الفهرس 
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Abstract
Silk is crystalline, homogenous in structure, hygroscopic in nature, light
in weight and is the longest and the strongest of all natural fibers. Soft, has
exceptional handle, lustrous, has comfortable wear properties and hygienic,
silk also has an excellent affinity to dyes
Polyester is hydrophobic, because of the lack of polarity and the
crystalline structure of the polymer that resist the entry of water molecule into
the polymer system and very good tenacity. It can be surface modified using a
variety of techniques including plasma, corona discharge, ion beam, laser
treatment and photo-initiated graft polymerization; Polyethylene terephthalate
is suitable substrate for several reasons. It contains carbonyl groups that are
capable of hydrogen bonding.
The pre-treatment and finishing of textile by non-thermal Dc-cold
plasma technologies becomes more popular as a surface modification
technique, where this treatment does not require the use of water and
chemicals, resulting in a more economical and ecological process .
The objective of plasma diagnostics is to obtain information about the state of
the plasma by means of different experimental techniques. Knowledge of
plasma characteristics is required to understand fully the effects of the
different physical processes taking place in the plasma and to deduce from
them its properties. The application of plasma treatments for improving
wettability of all possible fiber types was obtained with varied success
degrees. It offers numerous advantages over the conventional chemical
processes.
A non-thermal (or Dc-cold or low temperature) plasma is a partially
ionized gas with electron temperatures much higher than ion temperatures.
The high-energy electrons and low-energy molecular species can initiate
reactions in the plasma volume without excessive heat causing substrate
degradation. Non-thermal plasmas are particularly these applied treatments on
the performance of silk and polyester fabrics in terms of air permeability,
water absorbency, mechanical properties, electron spin resonance
spectroscopy (ESR), fiber surface morphological changes, and antibacterial
activity.
this thesis divided into three main sectors; characterization testes to get
the optimum conditions for plasma treatment, applied testes to know the
effect of plasma treatment on silk dyeing and its antibacterial properties and
synthesis and characterization of nanosilver particles.
Characterization Tests
Silk Fabric
The Effect of Plasma Exposure Time on Air Permeability of Silk
Fabric.
It is clear that, there was a gradually increase in the air permeability
values of different oxygen plasma and oxygen/ argon mixed gas plasma
exposed samples by increasing the time range with an increasing by a percent
of (1.6%) for oxygen plasma, while for oxygen/ argon mixed gas plasma it is
(18%) relative to their blank mates at the optimum conditions of treatment
that is (30 sec.)
The Effect of Plasma Current on Air Permeability of Silk fabric.
It is clear that, there was a gradually increase in the air permeability
values of both oxygen/ argon mixed gas plasma and oxygen plasma treated
samples in the current range from (30 mA.), up to (55 mA.), with an
increasing by a percent of (1.6%) for oxygen plasma, while for oxygen/ argon
mixed gas plasma it is (18%) relative to their blank mates at the optimum
conditions of treatment. The air permeability values increased by increasing
the current of exposure up to (55mA.), this increase may be due to the effect
of argon gas with slightly high molecular mass that increase the porosity of
treated silk samples.
The Effect of Plasma Pressure on Air Permeability of Silk
Fabric.
Air permeability values of the examined Silk samples increased
gradually by decreasing the applied pressure in plasma chamber reaching
maximum increase using (0.2 torr) in case of both oxygen/ argon mixed gas
plasma and oxygen plasma compared to the values of blank unexposed
samples
This result can be explained in view of the effect of pressure on energy of the
charged particles leading to a large effect on the fabric surface, thus increasing
their permeability in air.
The Effect of Plasma Exposure Time on Tensile Strength of Silk
Fabric.
The tensile strength value clarify their decreasing up to exposure time
(120) sec., it may be due to the oxidation effect of oxygen plasma on silk
fibers which can cause the reduction of the tensile strength. However, the
maximum loss in tenacity was (2.21%) and (2.64%) for samples treated with
oxygen and oxygen/ argon plasma at the optimum conditions respectively.
This maximum reduction in strength is still in the acceptable range. Maximum
loss of (20%) in tenacity is usually acceptable in chemical treatment of
textiles.The results of tensile properties measurements confirm that both types
of plasma treatments can be used on silk yarn without significant adverse
effect on the physical properties of the fibers, especially when applied at
durations up to (30) sec.
The Effect of Plasma Current on Tensile Strength of Silk
Fabric.
The data manifested by the tensile strength value clarify their decrease
up to current of (55) mA in both plasma oxygen and oxygen/ argon mixed gas
treatment, it is due to the oxidation effect of oxygen plasma on silk fibers,
which may cause the reduction of the tensile strength, strength values. The
other reason is the effect of plasma on increasing the amorphosity of treated
fabrics and hence weakening their strength.
The Effect of Plasma Pressure on Tensile Strength of Silk
Fabric.
The data manifested by the tensile strength value clarify their
decreasing up to exposure pressure (0.2) torr. It may be due to the oxidation
effect of oxygen plasma on silk fibers which can cause the reduction of the
tensile strength, then by increasing the plasma hydrostatic pressure the
fabric damage by the thermal effect of plasma (184). However, the maximum
loss in tensile strength was (2.21%) and (2.64%) for samples treated with
oxygen and oxygen/ argon plasma at the optimum conditions respectively.
The Effect of Plasma Exposure Time on Electron Spin
Resonance Spectroscopy (ESR) of Silk Fabric.
Plasma treatment of Silk samples resulted in more surface activation of
them up to 30 sec. for Oxygen and Oxygen/ Argon mixed gas plasma
treatments.
The peak intensity values are higher in case of mixed gas plasma treatment
than in single gas plasma treatment. In addition, a second activation peak can
be observed on following up of the different appeared peaks by increasing the
exposure time
The Effect of Plasma Current on Electron Spin Resonance
Spectroscopy (ESR) of Silk Fabric.
It is clear that there is an increase in peak intensity values for plasma
treated silk indicating more surface activity of them up to (45) mA., for both
oxygen and oxygen/ argon mixed gas plasma treatments.
The peak intensity is higher in case of mixed gas plasma treatment than single
gas plasma treatment.
The Effect of Plasma Pressure on Electron Spin Resonance
Spectroscopy (ESR) of Silk fabric.
It is clear that there is an increase in peak intensity values for plasma
treated silk indicating more surface activity of them up to (0.3) torr., for
oxygen and oxygen/ argon mixed gas plasma treatments.
The peak intensity is higher in case of mixed gas plasma treatment than single
gas plasma treatmen.