Synthesis and characterization of polyindole/polyethlene conducting composites

In this study, polyindole (PIN) and polyindole/polyethylene (PIN/PE) conducting composites were synthesized by chemical polymerization and their structures were characterized by various methods and techniques. In the experiments, FeCl3 was used as oxidizing agent and the ratio of salt/monomer was 3/1. Firstly, PIN was synthesized and obtained with 90% yield. Then, PIN/PE composites containing different amount of PIN were synthesized. The synthesized PIN was used as a diode and its electrical property was determined. The conductivities of PIN and PIN/PE composites at various temperatures were measured by using four-probe technique. It was observed that the conductivity of PIN and PIN/PE composites increased with increasing temperature. The conductivity of PIN was determined with a value of 1,25x10?3 S cm-1 at the room temperature. Among the composites, PIN/PE containing 89% (m/m) PIN had the highest conductivity with a value of 6,16x10?6 S cm-1. It was observed that the conductivity decreased with increasing amount of PE in the composites. From Gouy scale magnetic susceptibility measurements, it was revealed that PIN and PIN/PE composites were found to have polaron nature. Formation of the polymer and composites was supported by FTIR and UV analyses. From FTIR analyses, its was suggested that the polymerization reaction occurred via 2,3 propagation mechanism. The thermal properties of PIN and PIN/PE vii composites were investigated by using thermogravimetric (TGA) and differential scanning calorimetry (DSC) analyses and found that they had shown adequate thermal stability. Morphological structures of the PIN, PE and composites were clarified by using scanning electron microscopy (SEM). Key Words : Polyindole, Polyethylene, Conducting composite, Chemical polymerization