Tailoring Aerogel-Like Surface Characteristics of Bacterial Cellulose by Electron Beam Irradiation-Induced Decomposition

Abstract

Bacterial cellulose (BC) is a sustainable material renowned for its three-dimensional nanofibrous structure, offering diverse applications in medical, textile, leather, and other industries. However, developing effective modification technologies for BC has presented contemporary challenges regarding sustainability and efficiency, both in academia and industry, with electron beam irradiation (EBI) emerging as a promising, fast, scalable, and sustainable solution. This study focuses on leveraging EBI-induced decomposition on hydrated BC nanofibrous networks to generate an aerogel-like surface morphology post-dehydration, offering a chemical-free modification method. Investigating the effects of EBI across various absorbed doses (0, 10, 50, and 100 kGy) on BC properties aims to lay the groundwork for employing EBI in BC modifications. Successful fabrication of BC with aerogel-like surface morphology at an absorbed dose of 50 kGy resulted in fascinating findings in terms of applications, including decreased tensile strength (7.7 ± 1.3 MPa), increased bending modulus (6062.7 ± 1574.8 MPa), partially reduced thermal stability (primary peak at approximately 320 ± 4 °C and a new secondary peak at approximately 238 ± 5 °C), slightly decreased crystalline index (79.3 ± 1.0%), decreased moisture regain (5.6 ± 0.9%), and notably enhanced thermal insulation (reduced maximum heat flux of 0.057 ± 0.004 W/cm²). Additionally, EBI treatment induced oxidation, slightly increasing oxygen content and causing a yellowing effect on BC while preserving most functional groups and the hydrophilicity of BC. The adoption of EBI provides a premise for future studies and applications in BC functionalization, utilizing advanced and sustainable technology for mass production and sustainable applications of BC-based products.

Graphical Abstract