennoinen R, Kosonen H, Ankerfors M, Lindstrom T, Berglund LA, Ikkala O (2008) Long and entangled native cellulose I nanofibers allow flexible aerogels and hierarchically porous templates for functionalities. Li DK, Chang DQ, Liu BL (2020) Diffuse sound absorptive properties of parallel-arranged perforated plates with extended tubes and porous materials. Zheng WG, Huang QB, Li SD, Guo ZY (2011) Sound Absorption of hybrid passive-active system using finite flexible micro-perforated panels. Tzivian L, Jokisch M, Winkler A, Weimar C, Hennig F, Sugiri D, Soppa VJ, Dragano N, Erbel R, Jockel KH, Moebus S, Hoffmann B, Heinz Nixdorf Recall Study G (2017) Associations of long-term exposure to air pollution and road traffic noise with cognitive function-an analysis of effect measure modification. Tzivian L, Winkler A, Dlugaj M, Schikowski T, Vossoughi M, Fuks K, Weinrnayr G, Hoffmann B (2015) Effect of long-term outdoor air pollution and noise on cognitive and psychological functions in adults. Goines L, Hagler L (2007) Noise pollution: a modern plague. Seidman MD, Standring RT (2010) Noise and quality of life. Sakthivel S, Kumar BS (2021) Studies on influence of bonding methods on sound absorption characteristic of polyester/cotton recycled nonwoven fabrics. Therefore, the CAs treated with directional freezing has good prospects for application in the field of sound absorption. More importantly, directional cellulose aerogel in this study has good mechanical properties, with a compressive stress of 0.35 MPa at 70% strain.

cm −3), high porosity (89.32%) and good thermal stability.In addition, CAs prepared in this study have low density (0.0554 g The sound absorption coefficient of directional cellulose aerogel reached 0.88 at 4500 Hz. CAs with regularly distributed and axially open porous structure were prepared to improve the sound-absorbing performance to meet application requirements. In this study, the cellulose hydrogels were obtained by dissolving cotton staple as the main material, and the cellulose hydrogel was treated with directional freezing to solve the problem of irregular distribution and coexistence of open and closed pore structures in the traditional cellulose aerogels (CAs). With noise pollution and environmental pollution becoming more and more serious, it is very urgent to develop a kind of green, recyclable and degradable sound-absorbing material.

Carbon nanotubes aerogel