A simple and facile method for depositing multiwall carbon nanotubes (MWCNTs) onto the surface of
naturally occurring short jute fibers (JFs) is reported. Hierarchical multi-scale structures were formed
with CNT-networks uniformly distributed and fully covering the JFs (JF–CNT), as depicted by the scanning
electron microscopy (SEM) micrographs. The impact of these hybrid fillers on the mechanical properties
of a natural rubber (NR) matrix was systematically investigated. Pristine JFs were cut initially to an average
length of 2.0 mm and exposed to an alkali treatment (a-JFs) to remove impurities existing in the raw
jute. MWCNTs were treated under mild acidic conditions to generate carboxylic acid moieties. Afterward,
MWCNTs were dispersed in an aqueous media and short a-JFs were allowed to react with them. Raman
spectroscopy confirmed the chemical interaction between CNTs and JFs. The JF–CNT exposed quite
hydrophobic behavior as revealed by the water contact angle measurements, improving the wettability
of the non-polar NR. Consequently, the composite interfacial adhesion strength was significantly
enhanced while a micro-scale ‘‘mechanical interlocking’’ mechanism was observed from the
interphase-section transmission electron microscopy (TEM) images. SEM analysis of the composite fracture
surfaces demonstrated the interfacial strength of NR/a-JF and NR/JF–CNT composites, at different
fiber loadings. It can be presumed that the CNT-coating effectively compatibillized the composite structure
acting as a macromolecular coupling agent. A detailed analysis of stress-strain and dynamic mechanical
spectra confirmed the high mechanical performance of the hierarchical composites, consisting
mainly of materials arising from natural resources.