الفهرس 
chapter 1Only 14 pages are availabe for public view
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Abstract
Conducting polymers is a class of functional polymers that have alternating single and double carbon–carbon bonds along the polymeric chains. The emergence of conducting polymers (CPs) has constituted a significant milestone in modern analytical science. The usefulness of these conjugated polymers is a result of their ability to be deposited as thin films onto donor substrates. They have attracted the attention of researchers in textile field due to their potential application in composite with natural, artificial or synthetic fibres. They have good conductivity, high stability and a good film forming property. The conductivity of conducting polymers is attributed to the delocalisation of π-bonded electrons over the polymeric backbone, shows electronic properties, such as low ionisation potentials and high electron affinities.
The thesis entitled “Physico-Chemical Studies of Some Polymers” comprises three main Chapters:
The first Chapter contains a literature survey includes the importance and structural chemistry of conducting polymers through syntheses and study physical properties such as dielectrics and electrical conductivity of some conducting polymers and show the effect of doping process with donor atoms on the conductivity of conducting polymers
The second Chapter involves preparation of polyacrylonitrile (PAN) which have been characterized on the basis of IR. The doping with iodine element was carried out in vacuum chamber technique. The scanning electron microscope (SEM) photos have been carried out for pure PAN and doped PAN with iodine. It was found that the doping process have no effect on the chemical composition of PAN. The thermogravimetric analyses (TGA) (under nitrogen atmosphere) of PAN was carried out shows that PAN starts to degrade at 523 K. The dielectic constants and electrical conductivity were studied and the conduction mechanism was known as correlating barrier hopping (CBH) mechanism by using the behavior of the relationship between the frequency exponent (s) with the temperature. The effect of temperature and frequency on the electrical conductivity of both PAN and PAN/I2 were studied. The effect of doping process of PAN with I2 (at different exposure time) on the electrical properties and the conduction mechanism was studied, It was found that there are clear enhancement of the electrical conductivity with doping process.
The third Chapter involves preparation of polyaniline(PANI), insitu. doped PANI and exsitu. doped PANI by oxidation polymerization method with potassium dichromate (K2Cr2O7) as very oxidizing agent. The formed polymers were characterized on the basis of IR, UV absorbance. The X-ray diffraction (XRD) analyses were carried out for the three samples under investigation and show the crystalline formula of prepared samples. The thermogravimetric analyses (TGA) of PANI, PANI/I2 (insitu.) and PANI/I2 (exsitu.) were carried out to study the degradation process of the three samples under investigation. A comparison between thermal stability of the prepared samples and activation energy of degradation were involve by using Arrhenius relationship. The dielectric constants and electrical conductivity were studied under several frequencies and at different temperature (300-600K). It was found that the chemical doping of PAN with iodine by two different methods (insitu., exsitu.) enhance the electrical conductivity of PANI.