Displaying high aspect ratios, cellulose nanofibres (CNFs) form highly entangled fibrillar networks already at low concentrations. When freeze-dried, wet CNF networks are turned into highly porous materials often referred to as CNF aerogels. These low-density networks benefit from the unique properties of the CNFs, exhibiting high specific surface areas, excellent water absorbency and good chemical stability. However, the preparation of such aerogels suffers from both the high cost and the batch-wise nature of the freeze-drying process commonly used, and often relies on harsh crosslinking chemistries. In this study we demonstrate a novel, green and efficient method to prepare crosslinked low-density materials from wet CNF networks. Based on a combination of freezing (-18 °C), solvent exchange and evaporation steps, this procedure could enable a fast and large-scale production of CNF aerogels. The low-density materials were successfully crosslinked by adding alginate to the CNF networks under controlled ionic conditions. The CNF and alginate mixtures present good flow properties and high viscosity and are hence attractive for 3D printing applications. In the present work, we demonstrate the possibility of preparing aerogels of virtually any shape by combining 3D printing with our novel method procedure (Fig. 1). By possessing both a high wet-stability and a high specific surface area, these green materials could be appealing substrates for designing and preparing advanced materials in fields such as organic electronics or tissue engineering.

3D printable nanocellulose aerogels via a green crosslinking approach and a facile evaporation procedure

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.