The Critical Roles of Water in the Processing, Structure, and Properties of Nanocellulose

Abstract

The cellulose industry depends heavily on water owing to the hydrophilic nature of cellulose fibrils and its potential for sustainable and innovative production methods. The emergence of nanocellulose, with its excellent properties, and the incorporation of nanomaterials have garnered significant attention. At the nanoscale level, nanocellulose offers a higher exposure of hydroxyl groups, making it more intimate with water than micro-and macroscale cellulose fibers. Gaining a deeper understanding of the interaction between nanocellulose and water holds the potential to reduce production costs and provide valuable insights into designing functional nanocellulosebased materials. In this review, water molecules interacting with nanocellulose are classified into free water (FW) and bound water (BW), based on their interaction forces with surface hydroxyls and their mobility in different states. In addition, the waterholding capacity of cellulosic materials and various water detection methods are also discussed. The review also examines water-utilization and water-removal methods in the fabrication, dispersion, and transport of nanocellulose, aiming to elucidate the challenges and tradeoffs in these processes while minimizing energy and time costs. Furthermore, the influence of water on nanocellulose properties, including mechanical properties, ion conductivity, and biodegradability, are discussed. Finally, we provide our perspective on the challenges and opportunities in developing nanocellulose and its interplay with water.

Chitinous Bioplastic Enabled by Noncovalent Assembly

“…Based on the mechanism for the water-mediated molecular mobility of the CTBP, we attempted to propose a waterinduced hydro-setting strategy to transform the CTBP-6 sheets into desired shapes (right angle, helix, and arc) by a waterwetting and air-drying process (Figure 4l,m). 58 The relatively weak chitin-TA noncovalent cross-links within the CTBP could effectively act as dynamic bonding under water mediation. The chitin-TA cross-links were easier to disrupt by the water, thus affording the chitin molecule a higher mobility, eventually enabling a higher hydroplasticity.…”

“…The small piece of CTBP sheet (4 mm in width and 80 μm in thickness) even could bear 1 kg, indicating superior mechanical properties (Figure 1c). Moreover, water could serve as the chitin-TA noncovalent cross-link mediator 58 among the chitin chains to endow the CTBP with excellent hydroplastic (water-induced shaping) performance. Thus, the CTBP could be shaped into the desired structure, yielding the "plane" shape as shown in Figure 1d.…”

Recent Advances in Biopolymer-Based Hydrogel Electrolytes for Flexible Supercapacitors

“…Moreover, the delignified wood can also be used as a gel scaffold to control the swelling behavior and enhance the mechanical properties of the hydrogels in salt solutions. Its porous structure also facilitates the transport of electrolyte ions . Similarly, Gao et al combined quaternized gelatin with poly­(acrylic acid- co -acrylamide) gelled in situ on a flexible wood scaffold.…”

Gel polymer electrolytes for rechargeable batteries toward wide-temperature applications

“…, bacteria, wood, bamboo, and grass), high ionic conductivity, satisfactory mechanical strength and good freezing tolerance, creating a range of possibilities for developing functional, inexpensive, safe, and environment-friendly GPEs. 230,418–420 We expect that their applications could be extended to wide-temperature scenarios and more rechargeable battery systems.…”