Synthesis and Characterization of PEDOT:P(SS-co-VTMS) with Hydrophobic Properties and Excellent Thermal Stability

Wonseok Cho; Soeun Im; Seyul Kim; Soyeon Kim; Jung Hyun Kim

doi:10.3390/polym8050189

Synthesis and Characterization of PEDOT:P(SS-co-VTMS) with Hydrophobic Properties and Excellent Thermal Stability

Polymers (Basel). 2016 May 12;8(5):189. doi: 10.3390/polym8050189.

Authors

Wonseok Cho¹, Soeun Im², Seyul Kim³, Soyeon Kim⁴, Jung Hyun Kim⁵

Affiliations

¹ Department of Chemical and Biomolecular Engineering, Yonsei University, 134 Shinchon-Dong, Seodaemoon-Gu, Seoul 120-749, Korea. intersv@yonsei.ac.kr.
² Department of Chemical and Biomolecular Engineering, Yonsei University, 134 Shinchon-Dong, Seodaemoon-Gu, Seoul 120-749, Korea. imse218@yonsei.ac.kr.
³ Department of Chemical and Biomolecular Engineering, Yonsei University, 134 Shinchon-Dong, Seodaemoon-Gu, Seoul 120-749, Korea. kimseyul84@yonsei.ac.kr.
⁴ Department of Chemical and Biomolecular Engineering, Yonsei University, 134 Shinchon-Dong, Seodaemoon-Gu, Seoul 120-749, Korea. kimso88@yonsei.ac.kr.
⁵ Department of Chemical and Biomolecular Engineering, Yonsei University, 134 Shinchon-Dong, Seodaemoon-Gu, Seoul 120-749, Korea. jayhkim@yonsei.ac.kr.

Abstract

Hydrophobic and comparatively thermally-stable poly(3,4-ethylenedioxythiophene), i.e., poly(styrene sulfonate-co-vinyltrimethoxysilane) (PEDOT:P(SS-co-VTMS)) copolymer was successfully synthesized via the introduction of silane coupling agent into the PSS main chain to form P(SS-co-VTMS) copolymers. PSS and P(SS-co-VMTS) copolymers were successfully synthesized via radical solution polymerization, and PEDOT:P(SS-co-VTMS) was synthesized via Fe⁺-catalyzed oxidative polymerization. The characterization of PEDOT:P(SS-co-VTMS) was performed through an analysis of Fourier transform infrared spectroscopy (FTIR) results, water contact angle and optical images. The electrical properties of conductive PEDOT:P(SS-co-VTMS) thin films were evaluated by studying the influence of the VTMS content on the electrical and physical properties. The conductivity of PEDOT:P(SS-co-VTMS) decreased with an increase in the VTMS content, but was close to that of the PEDOT:PSS, 235.9 S·cm^-1. The introduction of VTMS into the PSS copolymer improved the mechanical properties and thermal stability and increased the hydrophobicity. The thermal stability test at a temperature over 240 °C indicated that the sheet resistance of PEDOT:PSS increased by 3,012%. The sheet resistance of PEDOT:P(SS-co-VTMS), on the other hand, only increased by 480%. The stability of PEDOT:P(SS-co-VTMS) was six-times higher than that of the reference PEDOT:PSS.

Keywords: PEDOT:PSS; PSS copolymer; conducting polymer.