Synthesis and characterization of poly(Vinyl Acetate)/polystyrene/polypyrrole ternary composites

In this study, polypyrrole (PPy) and poly(vinyl acetate)/polystyrene/polypyrrole (PVAc/PS/PPy) ternary composites were synthesized by chemical polymerization and their structures were characterized by various methods and techniques. In the experiments, iron (III) chloride (FeCl3) was used as an oxidizing agent and the ratio of oxidant/monomer was 2/1. Firstly, PPy was synthesized and obtained with 93% yield. Then, PVAc/PS/PPy ternary composites containing various amounts of PPy were synthesized. Moreover, temperature-sensitive folding films of PVAc/PS/PPy ternary composites were prepared. Morphological properties, surface roughness and mechanical properties of films were examined by scanning electron microscopy (SEM), atomic force microscopy (AFM) and stress-strain experiments, respectively. The conductivities of polymer and ternary composites at the room temperature and different temperatures were measured by four probe technique. The conductivity of PPy was determined with a value of 2.45x10-3 Scm-1 at the room temperature. Among the PVAc/PS/PPy ternary composites, 90% PPy containinig composite had the highest conductivity with a value of 2.37x10-3 Scm-1. It was observed that the conductivities of ternary composites increased with increasing temperature. Formations of PPy and ternary composites were supported by fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance spectroscopy (1H-NMR) analyses. Electronic transitions of polymers were determined by UV-vis spectroscopy. The values obtained from the gouy measurements showed that the conducting mechanisms of all the polymers showed a polaron nature. The thermal properties of the polymer and ternary composites were investigated by using thermogravimetric analysis (TGA) and found that they have quite good thermal stability. The glass transition temperatures of polymers and ternary composites were determined by differential scanning calorimetry (DSC). C, N, H contents of PPy and PVAc/PS/PPy ternary composites were determined by elemental analysis. Amount of Fe (mg/g) in polymer structures were determined by inductively coupled plasma optical emission spectroscopy (ICP-OES). X-ray diffraction (XRD) spectra showed the amorphous nature of the polymers.