Role of nanocellulose geometric structures on the properties of green natural rubber composites
Milanta Tom
, Sabu Thomas, Bastien Seantier, Yves Grohens, Mohamed Pulikaparambil Kochaidrew, Ramakrishnan Subramanian, Tapas Ranjan Mohanty, Henri Vahabi, Hanna Joseph Maria, Jibin Keloth Paduvilan, Martin George Thomas
, Sabu Thomas, Bastien Seantier, Yves Grohens, Mohamed Pulikaparambil Kochaidrew, Ramakrishnan Subramanian, Tapas Ranjan Mohanty, Henri Vahabi, Hanna Joseph Maria, Jibin Keloth Paduvilan, Martin George ThomasVol. 18., No.6., Pages 638-655, 2024
DOI: 10.3144/expresspolymlett.2024.47
DOI: 10.3144/expresspolymlett.2024.47
Corresponding author: Sabu Thomas 
GRAPHICAL ABSTRACT
ABSTRACT
The augmented demand for
sustainable nanocomposites has paved the way to explore naturally derived
materials. Nanocellulose, with its bountiful sources and inherent properties,
ranks top in the list of biofillers with a perspective of reducing the carbon
footprint. A systematic study is required to understand the reinforcing effect
of various types of nanocellulose. In the present work, we selected three types
of nanocellulose, i.e.,
cellulose nanocrystal (CNC), cellulose nanofiber (CNF) and microfibrillated
cellulose (MFC), to investigate the effect of geometrical structure on the
properties of unvulcanized natural rubber (NR). Incorporating these fillers
improved the tensile strength and modulus of natural rubber films significantly
through reinforcement via filler network structure. The reinforcing effect of
CNF was found to be higher compared to CNC and MFC, where an increase of 3.85
MPa in tensile strength from the neat sample was obtained. More uniform
dispersion was evident through transmission electron microscopy, atomic force
microscopy and Raman imaging for CNF in the rubber matrix. The structural
properties were determined using Raman spectra and X-ray diffraction. The rheological
studies revealed a good interaction between filler and NR. The work presented
comprehensively compares different types of nanocellulose as reinforcing filler
in NR matrix, which will help the researchers select an ideal type for their
specific application and, thus, the proper usage of renewable resources,
leading to sustainability and a circular economy.
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