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85.2% strain rate was almost 2.5-fold larger than that of the pure PAM hydrogel because
of enhanced interfacial interaction of well-dispersed CNCs in PAM matrix [60]. h ey
concluded that such economical CNC-reinforced nanocomposite hydrogels, which
combines high biocompatibility (both matrix and nanoi llers) with high strength, can
be potentially used as both traditional bone-defect repair and bone tissue engineer-
ing. Consequently, the application potential of biomass cellulose nanocrystals used as
value-added products will be expanded.
5.5.2
Electrically Active Paper
A novel composite paper was fabricated by Luong
et al
. [61] out of nanoi brillated cel-
lulose (NFC) and Polyaniline (PANi) through
in-situ
polymerization technique. h e
synthesized materials exhibited high electrical conductivity and good mechanical char-
acteristics and can be explored for various electrically active application areas.
h ey developed Polyaniline-based aqueous suspensions containing a variety of poly-
aniline (PANi) contents ranging between 5 and 80 wt% through
in-situ
polymerization
of aniline in a nanocellulose suspension. A suspension of high aspect ratio nanoi -
brillated cellulose (NFC) was prepared by combining enzymatic hydrolysis with high
mechanical shearing. Aniline monomer was dissolved in NFC suspensions in dif er-
ent amounts and then
in-situ
oxidative polymerization was carried out, schematically
shown in Figure 5.5.
h ey studied the morphology of the
in-situ
formed NFC/PANi composites by AFM
shown in Figure 5.6b. h e AFM image showed that the PANi particles were irregular in
Adding APS oxidant
solution
Dissolving Anitine in
HCl solution
Adding to NFC
suspension
(i)
(ii)
(iii)
Anitine +
HCl
Cellulose ibril
Cellulose ibril coated with
PANi macromolecules
(i) Absorption
(ii) In situ polymerization
(iii) Washing and solvent
evaporation
NFC/PANi composite
formed by vacuum iltration
or casting
(
a
)
(
b
)
Figure 5.5
Schematic showing the preparation of NFC/PANi composite paper through
in-situ
polymerization of aniline monomers on nanocellulose i brils and b) NFC, PANi and NFC/PANi
composite suspensions. Reproduced from [61] with permission of Elsevier.
