Innovative two-phase air plasma activation approach for green and efficient functionalization of nanofibrillated cellulose surfaces from wheat straw

摘要: Abstract A green, facile two-phase air plasma/mild alkaline (TPAP/MA) pretreatment approach was developed for efficient production of carboxyl- and amino-functionalized nanofibrillated cellulose derivatives (TO-NFC NFC-Amine, respectively) from wheat straw (WS). Herein, TPAP activation performed stepwise through two-scissions at the level WS fibers and, subsequently, WS-cellulosic combined with mild NaOH pretreatment. The pretreated substrates showed altered surface-characterizations a gradual-additional aldehyde, carboxyl, reactive hydroxyl groups according to time, all which promoted subsequent isolation, nanofibrillation, functionalization reactions. TPAP/MA accompanied by TEMPO-oxidization protecting-group-free amidation revealed high carboxyl amine contents TO-NFC NFC-Amine (up 2.55 mmol COO−/g 2.20 mmol NH2+/g, DSs = 1.02 1.42, respectively), leading 5.9- 6.5-fold increase in pH-responsive swelling ratios their nanohydrogels compared conventional substrates. Considering feasibility green aspects, 90 s-TPAP/MA produced nanofibrillation yields 73.4% 97.6%, respectively. Furthermore, this consumed only 158.5 kWh/t 90.4% reduction total energy consumption relative functionalized NFC process baseline process, demonstrating an energetically friendly route significant potential be scaled industrial-level.