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Chuah Shu Chin
Fariza Fuziana bt Yacob
Lim Weng Keat
Low Mei Ching
Mohamad Azrul Drahman
Mohd Zaidan bin Abdul Aziz
Sawita binti Amir
B050810194
B050810220
B050810181
B050810215
B050810178
B050810281
B050810051
•Nanostructured composite fiber are in one area where we
see the early blooming of nanotechnology.
•Most of the nanocomposite fibers use fillers:
 Nanoparticle
 Graphite nanofiber
 CNTs
•Nano-sized that used to improved the performance of in
textiles are:
Carbon nanofibers and carbon black nanoparticle
Clay nanoparticle
 Metal oxide nanoparticle
 Carbon nanotubes.
Nanofiller
Carbon
nanofibers
and carbon
black
nanoparticle
Clay
nanoparticle
Properties
High chemical resistance
Electrical conductivity
Effect on the textiles
Carbon black- improved abrasion
resistance and toughness
Nanofiber- increased tensile
strength
Electrical, heat and
chemical resistance
Block UV light
Flame retardant,
anticorrosive
Improved tensile strength, tensile
modulus, flexural strength and
flexural modulus
Metal oxide Photocatalytic ability
nanoparticle Electrical conductivity
(MgO, ZnO) UV absorption
Carbon
nanotubes
Incorporating ZnO into nylon
produce composite fiber that
shield UV light and have antistatic properties
Good thermal conductivity Increased toughness and stiffness
Electrical conductivity
100x tensile strength of
steel
Electrospinning
Deposition
layer of coating
onto the
surface of fiber
• Charge polymer melt is extruded through a
small nozzle (needle or pipette tip)
• The charged is drawn toward grounded
collecting plate (meta screen, plate or mandrel)
• As the jet travel, solvent evaporates leaving a
non-woven nanofiber
• The thickness of each layer is in nanometer
range
• A number of methods have been used to apply a
nanocoating to the fiber surface
Developments of nanotechnology in textiles
1) Upgrading existing functions in performances of textile
materials
2) Developing smart & intelligent textiles with unprecedented
functions
Stainresistant
Odour
control
UVprotection
Ultrahydrophobic/
Water resistant
TEXTILE
PERFORMANCES
Antimicrobial
activity
Antistatic
Wrinkle
resistant
Shrink
proof
Antimicrobial
activity
Antimicrobial body wear:
 customer awareness of hygiene
 odour control
 medical applications
(e.g. Neorodermatitis)
 silver nanoparticles in the fiber
 silver nano-coating
 high washing fastness
Nano-sized Ag, TiO2 & ZnO are used to impart
anti-bacterial properties.
Nano-Ag particles have an extremely large
specific surface area, thus increasing their contact
with bacteria or fungi & vastly improving their
bactericidal
and
fungicidal
effectiveness
(Zgondek, 2008).
The textile structure &
application of nanotechnology
on antimicrobial activity
(Beringer, 2005)
UV-protection
How to improve UV
protection factor (UPF)
of textiles
Fabric design
-Tighter weaving or knitting
-Higher weight
Textile finishing
-Organic dyes absorbing UV light
- Optical brighteners (in
detergents)
- Dark coloration
Photo catalysis mechanism of
TiO2
(Source: Samal et al., 2010)
Fibermodification
-TiO2, ZnO nano pigments for
dulling of chemical fibers
-Coating – to prevent photocatalytic
reactions
Fiber Raw Materials:
1) Polyester (PET, PPT, PBT)
2) Polyamide (PA 6, PA 6,6)
3) Natural fibers (CO, WO, LI)
(Source: Beringer, 2005)
Anti-static
Material: nano-ZnO
not only it repel static, but also
repels statically attractive
substances (e.g. dog hair, lint &
dust) (Hauser, 2006).
Textiles that resist static
(Source: Hauser, 2006)
Method: direct precipitation with zinc chloride & sodium carbonate
anhydrous as raw materials.
Cotton fabric & polyester fabric: finished by pad-dry-cure process
with antistatic finishing agent (compounded with nano-ZnO).
The charge density of the density of the polyester fabric is about 10
times as that of the cotton fabric (Fan and Junling, 2009).
Ultrahydrophobic/
Water resistant
Method to fabricate
ultrahydrophobic textile
materials:
cobinations of polystyrene
grafted layers (low surface
energy component) &
silver/silica/calcium carbonate
nanoparticles (roughness
initiation component)
Static water contact angle on (a)
PET fabric grafted with PS only (no
silver) (b) ultrahyrophobic fabric
Stainresistant
Method: Admicellar polymerization
-involves emulsion polymerization
-durable finishes: high performance
in stain resistance & repellency
(Hanumansetty, 2012)
Figure 9: Stain resistance
for untreated and treated
fabric with PA2 with different
staining agents
(Hanumansetty, 2012).
The mechanism of self-cleaning textile (Source: Samal et al., 2010).
The self-cleaning surface by lotues effect.
Odour
control
Cyclodextrins can be
incorporated into a
fabric finish to remove
odour.
Cyclodextrins have a
unique
molecular
structure, composed of
a hydrophobic cavity,
with a hydrophilic
exterior.
The mechanism
of odour control
by applying an
antimicrobial
finish
(Source:
Hauser, 2006)
Wrinkle
resistant
Resin treated cotton.
Resins are used to make the cotton wrinkle free.
The resin treatment also blocks cotton’s natural ability to absorb
moisture (Hauser, 2006).
Shrink
proof
Deficiency of wool - shrinkage (felting) & pilling.
Chemical
treatment
Plasma
treatment
Treatments &
methods of
application
Cyclodextrin
sericin treatment
Enzymatic
treatment
The
hydrophobic
nature
&
scale
structure of the wool
fiber lead to the fiber
to move towards their
root
end
under
mechanical action in
the wet state.
Chemical
treatments:
1.Coating with resins
(e.g. Polyamide
epichlorohydrin)
onto wool fibers.
2.Morphological
modification of the
cuticular
(protective/outer
cellular layer) cells.
Nano-particles such as metal oxides and ceramics are
also used in the textile finishing to alter surface properties
and impart textile functions.
Nano size particles have a larger surface area and hence
higher efficiency than larger size particles. Besides, nano
size particles are transparent and do not blur color and
brightness of the textile substrates.
Continued…
The fabric treated with nano-particles TiO2 and MgO replaces
fabrics with active carbon, previously used as chemical and
biological protective materials.
The photo-catalytic activity of TiO2 and MgO nano-particles
can break harmful and toxic chemicals and biological agents.
These nano-particles can be engineered to adhere to textile
substrates by using spray coating or electrostatic methods.
ZnO nano-particles:
By using a simple water-based technique, ZnO nano particles was dispersed inside a soluble
starch matrix.
Water are used as a solvent in synthesis of nano-particles that causes an immediate
agglomeration due to high polarity of water. To overcome agglomeration, soluble starch was
added before the reaction starts.
Zinc oxide (ZnO) nanoparticles embedded in polymer matrices like soluble starch are a good
example of functional nanostructures with potential for applications such as UV-protection
ability in textiles and sunscreens, and antibacterial finishes in medical textiles and inner
wears.
Nanoparticles are applied to textiles and fixed to the substrate by the use of functional
polymers.
(e.g. modified polyamines, polyethylene imine, star-shaped prepolymers with isocyanate
groups, epoxides, acrylic acid esters, fluoropolymers etc.)
SUMMARY:
Simple Water-based
Technique
modified polyamines,
polyethylene imine, epoxides,
acrylic acid esters,
fluoropolymers
SELF ASSEMBLED
NANOLAYERS
(SAN)
INTRODUCTION
• Challenge to traditional textile coating.
• Still in embryo stage.
• Target chemical molecules form a layer of
thickness < nanometer on the surface of
textile materials.
• Additional layers  Top of the existing ones
= Nanolayered structure
ELECTROSTATIC SELF-ASSEMBLY
• WHY ELECTROSTATIC SELF ASSEMBLY?
Protective function
Self-healing function
Flexibility
Compatibility
Environmental friendly
ELECTROSTATIC SELF-ASSEMBLY (CONT…)
Dipping a positively charged substrate
into a dilute aqueous solution of an
anionic polyelectrolyte.
Allowing the anionic polymer to adsorp
on the surface.
The negatively charged coated
substrate is rinsed and then dipped
into a solution of cationic
polyelectrolyte.
Multilayer films are created.
Polyelectrolyte Adsorption
• Surface phenomenon where long-chained polymer
molecules with charged groups bind to a surface that is
charged in the opposite polarity.
• The polymers bonds to the surface via intermolecular
forces and the charges created by the dissociation of
various side groups of the polymer.
• Because the polymer molecules are so long, they have a
large amount of surface area with which to contact the
surface and thus do not desorb as small molecules are
likely to do. This means that adsorbed layers of
polyelectrolytes form a very durable coating.
• By kinetic control of adsorption , film thickness and
growth can be controlled.
The film was constructed by the sequential adsorption of
oppositely charged species in a layer-by-layer fashion
from dilute solutions. The surface coverage increases
linearly with the number of deposition steps.
Entropy
of
polymer
chains
Hydrogen
bond
Charge
transfer
interactions
Molar
mass
Factors of
Electrostati
cs Selfassembly
Hydrophobic
interactions
Flexibility
of chains
Ion
exchange
capability
What are the potential applications of highly
water repellent textile materials?
Rainwear - repel the
water during raining day
Upholstery – textile used to
cover the furniture
Sportswear
Protective clothing
Automobile interior fabric
What is the application of nanotechnology for
textile in military?
Lightweight bulletproof vests and shirts
Nanotechnologists have come up with a
super strong, flexible fiber that can
conduct heat and electricity. It could be
made into a modern version of chain mail,
the heavy metal mesh worn by medieval
knights. If woven from the new
fiber, modern chain mail could be light as
a cotton shirt, but bulletproof.
chain mail
modern version of
chain mail
What are the future prospects and new
functions in textiles to be developed?
Future Prospect
• Two focus:
– Upgrading existing functions and performances of
textile materials.
– Developing smart and intelligent textiles with
unprecedented functions.
The new functions with
textiles to be developed:
Wearable solar cell
and energy storage
Multiple and sophisticated
protection and detection
Sensors and information
acquisition and transfer
The new functions with textiles to be
developed:
Health-care and
wound healing
functions
Self-cleaning
and repairing
functions
REFERENCES
Lei, Q. and Hineroza, J.P., 2004. Application of Nanotechnology for High
Performance Textile. Journal of Textile and Apparel, Technology and
Management, 4 (1), pp.1-7.
Ramaratnam, K., Iyer, S.K., Kinnan, M.K., Chumanov, G., Brown, P.J. and
Luzinov, I., 2008. Ultrahydrophobic Textiles Using Nanoparticles: Lotus
Approach. Journal of Engineered Fibers and Fabrics, 3 (4),pp.1-14.
Fan and Junling, 2009. Preparation of Nano-ZnO and Its Application to the
Textile on Antistatic Finishing. Internantional Journal of Chemistry, 1 (1), pp.1822.
Jeevani, T., 2011. Nanotextile – A Broader Perspective. Nanomedicine &
Nanotechnology, 2 (7), pp.1-5.
Hanumansetty, S., Maity, J., Foster, R. and O’Rear, E.A., 2012. Stain
Resistance of Cotton Fabrics before and after Finishing with Admicellar
Polymerization. Applied Science, 2 (10), pp.192-205.
Zgondek, E.M., Bacciarelli, A., Szynkowska, M.I. and Kolodziejczyk, M., 2008.
Antibacterial Properties of Silver-Finished Textiles. FIBRES & TEXTILES in
Eastern Europe, 16 (5), pp.101-107.
REFERENCES
(cont.)
Beringer, J., 2005. Nanotechnology in Textile Finishing – State of the Art and
Future Prospects, Germany: Hohenstein Institute.
Hauser, P., 2006. Advances and Trends in Textile Wet Processing Chemicals.
Journal of Textile and Apparel, Technology and Management, 5 (1), pp.1-4.
Samal, S.S., Jeyaraman, P. and Vishwakarma, V ., 2010. Sonochemical
Coating of Ag-TiO2 Nanoparticles on Textile Fabrics for Stain Repellency and
Self-Cleaning-The Indian Scenario: A Review. Journal of Minerals, Materials
Characterization & Engineering, 9 (6), pp.519-525.
Allam, O.G., 2011. Imrpoving Functional Characteristics of Wool and Some
Synthetic Fibers. Open Journal of Organic Polymer Materials, 3, pp.8-19.