Nanocellulose hybrid systems: carriers of active compounds and aerogel/cryogel applications

Aerogels and cryogels based on hybrid nanocellulose systems have been studied to improve physical-chemical and mechanical properties suitable for such applications as tissue engineering, food packaging, cosmetics, and others. The main properties of these porous cellulose materials are water absorption, water retention, biocompatibility, and mechanical properties. Both cellulose nanofibrils (CNFs) and cellulose nanocrystals (CNCs) can be used to produce hybrid systems. The association of CNCs and CNFs with other polymers leads to physical and chemical cross-linking, improving their properties. In our research group, chitosan nanoparticles (ChNPs) were recently used to form the complex ChNP-CNC for folic acid carrying. This chapter summarizes how hybrid systems containing CNCs and CNFs are produced and their possible application in aerogels/cryogels. The properties of materials composed by the association of nanocelluloses (CNFs and CNCs) with other matrices were summarized in comprehensible tables and a case study using ChNP-CNC-based cryogels was presented.