Conformational, thermal, and ionic conductivity behavior of PEO in PEO/PMMA miscible blend: Investigating the effect of lithium salt. Issue 4 (24th December 2012)

• Record Type: Journal Article
• Authors: Ghelichi, Mahdi; Qazvini, Nader Taheri; Jafari, Seyed Hassan; Khonakdar, Hossein Ali; Farajollahi, Yaser; Scheffler, Christina
• Is Part Of: Journal of applied polymer science. Volume 129:Issue 4(2013:Aug. 15)
• Page Start: 1868
• Page End: 1874
• Publication Date: 2012-12-24
• Subjects: Polymers -- Periodicals; Polymerization -- Periodicals; 668.9
• DOI: 10.1002/app.38897
• Languages: English
• ISSNs: 0021-8995

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>In this research, influence of incorporating LiClO₄ salt on the crystallization, conformation, and ionic conductivity of poly(ethylene oxide) (PEO) in its miscible blend with poly(methyl methacrylate) (PMMA) is studied. Differential scanning calorimetry showed that the incorporation of salt ions into the blend suppresses the crystallinity of PEO. The X‐ray diffraction revealed that the unit‐cell parameters of the crystals are independent of the LiClO₄ concentration despite of the existence of ionic interactions between PEO and Li cations. In addition, the complexation of the Li⁺ ions by oxygen atoms of PEO is investigated via Fourier transform infrared spectroscopy. The conformational changes of PEO segments in the presence of salt ions are studied via Raman spectroscopy. It is found that PEO chains in the blend possess a crown‐ether like conformation because of their particular complexation with the Li⁺ ions. This coordination of PEO with lithium cations amorphize the PEO and is accounted for suppressed crystallinity of PEO in the presence of salt ions. Finally, electrochemical impedance spectroscopy is used to characterize the ionic conductivity of PEO in the PEO/PMMA/LiClO₄ ternary mixture at various temperatures. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013</p> </abstract>