Oral Presentation Royal Australian Chemical Institute National Congress 2026

Single-step grafting of a thermoresponsive RAFT polymer from nanocellulose by radical decarboxylation (136590)

Gianluca Vidali 1 2 , David Joram Mendoza 2 3 4 , Cameron Bentley 1 , Alasdair I. McKay 5 , Vikram Singh Raghuwanshi 2 3 6 , Jitendra Mata 7 8 , Gil Garnier 2 3 , Joel F. Hooper 1 2
  1. Chemistry, Monash University, Clayton, Victoria, Australia
  2. Bioresource Processing Research Institute of Australia (BioPRIA), Monash University, Clayton, Victoria, Australia
  3. Department of Chemical and Biological Engineering, Monash University, Clayton, Victoria, Australia
  4. Institute of Biological Control, De La Salle University, Biñan, Laguna, Philippines
  5. Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Queensland, Australia
  6. Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Queensland, Australia
  7. Australian Centre for Neutron Scattering (ACNS), Australian Nuclear Science and Technology Organization (ANSTO), Lucas Heights, NSW, Australia
  8. Chemistry, University of New South Wales, Sydney, NSW, Australia

Nanocellulose-polymer composites are emerging as advanced materials with outstanding mechanical, thermal, and chemical properties, driving innovation across biomedical, environmental, and industrial applications. This work introduces a novel, efficient method for synthesizing thermoresponsive TEMPO-oxidized cellulose nanofiber (TOCNF) and poly(N-isopropylacrylamide) (PNIPAM) conjugates via silver-mediated RAFT polymerization. In contrast to traditional techniques requiring prior modification of nanocellulose with RAFT agents, this approach enables surface-initiated polymerization through Ag-mediated radical decarboxylation of TOCNF. The radicals generated on TOCNF act as active sites for the polymerization of NIPAM, forming robust C–C bonds between the cellulose nanofibers and the grafted polymer.

This green, one-step, one-pot reaction, performed primarily in aqueous conditions and under mild temperatures, yields thermoresponsive PNIPAM-g-CNF hydrogels with tunable molecular weights, high grafting density, and quite narrow polydispersity. The presence of RAFT agents as polymer end-groups further allows for end-group modification, facilitating the synthesis of block copolymers and providing a versatile platform to customize material properties. SANS analysis of the materials provides a clear model to explain the effect of the polymer degree of polymerization on the thermoresponsive and gelation properties of PNIPAM-g-CNF, where a lower degree of polymerization results in an ordered assembly of bundled fibers above the gelation temperature.

This approach enables efficient polymer grafting without requiring extensive modifications to the nanocellulose, thus lowering chemical waste. The versatility of this method in tailoring material properties while adhering to green chemistry practices underscores its potential for developing sustainable, high-performance materials for addressing pressing industrial and environmental challenges.1

 

 

  1. Vidali, G.; Mendoza, D. J.;  Bentley, C.;  McKay, A. I.;  Raghuwanshi, V. S.;  Mata, J.;  Garnier, G.; Hooper, J. F., Single-Step Grafting of a Thermoresponsive RAFT Polymer from Nanocellulose by Radical Decarboxylation. ACS Polymers Au 2025.

 

  1. Vidali, G.; Mendoza, D. J.; Bentley, C.; McKay, A. I.; Raghuwanshi, V. S.; Mata, J.; Garnier, G.; Hooper, J. F., Single-Step Grafting of a Thermoresponsive RAFT Polymer from Nanocellulose by Radical Decarboxylation. ACS Polymers Au 2025.