Polypyrrole/Natural Zeolite Composite Prepared byIn SituOxidative Polymerization: Thermal and Humidity Sensing Properties

Abstract

Composite of polypyrrole (PPy) and natural zeolite (NZ) was prepared by chemical polymerization of pyrrole in the presence of zeolite dispersed in aqueous medium. Results of elemental analysis showed that the percentage amount of dopant in the structure of composites was reached a value of as high as 35.5%. PPy content and conductivity of composites obtained under the tried polymerization conditions changed between 8% and 55% and 3.0 × 10 −3 and 17 × 10 −2 S/cm, respectively. The conductivity of composites prepared by chemical polymerization was higher than those prepared by physically mixing of the components of composite. Change in the resistivity of PPy/NZ composite monitored by heating-cooling cycles in the temperature range of 0-60 • C repeated five times, we noticed that the composite showed more repeatable results compared to that of its conductive component PPy. Size distribution analysis showed that particle size of NZ in the composite increased as a result of PPy coating and particle size of composite containing 43% PPy reached up to 30 μm of d(0.9). FTIR, TGA, XRD and SEM techniques were also used for the characterization of PPy/NZ composite.

Influence of pyrrole feeding ratios on physicochemical characteristics of high-performance multilayered PPy/PVC/PDA@FG-NH2nanocomposites

“…24 The characteristic peaks at 1560 and 1406 cm −1 correspond to stretching vibrations of C=C and C–N of PPy. 25 The higher intensity of peaks also reflects longer effective π -conjugation along the PPy chains which in turn increase the conductivity of resulting nanocomposites 26 and are in good agreement with reported literature for PPy. 27 Also, peak at 1054 cm −1 corresponds to in-plane deformation of the C–H and N–H bonds of pyrrole ring.…”

“…In the same way, the lamellar structure of graphite sheets also limited the activity of PPy molecules and hence hindering the thermal decomposition reaction. 24,25,46…”