8th Liquid Matter Conference September 6-10, 2011 Wien, Austria ...

P4.54Fri 911:10-14:00Thermorheological behavior and miscibility ofPEO/PMMA blends: effects of ion solvationNader Taheri Qazvini, 1 Mahdi Ghelichi, 2 Seyed Hassan Jafari, 2 and Hossein AliKhonakdar 31 College of Science, University of Tehran, P.O. Box 14155-6455, 14176, Tehran,Iran2 College of Engineering, University of Tehran, Tehran, Iran3 Iran Polymer and Petrochemical Institute, Tehran, IranPEO/PMMA miscible blends and block copolymers have been recently introduced as interestingcandidate for use as electrolyte in solid-state lithium batteries [1, 2]. However, adding salt ionsinto a miscible blend can alter the pair interaction of constitutive components and as a result themiscibility of the blend. In this study, the influence of Li + ions on the thermorheological behaviorand miscibility of PEO/PMMA is investigated. To this aim, lithium perchlorate (1% wt.) is addedto the miscible PEO /PMMA blend in the specific composition of 80% wt. PMMA. The resultsshowed that the pair interactions of miscible PEO /PMMA are altered via adding lithium perchloratesalt. Preferential solubility of Li + ions by the PEO chains provides the thermodynamic drivingforce that reduces the miscibility of this blend. Moreover, the influence of altered interactions onthe thermorheological behavior of this blend is studied in the linear viscoelastic regime. A directresult of affected miscibility is observed in the form of severe failure of time-temperature superpositionafter creating master curves in the case of doped PEO /PMMA in comparison to the undopedblend. In another word, salt ions intensify the dynamic heterogeneities that are usually reportedfor PEO /PMMA. Our results are in agreement with the reported theoretical predictions [3] whichpropose reduced miscibility upon addition of salt ions into a miscible blend that both componentshave low dielectric constants. [1] K. Jeddi, N. Taheri Qazvini, S. H. Jafari, H. A. Khonakdar, J.Polym. Sci. : Part B: Polym. Phys. , 48, 2065-2071 (2010). [2] A. G. Ruzette, P. P. Soo, D. R.Sadoway, A. M. Mayes, J. Electrochem. Soc. , 148, A537-A543 (2001). [3] Z. G. Wang, J. Phys.Chem. B, 112, 16205-16213 (2008).54