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EVA nanocomposites summary
Mechanical Properties

Since the eighties, polymeric nanocomposites have been intensely investigated due to the
performance improvement achieved when a small amount of nanosized particles are added to a
polymer matrix
...
Among to their particular properties including flame resistance ,
mechanical properties , gas barrier properties , thermal stability and biodegradability , when
compared to pristine polymers
...
These
improvements include enhanced physical and mechanical properties of high tensile moduli and
strength, increased dimensional stability,decreased gas permeability and flamm- ability, improved
solvent and UV resistance, improved electrical property and increased biodegradability of
biodegradable polymers
...
Clay particles have been added to different polymers including
multilayered PET, epoxy composites and polystyrene/polyethylene
...
Generally, EVA has been accepted for
biomedical applications due to its random structures, which offer high ozone resistance, weather
resistance, and exceptional mechanical properties
...
In contrast, the melt compounded EVA copolymer by
twin screw extruder achieved the highest ambient and in vitro mechanical properties at high
nanofiller content (5wt% organo-MMT)
...
In contrast, the melt compounded EVA copolymer by twin
screw extruder achieved the highest ambient and in vitro mechanical properties at high nanofiller
content (5wt% organo-MMT)
...
When higher loading of nanoclay (5%) was used, the degree of
exfoliation and dispersion decreased which led to severe reduction on the mechanical properties and
biostability of the EVA
...
The resulting composite might exhibit improved thermal, mechanical, rheolo- gical,
electrical, catalytic, fire retardancy and optical properties
...
However, the nanoparticles have a strong tendency
to undergo agglomeration followed by insufficient dispersal in the polymer matrix, degrading the
optical and mechanical properties of the nanocomposites
...
Carbon nanotubes are effective at quite low amounts, for example, for single wall nanotubes
in poly(methyl methacrylate) (PMMA), good fire retardant efficacy is seen at 0
...

[8], [9]

Twin Screw Extruder
Melt compounded EVA copolymer by internal mixer (Brabender plasticoder) achieved the highest
ambient and in vitro mechanical properties at low nanofiller content (1wt% organo-MMT)
...
This was due to
the capability of the twin screw extruder to provide greater shear force for the exfoliation and
dispersion of the high content organo-MMT as compared to internal mixer (Brabender plasticoder)
...

[6], [10]

Barrier properties
Nanocomposites have attracted a great deal of attention recently due to the improvements in the
mechanical, thermal and gas barrier properties of the polymers owing to the size and large surface
area of filler nanoparticles
...
The incorporation of the nano sized clay (nanoclay) into polymer matrices can result in
their remarkable improvement in mechanical, thermal and barrier properties as long as the
nanofillers are well exfoliated and dispersed throughout the matrix
...
Nanoclay is among the most commonly used nanofillers for various
polymeric materials due to its availability, durability and tailorable surface properties [2]
...
The main advantage of nanoclay as reinforcing material in polymer is its ability to enhance
strength, toughness, durability and barrier properties of the host polymer while maintaining its
lightweight, flexibility, and clarity
...
These properties are highly needed
for materials insisted for use in biomedical applications
...
EVA is biocompatible, offers excellent optical clarity, barrier

properties, low-temperature toughness and stress-crack resistance
...
Oliveira and A
...
Charact
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, pp
...


[2]

E
...
Giuliano, and M
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Lett
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01, no
...
105–119, 2011
...
M
...
Marand, J
...
Little, and S
...
Cox, “Transport properties in
polyurethane/clay nanocomposites as barrier materials: Effect of processing conditions,” J
...
Sci
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337, no
...
208–214, Jul
...


[4]

A
...
Alakrach, A
...
Osman, N
...
Noriman, B
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Betar, and O
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Dahham, “Thermal
properties of ethyl vinyl acetate ( EVA )/ montmorillonite ( MMT ) nanocomposites for
biomedical applications,” vol
...
7–11, 2016
...
M
...
J
...
J
...
K
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Bhattachary, “Preparation and Rheological
Characteristics of Ethylene-Vinyl Acetate Copolymer/Organoclay Nanocomposites,” J
...
Sci
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46, no
...
261–273, 2007
...
Fazlina, T
...
Alakrach, “The Effects of Melt Compounding Method on the Ambient
and In vitro Mechanical Properties of EVA / MMT Nanocomposites,” vol
...
75–79,
2015
...
F
...
, “Hybrid silicate nanofillers: Impact on morphology and performance of EVA
copolymer upon in vitro physiological fluid exposure,” J
...
Polym
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, vol
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12,
Mar
...


[8]

S
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Kalia, A
...
Njuguna, Y
...
Kumar, “Surface modification of
inorganic nanoparticles for development of organic-inorganic nanocomposites - A review,”
Progress in Polymer Science
...


[9]

X
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Rathore, P
...
D
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Jimenez-Gasco, E
...
A
...
Degrad
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, vol
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3, pp
...
2011
...
C
...
Soheilmoghaddam, R
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Pour, H
...
Mohamad, “Mechanical,
thermal and flammability properties of ethylene-vinyl acetate (EVA)/sepiolite
nanocomposites,” Polym
...
, vol
...
117–122, Aug
...


Note
These excerpts are taken for my research
You can read the full version in journals mention in references above

Yours sincerely
-AH-



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