Projects per year
Abstract
A family of thermoresponsive poly(N-isopropylacrylamide) [PNIPAM]-grafted cellulose nanofibers (CNFs) was synthesized via a novel silver-promoted decarboxylative polymerization approach. This method relies on the oxidative decarboxylation of carboxylic acid groups to initiate free radicals on the surface of CNFs. The polymerization reaction employs relatively mild reaction conditions and can be performed in a one-step, one-pot fashion. This rapid reaction forms a C─C bond between CNF and PNIPAM, along with the formation of free polymer in solution. The degree of functionalization (DF) and the amount of PNIPAM grafted can be controlled by the Ag concentration in the reaction. Similar to native bulk PNIPAM, PNIPAM-grafted CNFs (PNIPAM-g-CNFs) show remarkable thermoresponsive properties, albeit exhibiting a slight hysteresis between the heating and cooling stages. Grafting PNIPAM from CNFs changes its cloud point from about 32 to 36 °C, influenced by the hydrophilic nature of CNFs. Unlike physical blending, covalently tethering PNIPAM transforms the originally inert CNFs into thermosensitive biomaterials. The Ag concentration used does not significantly change the cloud point of PNIPAM-g-CNFs, while the cloud point slightly decreases with fiber concentration. Rheological studies demonstrated the sol-gel transition of PNIPAM-g-CNFs and revealed that the storage modulus (G′) above cloud point increases with the amount of PNIPAM grafted. The novel chemistry developed paves the way for the polymerization of any vinyl monomer from the surface of CNFs and carbohydrates. This study validates a novel approach to graft PNIPAM from CNFs for the synthesis of new thermoresponsive and transparent hydrogels for a wide range of applications.
Original language | English |
---|---|
Pages (from-to) | 1610–1621 |
Number of pages | 12 |
Journal | Biomacromolecules |
Volume | 23 |
Issue number | 4 |
DOIs | |
Publication status | Published - 18 Jan 2022 |
Projects
- 1 Finished
-
ARC Research Hub for Processing Lignocellulosics into High Value Products
Garnier, G., Batchelor, W., Simon, G., Haritos, V., Patti, A., Saito, K., Griesser, H., Paull, B., Tanner, J., Spinnler, H., Allais, F., Richardson, D., Mackay, A., Carter, S., Faltas, R., Edye, L., Hendriks, D., Karmakar, N., Bhattacharya, S. & Hawe, N.
Monash University – Internal University Contribution, Monash University – Internal Faculty Contribution, Monash University – Internal Department Contribution, Paper Australia Pty Ltd, Leaf Resources Pty Ltd, Department of State Growth (Tasmania), University of Tasmania, University of South Australia, Agro Biotechnologies Industrielles, Visy Industries Australia Pty Ltd (trading as Visy Industries), Norske Skog Paper Mills (Australia) Pty Ltd, Orora Limited (trading as AMCOR Australia)
10/01/18 → 31/12/24
Project: Research
Equipment
-
X-ray Platform (MXP)
Ji Sheng Ma (Manager)
Materials Science & EngineeringFacility/equipment: Facility