Page 42 - New Cloth Market November 2022 Digital Edition

Chitosan-Based Sustainable Textile Technology: Process, Mechanism, Innovation & Safety

Physical, chemical, and mechanical electrospinning process [33]. The metal and uniform surfaces. The main
characters of chitosan fibers and the ions also help to break down the intra- advantage of blending of chitosan and
ability to build in different forms and intermolecular hydrogen bonds and agarose is the production of nanosized
facilitate chitosan nanofibers for the reduce the viscosity of chitosan fibers. The achieved fiber diameter is
filtration process, for example, metal solution that would enhance the chain 520 ± 35 nm and 140 ± 9 nm for using
and dyes separation from water [20, entanglements. As a result, lower 30 and 50% agarose, respectively.
21], capturing of virus in air [22], etc. number of beads and reduced diameter Besides, the pure chitosan fibers from
In addition, the technological of fibers are obtained from chitosan electrospinning process exhibit around
developments in textile processing electrospinning process [33]. Some 1.76 ± 0.59 µm in diameter [38].
associated with chitin and chitosan processes of chitosan blends and
Poly lactic-co-glycolic acid (PLGA)-
would impact on reinforcing microfibers mechanical properties have been
chitosan-PVA blends
composite [23], dressing for wound skin demonstrated below.
[15, 24–26], carrying and delivering The PVA and chitosan are dissolved
Nylon-6/chitosan blends fiber
drugs [22, 27], tissue engineering [15, in 2 wt.% acetic acid separately and
28–30], vascular grafts [31], etc. Two solvents, 1,1,1,3,3,3- blends at a ratio of 60:40. The mixture
hexafluoroisopropanol (HFIP) and is used for the electrospinning process.
Chitosan blends for electrospinning
formic acid at a ratio of 90/10, have Besides, PLGA of 6 wt.% is dissolved
process
been used to dissolve nylon-6 and in a mixture of solvents, tetrahydro-
Apart from the pure chitosan chitosan for the electrospinning furan (THF) and N,N-dimethylforma-
processing, many studies have process. The total weight of polymer mide (DMF). The electrospinning
reported on mixtures of chitosan with has been maintained 6% by varying process is modified by adding an extra
different polymers such as polyvinyl the concentrations of both polymers. tip or syringe parallel to another tip for
alcohol (PVA) [32], polyacrylamide [33, The similar electrospinning process holding two polymer solutions
34], polyethylene oxide (PEO), has been operated at room temperature separately. The collector collects the
polyacrylonitrile (PAN) [35], [37]. The properties of the blend fibers spinning fibers from both tips. In this
caprolactone [14], and Zein (an depend on the blending weight ratio. process, chitosan/PVA and PLGA
agrobased protein) [36] to modify the The increased amount of chitosan solutions are used separately in these
chitosan solution property and facilitate increases the functional sites for tips and run the electrospinning
the spinnability by easy flowing through capturing water molecules. A unique process. The tensile strength values
the capillary tip. For example, the molecular interaction between nylon-6 of three different electrospun
viscosity of chitosan solution and chitosan is formed due to nanofibers/PLGA, chitosan/PVA, and
decreases with the increasing amount developing a hydrogen bond which PLGA-chitosan/PVA-achieved by
of PEO. The main reasons for the affects the mechanical property of the electrospun are 7.3, 4.3, and 2.6 MPa,
change in viscosity is the reduction of blend fibers. The tensile strength and respectively. The reason behind the
intra- and intermolecular attraction crystallization behavior decrease due result is no interaction present between
among the chitosan chains and the to the formation of an amorphous PLGA and chitosan/PVA. Besides,
formation of new bonding of PEO with polymer during the electrospinning PLGA-chitosan/PVA and chitosan/
the backbone of chitosan. The process. For example, 25% of chitosan PVA nanofibers are crosslinked
presence of PEO on chitosan structure in the blends shifts the melting point separately using 25% glutaraldehyde.
interferes the intra- and intermolecular at 258.1°C, while pure nylon-6 exhibits The tensile strength of crosslinked
association, while new hydrogen bonds the temperature at 268°C [37]. PLGAchitosan/PVA is found higher
are formed between –OH group of Chitosan-agarose blend fibers compared to uncrosslinked nanofibers.
chitosan and water. It results in a In contrast, the crosslinked chitosan/
drastic reduction in the viscosity of Chitosan and agarose, one kind of red PVA nanofibers have lower tensile
chitosan solution [15]. Furthermore, algae, are dissolved in a mixture of strength than that of uncrosslinked
PVA also facilitates interaction with solvents, trifluoro-acetic acid (TFA) nanofibers. In the case of crosslinked
chitosan in molecular levels that restrict and dichloromethane (DCM). The PLGA-chitosan/PVA, some bonds are
the intra- and intermolecular interaction polymer has been maintained at 7%, formed after crosslinking with
among chitosan chains and provide a while the solvent ratio between TFA and glutaraldehyde [39].
better spinnable solution [16]. DCM is 7:3. In the electrospinning
process, the operating electrostatic Chitosan-based textile processing
Moreover, inorganic nanoparticles such potential is 15 kV/12 cm and the
Chitosan: a sizing and desizing
as sodium chloride, potassium solution flow rate is 0.5 ml/h. The
agent for textile pretreatment
chloride, or ions such as calcium and blending contents of 30 and 50%
iron are used in doping chitosan in the agarose provide fibers with smooth Sizing is the conventional process of

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