Thermal insulating, light-weight and conductive cellulose/aramid nanofibers composite aerogel for pressure sensing

• Published in: Carbohydrate polymers Vol. 270; p. 118414
• Main Authors: Wang, Sijie, Meng, Wanyao, Lv, Haifeng, Wang, Zhenxing, Pu, Junwen
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 15-10-2021
• Subjects: Aerogel; Anisotropy; Aramid nanofiber (ANF); Cellulose - chemistry; Electric Conductivity; Gels - chemistry; Nanocellulose; Nanofibers - chemistry; Nylons - chemistry; Polymers - chemistry; Polypyrrole (PPy); Porosity; Pressure sensor; Pyrroles - chemistry; Temperature; Thermal Conductivity; Wearable Electronic Devices; Nanocellulose; Aramid nanofiber (ANF); Aerogel; Pressure sensor; Polypyrrole (PPy)
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2021.118414

Conductive nanocellulose aerogels have attracted significant attention in pressure sensing for wearable devices owing to lightweight, sustainability and good chemical stability. Limited by its flammability and weak mechanical properties, aramid nanofiber (ANF) was designed as reinforcement to overcome the shortcoming mentioned above. Herein, the unidirectional freeze casting method was proposed to fabricate nanocellulose/aramid nanofiber (CA) aerogel. Then, the CA/PPy (CAP) aerogel was obtained by using the oriented structure of CA aerogel as a template for inducing conductive polypyrrole (PPy) in-situ formation inside the composite aerogel. The conductive aerogel with the ordered microstructure exhibited the anisotropic mechanical properties and thermal conductivity. And it could withstand high temperature without any destruction phenomenon. Moreover, the aerogel sensor revealed high strain sensitivity and satisfactory electrochemical performance. Lightweight CAP aerogel with controllable alignment, sensitive sensing property and thermal stability is very promising in pressure sensor under some extreme conditions.
•Multifunctional conductive CNF/ANF/PPy aerogel was successfully prepared.•The aerogel shows anisotropy in the inner structure and the compressive stress.•The aerogel exhibits flame retardant and thermal insulation.•The aerogel with highly sensitive sensing can be developed as pressure sensors.