FT-Raman studies on ionic interactions in π-complexes of poly(hexamethylenevinylene) with silver salts

Jong Hak Kim, Byoung Ryul Min, Jongok Won, Yong Soo Kang

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Remarkably high and stable separation performance for olefin/paraffin mixtures was previously reported by facilitated olefin transport through π-complex membranes consisting of silver ions dissolved in poly(hexamethylenevinylene) (PHMV). In this study, the π-complex formation of AgBF4, AgClO4 and AgCF3SO3 with PHMV and their ionic interactions were investigated. FT-Raman spectroscopy showed that the C=C stretching bands of PHMV shifted to a lower frequency upon incorporation of silver salt, but the degree of peak shift depended on the counteranions of salt due to different complexation strengths. The symmetric stretching modes of anions indicated the presence of only free ions up to [C=C]:[Ag]=1:1, demonstrating the unusually high solubility of silver salt in PHMV. Above the solubility limit, the ion pairs and higher-order ionic aggregates started to form. The coordination number of silver ion for C=C of PHMV was in the order AgBF4 > AgClO4 > AgCF 3SO3, but became similar at [C=C]:[Ag]=1:1. The different coordination number was interpreted in terms of the different transient crosslinks of silver cations in the complex, which may be related to both the interaction strength of the polymer/silver ion and the bulkiness of the counteranion.

Original languageEnglish
Pages (from-to)199-204
Number of pages6
JournalMacromolecular Research
Volume14
Issue number2
DOIs
Publication statusPublished - 2006 Jan 1

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Chemical Engineering(all)
  • Organic Chemistry
  • Polymers and Plastics
  • Materials Chemistry

Cite this