Civil Engineering Reference
In-Depth Information
15.8
Applications of CNCs-Reinforced Biocomposites
Favier
et al.
demonstrated for the i rst time the use of CNCs (extracted from tunicin)
as a nanoi ller in poly(styrene-co-butyl acrylate)(poly (S-co-BuA))-based nanocom-
posites [57, 58] showing the spectacular increment in storage modulus of (poly(S-
co-BuA)) matrix even at low content. Since then, many researchers and scientists
worldwide have become interested in CNCs for applications in diverse i elds due to
their distinctive properties such as ready availability and biodegradability, nanoscale
dimension, unique morphology, high surface area, high mechanical strength, and easy
surface functionalization. In this advancement, CNCs have already been incorporated
into dif erent polymer matrices such as polycaprolactone [185], polysulfonates [186],
cellulose acetate butyrate [187] , carboxymethylcellulose [188] , polyvinyl acetate [189] ,
polypropylene [190], polyvinyl chloride [191], polyethylene [153], polyurethane [192],
poly(vinyl alcohol) [193, 194], polylactic acid [195], soy-protein [196], etc. h e follow-
ing sections highlight some recent studies in research and development of the nano-
composites for potential industrial and biomedical applications.
15.8.1
Industrial Applications
15.8.1.1
Packaging Applications
Swain
et al.
studied the ef ect of various percentages (0-10%) of boron nitride on oxygen,
and the chemical resistant and thermal properties of cellulose/BN nanobiocomposites
for possible applications in insulating and temperature-resistant covering, packaging,
or protective materials. It was revealed that the thermal stability of nanocomposites
was improved as compared to neat cellulose without compromising the oxygen bar-
rier property and has a chemical resistance property against mineral acid and alkali
with little reduction of biodegradability [197]. Li
et al.
reported the multifunctional
and uniform coating (1.5 thick) of CNCs (extracted from cotton linter) on polyethylene
terephthalate (PET), oriented polypropylene (OPP), oriented polyamide (OPA) and
cellophane i lms for better performance for l exible packaging applications. h e CNCs
coating showed excellent anti-fog and remarkable oxygen barrier properties, reducing
the coei cient of friction while maintaining higher transparency (~90%) and low haze
values (3-4%). CNCs-coated PET and OPA showed the best performance among the
investigated coated i lms [198] .
15.8.2
Photocatalytic Materials
Liu
et al.
synthesized TiO
2
/cellulose composite nanomaterials as inorganic/organic
nanocomposites by sol-gel method from the hydrolysis of Ti (OC
2
H
5
)
4
, demonstrating
native CNCs (CNCs produced by acid hydrolysis) as green templates. h e structures
and properties of the composite nanoparticles were characterized with XRD, TEM,
TGA, UV-Vis spectroscopy, and photocatalytic degradation tests. With low loadings of
TiO
2
nanoparticles, the TiO
2
/cellulose composite nanomaterials showed obvious quan-
tum size ef ects and lower band gaps. Under weak UV light irradiation, the composite
nanomaterials revealed promising photocatalytic activity for the photodegradation of
