Characterisation of basic properties of ultrahigh-aspect ratio nanocrystals, and nanopapers, made from cellulose of Cladophora glomerata-algae

Although scattered reports on their various properties exist, there are no in-depth surveys on algal cellulose nanocrystals (CNCs). This is an interesting gap in knowledge, as their dimensions are comparable to those of tunicate cellulose which is generally a staple for long (>1 µm) CNCs. In this study, we aim at presenting algal cellulose from Cladophora glomerata as an accessible and scalable source of CNCs. Cladophora glomerata is relatively easy to grow and has an extremely fast growth rate. Moreover, Cladophora glomerata is naturally abundant in many parts of the world, and the species thrives especially in nutrient polluted waters. Our study systematically investigates the relationship between various reaction conditions in sulfuric acid hydrolysis and the resulting size distributions, surface-charge and rheological properties of algal CNC suspensions produced. The objective is to investigate the suitability of Cladophora glomerata-based CNCs for applications generally envisaged for nanocellulose, including those for cellulose nanofibers. For example, the micron-sized lengths enable the use of these CNCs in cellulose nanopapers – contrary to shorter CNCs based on land plants.