Electrospun polydiphenylamine-polyethylene-oxide as a methanol sensor material

Abstract

Polydiphenylamine (or PDPA) possesses excellent properties: e.g, robustness, relatively inexpensive for a monomer, thermal stability, environmental stability, and stability in a larger pH range. Due to these properties, PDPA is a candidate for unique sensory material. The sensitivity of chemical gas sensors is strongly affected by the specific surface area of the sensing materials. A higher specific surface area of a sensing material leads to a higher sensor sensitivity. This work aims to investigate the electrical sensitivity of PDPA pellets and PDPA fibers when they are exposed to methanol vapor. The Dedoped-PDPA (De-PDPA) pellets were doped with HC1 acid at various doping ratios: 1: 1, 10: 1, 100: 1, and 200: 1. PDPA in its blends with PEO at various ratios was also fabricated into fibers by electrospinning. The De-PDPA pellets that had been doped at the ratio of 100 showed the highest electrical sensitivity toward methanol vapor. The electrical sensitivity of the PDPA fibers is relatively low with increasing the amount of PEO when exposed to methanol vapor.