Preparation and characterization of cellulose/polypyrrole conducting composite fibers via in-situ polymerization

Electrically conductive cellulose/polypyrrole (PPy) composite fibers were prepared via in-situ chemical oxidative polymerization of pyrrole by using ferric chloride as an oxidant and p-toluenesulfonic acid (PTSA) as a dopant. The composite fibers were characterized by XPS and SEM-EDXA. Pyrrole concentration had a significant effect on the surface resistivity of composite fibers, especially when pyrrole concentration was less than 1.8 g.L-1. The conductivity of the PPy-coated cellulosic fibers could be controlled by adjusting pyrrole concentration. The threshold concentration of pyrrole was 1.2 g.L-1 when the molar ratio of dopant to pyrrole was 2:1. Very little polymerization reaction in solution occurred when pyrrole concentration was less than 2.5 g.L-1. The XPS results showed that the amount of the PPy coated increased while the doping level first decreased then increased with the increase of pyrrole concentration. The SEM-EDXA results showed that, there was no difference in the amount of PPy coated between the outer surface and the internal wall, and the values of S/N ratio based on the outer surface were higher than those based on the internal wall.