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3 Chitin
3.7.10 Papermaking
While their wastewater treatment application already makes chitin useful to the papermaking industry in treatment of wastewater from papermaking, chitin/chitosan has
further applications in this industry beyond water treatment, and this includes surface
coating, dye fixation and paper strengthening. Antibacterial and greaseproof paper
are also in the horizon of future applications of chitosan in the paper industry.
In the wet end application, chitosan and other chitosan derivatives find use as
retention and drainage agents. They act as flocculants and coagulants causing the
aggregation of fine particles and liquids to aid the separation process. The mechanism by which they do this is through electrostatic attraction facilitated by the
attraction between the amino and hydroxyl group and the fine particles thanks to the
polycationic nature of chitosan.
Between cellulose fibers exist voids due to the repulsive force between like
charges. Due to its excellent film-forming property, chitosan covers this void between
the fibers, making for a stronger paper. Chitosan and chitosan derivatives can be
applied as coatings on paper. This is aided by its affinity for cellulose. Chitosan
coatings give antimicrobial properties and improve water vapor and oxygen barrier
properties of the paper. Such papers find use in food packaging and medical uses.
Further application of chitosan in paper production includes its use in dye fixation
for improving the dyeing of paper and chitosan nanoparticle derivatives used in
producing transparent paper (Song et al. 2018).
3.7.11 Electronics
Ubiquity of chitin is further demonstrated by its applicability in electronics. Flexible
electronics, photovoltaic cells and biomedical sensors are some of the applications
which employ chitin. Most of these are using chitin in the deacetylated form (chitosan). The electronics industry is one that makes use of a large amount of polymers, from cable coatings to casings to flexible substrates for photovoltaic cells.
While many of the applications of chitin involve the deacetylated form, chitosan,
some recent applications have explored chitin nanoparticles, for example, in use as
biodegradable, eco-friendly flexible substrates for light-emitting diodes (Jin et al.
2016).
Flexible electronics have become desirable for lightweight, low-cost electronics
such as screens and photovoltaic cells. Being able to process these electronics on
flexible substrates allows for mass reproducible roll to roll processing techniques
at low temperatures such as solvent casting and more portable designs. Recently,
plastics such as polyethylene terephthalate and polyethylene have been used for
such. Even better would be biodegradable polymers for such applications. Chitin
and chitosan and their derivatives have demonstrated suitability for such applications
(Triyana et al. 2018).
3 Chitin
3.7.10 Papermaking
While their wastewater treatment application already makes chitin useful to the papermaking industry in treatment of wastewater from papermaking, chitin/chitosan has
further applications in this industry beyond water treatment, and this includes surface
coating, dye fixation and paper strengthening. Antibacterial and greaseproof paper
are also in the horizon of future applications of chitosan in the paper industry.
In the wet end application, chitosan and other chitosan derivatives find use as
retention and drainage agents. They act as flocculants and coagulants causing the
aggregation of fine particles and liquids to aid the separation process. The mechanism by which they do this is through electrostatic attraction facilitated by the
attraction between the amino and hydroxyl group and the fine particles thanks to the
polycationic nature of chitosan.
Between cellulose fibers exist voids due to the repulsive force between like
charges. Due to its excellent film-forming property, chitosan covers this void between
the fibers, making for a stronger paper. Chitosan and chitosan derivatives can be
applied as coatings on paper. This is aided by its affinity for cellulose. Chitosan
coatings give antimicrobial properties and improve water vapor and oxygen barrier
properties of the paper. Such papers find use in food packaging and medical uses.
Further application of chitosan in paper production includes its use in dye fixation
for improving the dyeing of paper and chitosan nanoparticle derivatives used in
producing transparent paper (Song et al. 2018).
3.7.11 Electronics
Ubiquity of chitin is further demonstrated by its applicability in electronics. Flexible
electronics, photovoltaic cells and biomedical sensors are some of the applications
which employ chitin. Most of these are using chitin in the deacetylated form (chitosan). The electronics industry is one that makes use of a large amount of polymers, from cable coatings to casings to flexible substrates for photovoltaic cells.
While many of the applications of chitin involve the deacetylated form, chitosan,
some recent applications have explored chitin nanoparticles, for example, in use as
biodegradable, eco-friendly flexible substrates for light-emitting diodes (Jin et al.
2016).
Flexible electronics have become desirable for lightweight, low-cost electronics
such as screens and photovoltaic cells. Being able to process these electronics on
flexible substrates allows for mass reproducible roll to roll processing techniques
at low temperatures such as solvent casting and more portable designs. Recently,
plastics such as polyethylene terephthalate and polyethylene have been used for
such. Even better would be biodegradable polymers for such applications. Chitin
and chitosan and their derivatives have demonstrated suitability for such applications
(Triyana et al. 2018).