A self-healing composite film made of cellulose nanocrystals and a polyvinyl acetate copolymer

Xu, Guofan, Laverock, Jude, Koev, Todor T., Khimyak, Yaroslav Z., Diejomaoh, Onajite Abafe, Rochet, Sebastien and Eichhorn, Stephen J. (2025) A self-healing composite film made of cellulose nanocrystals and a polyvinyl acetate copolymer. ACS Applied Polymer Materials, 7 (8). pp. 4982-4991. ISSN 2637-6105

[thumbnail of Xu_etal_2025_ACSAppliedPolymerMaterials]
Preview
PDF (Xu_etal_2025_ACSAppliedPolymerMaterials) - Published Version
Available under License Creative Commons Attribution.

Download (9MB) | Preview

Abstract

A cellulose nanocrystal (CNC)-polyvinyl acetate (PVAc) self-healing composite film was fabricated using a grafting-from approach generating polyvinyl acetate (PVAc) chains on CNC macroinitiators. These grafted-to CNCs were then mixed with bulk PVAc polymer to form a composite. Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and solid-state nuclear magnetic resonance were used to demonstrate the presence of the grafted PVAc chains on the surface of the CNCs. Transmission electron microscopy images revealed the structure of the modified CNCs, which formed closely packed clusters due to the grafted PVAc chains. The thermal properties of the CNCs and their composite films were assessed by using differential scanning calorimetry, determining the appropriate temperature for the healing of the composite film. On this basis, the film was cut into two pieces and rejoined and healed in an oven heated at 40 °C for 6 h. The healed sample was viewed under an optical microscope and electron microscopy, demonstrating the efficacy of the healing process. An array of microindentation tests across the surface of the healed specimen was conducted to quantify stiffness, revealing no detectable differences between the healed and intact regions. This healing was found to only occur for the grafted-to samples and was not evident for the composites made of PVAc and ungrafted CNCs. This work demonstrates that grafting polymer chains onto CNCs and blending these with a bulk polymer are promising approaches for fabricating composite films capable of healing macroscopic fractures.

Item Type: Article
Additional Information: Funding information: S.J.E. and O.A.D. were supported in this research through an EPSRC-funded ED&I Fellowship (EP/V002651/1). T.K. is funded via a UKRI Future Leaders Fellowship awarded to Dr. Matthew Wallace (MR/T044020/1).
Faculty \ School: Faculty of Science > School of Chemistry, Pharmacy and Pharmacology
UEA Research Groups: Faculty of Science > Research Groups > Pharmaceutical Materials and Soft Matter
Depositing User: LivePure Connector
Date Deposited: 02 Jun 2025 14:30
Last Modified: 04 Jun 2025 14:30
URI: https://ueaeprints.uea.ac.uk/id/eprint/99378
DOI: 10.1021/acsapm.5c00219

Downloads

Downloads per month over past year

Actions (login required)

View Item View Item