화학공학소재연구정보센터
Solid State Ionics, Vol.214, 6-12, 2012
Synthesis and properties of chemically cross-linked poly(vinyl alcohol)-poly (acrylamide-co-diallyldimethylammonium chloride) (PVA-PAADDA) for anion-exchange membranes
Alkaline anion-exchange membranes were prepared from poly(vinyl alcohol) and poly(acrylamide-co-diallyldimethylammonium chloride) by blending, then chemical cross-linking using glutaraldehyde as the cross-linking agent (PVA-PAADDA-GA). Membranes were characterized by Fourier-transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). OH- conductivities in the range of 7.7 x 10(-4)-3.03 x 10(-3) S cm(-1) were obtained for PVA-PAADDA-GA membranes at room temperature (23 +/- 2 degrees C) along with the IEC values changed from 0.91 to 1.63 mequiv g(-1). The temperature dependences of OH- conductivities followed the Arrhenius relationship at a temperature range from 20 to 90 degrees C. The apparent activation energy for OH- conduction was in the range of 15-19 kJ mol(-1) depending on PAADDA content in the polymer. High alkaline stability of PVA-PAADDA-GA membranes was retained after conditioning in 6.0 M KOH at 80 degrees C for 24 h. Also, the membranes showed excellent dimensional stability in both hot water and hot methanol solutions at 90 degrees C. Although a relatively high water uptake (more than 2-fold of Nafion 115), the PVA-PAADDA-GA membranes showed excellent methanol resistance with the methanol permeability ranged from 2.85 to 4.16 x 10(-7) cm(2) s(-1), which were 5-6 times lower than that of the Nafion 115. (C) 2012 Elsevier B.V. All rights reserved.