NANOCELLULOSE

Wood pulp can be converted into nanoparticles on the scale of 100-800nm in length and 5-10nm in diameter through a variety of processes and reaction conditions. These nanoparticles called cellulose nanocrystals (CNCs) hold the promise of a futuristic forest products industry, with CNCs targeted for a diverse range of applications such as composite materials for helicopter parts, tissue engineering scaffolds for bone repair, reinforced cement for bridges, iridescent films for security papers, supercapacitors for energy storage systems, and drug delivery systems for human health. This exciting vision requires additional research to facilitate CNCs for these unique markets, through chemical modification and surface functionalization of nanocrystals. One of the closest competitors to CNC technologies is nanofibrillated cellulose (NFC), which has been incorporated into two different commercial products— adult diapers and specialty inks. NFC barrier properties were exploited to address the problem of odor retention, while rheological modification of the ink addressed ink blot issues. Many NFC materials are produced using 2,2,6,6-Tetramethyl-1-piperidinyloxy (TEMPO) mediated oxidation of cellulose pulp, converting C6 surface hydroxyls into carboxylic acid groups. The advantage to this material is that carboxylic acid groups serve as “handles” that can be further modified with a number of chemistries to enable functionalization for many applications.