Tez özetleri Astronomi ve Uzay Bilimleri Anabilim Dalı

Fractıonatıon Of Poly(Phenylene Oxide) And Investıgatıon Of Molecular Weıght Dıstrıbutıon

In this study, the distribution of the molecular weight has been determinated by fractionation of Poly(2,6-dimethyl-1,4-phenylene oxid) and Mark-Houwink constants were found (K ve ) for the solvent chloroform at 25⁰ C.

The structural analysis of every fractions of PPO has been studied by using Attenuated Total Reflactance (ATR) . The Attenuated Total Reflactance spectrums have been obtained for every fractions of PPO. In order to study the structural analysis the thermal analysis of the fractions of PPO has been studied by using Differantial Scanning Calorimeter (DSC), Gel Permeation Chromatography (GPC) has been used to find the molecular weight of the fractions. The data obtained from the viscosities of each fractions the Mark-Houwink constants have been calculated.

The results of molecular weight of the fractions show that, first fraction has the highest molecular weight and the highest glass transition temperature (T_g ) and also the longest flowing time. In every fractionation step the molecular weight of the fraction and T_g decrease.

From the viscosity measurements of fractions of PPO and the results of GPC Mark - Houwink constants (K and ) of PPO in chloroform were calculated at 25⁰C.