الفهرس 
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Abstract
The studies of spectral and physical properties ofNitril
polypropylene blends in the present work can be summarized as How:
1-The effect of nitrile butadiene rubber(NBR): Polypropy ene(PP)
ratio has been studied by using the gel method and mechanical pr perties,
scanning electron microscope to obtain the best ratio of such ble d which
reflects the compactability of of the rubber-plastic blends. T~e study
showed that the best ratio is 60:40 (NBRlPP).
Different polyfunction monomer (compatibilizer) have been used to test
the suitable one to enhance the electron irradiation cross linking in such
blend. It is found that 1,6 hexan dial diocrylate (HDDA) gives higher
contribution to crosslinking under electron irradiation.
The (DSC), (FTIR), (TGA) and tensile strength studies were used to
study the expected compactability of such blends under electron
irradiati on.
2-The effect of HAP carbon black on the electrical conduction and
dielectric properties of electron irradiation NBRIPP (60/40) blend was
studied in the temperature range (30-IOOCo ) and frequencies range ( 500-
4x I06
) The conductivity dependence exhibits power law relationship with
power S ( 0.5 < S< I ).The values of S<l suggest hopping conduction
process between filled and unfilled states while the values higher than
one imply the contribution of different conduction process.
The electrical conductivity, in general, increases by increasing carbon
black concentration for the different irradiation doses. This has been
discussed according to decrease of the carbon particle and/or aggregates
separation distances which reduce the electron hopping paths. The
electrical conductivity of NBRJPP carbon black loaded blends changed
irregularly with the variation of electron irradiation dose except 50 and
150 KGy. The values of conductivity decreases by increasing
Abstract
temperature. This is discussed on the bases of the increase of conduction
path (hopping distance) as a result of the thermal expansion of the blend
which leads to an increase of carbon particles or aggregates separation
distance.
The study of the effect of electron irradiation dose, carbon black
concentration and temperature on the dielectric parameters, pennitivity
and dielectric loss illustrates that a higher values of E and E” for
irradiation samples are obtained. In addition maximum values of Eor Elf
are obtained at 50 kGy. In general E and E” decreases by increasing
frequency which reflects the little response of E or E” by increasing
frequency. The maximum in E or E” at 50 KGy is attributed to the
maximum polarization as a result of the optimum bond enhancement as
such dose. The higher values of Eor Elf are discussed according to the
interfacial polarization.
3-The effect of carbon black concentration and electron irradiation
dose on the mechanical properties is studied, the study show an increase
radiation dose. where as it decrease, in general, by increasing carbon
concentration. The strain at break showed a maximum around 50 Phr of
carbon black. It also showed maximum strain at 50 kGy radiation dose.