Water and humidity-induced shape memory cellulose nanopaper with quick response, excellent wet strength and folding resistance

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2020-07, Vol.392, p.123673, Article 123673
• Main Authors: Wu, Meiyan, Sukyai, Prakit, Lv, Dong, Zhang, Fang, Wang, Peidong, Liu, Chao, Li, Bin
• Format: Article
• Language: English
• Subjects: Cellulose nanofibrils; Cellulose nanopaper; Chitosan; Humidity sensitivity; Shape memory
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2019.123673

[Display omitted] •A robust and water-induced shape memory CNP was prepared with CNFs and CS.•Fast response to water of the CNP is due to synergistic hydration of CS and CNFs.•The final CNP shows excellent wet strength and folding endurance.•The final CNP exhibits amazing barrier and antibacterial properties.•The final CNP has potential use in humidity sensor, packaging, medicine, etc. Water-induced shape memory polymers (SMPs) are the desired candidates for the uses in the fields of surgical operation, smart textile, and aerospace. However, most of water-induced SMPs are non-biodegradable petroleum-based polymers, and a quick response to water of SMPs is usually accompanied with the loss of wet strength due to the over hydration. To address this issue, in this work, a water resistant cellulose nanopaper (CNP) was firstly prepared with the cellulose nanofibrils (CNFs) produced by formic acid hydrolysis, and then the obtained CNP was modified via immersing in chitosan (CS) for the preparation of a robust CNP with quick water and humidity responses. Results showed that the original shape of the modified CNP after folding could immediately respond to water (