Preparation and characteristics of crosslinked sulfonated poly(phthalazinone ether sulfone ketone) with poly(vinyl alcohol) for proton exchange membrane

详细信息	查看全文 | 推荐本文 |

• 作者：Shuang Gu ; Gaohong He ; Xuemei Wu ; Yingjie Guo ; Hongjing Liu ; Lin Peng ; Gongkui Xiao
• 关键词：Sulfonated poly(phthalazinone ether sulfone ketone) ; Proton exchange membrane ; Crosslinking ; Polyelectrolytes ; Poly(vinyl alcohol)
• 刊名：Journal of Membrane Science
• 出版年：2008
• 期刊代码：55_03767388
• 类别：ch
• 出版时间：1 April 2008
• 卷：312
• 期：1-2
• 页码：48-58
• 文件大小：917 K

摘要

In order to further overcome the trade-off between high conductivity and good mechanical property of proton exchange membrane (PEM), direct covalent crosslinking of sulfonated poly(phthalazinone ether sulfone ketone) (SPPESK) and poly(vinyl alcohol) (PVA) was prepared through post-heating process. Polymer PVA has attractive advantages to be a crosslinker with SPPESK, since the crosslinking of SPPESK with PVA requires relatively lower crosslinking temperature and has much higher stability in water, compared with small molecule crosslinker of glycol and glycerol. The crosslinking is confirmed by solubility change and analysis of ion exchange capacity (IEC) and sulfur content (C_S) of uncrosslinked and crosslinked SPPESK with PVA (Un S-P and Cr S-P). Calculation of degree of crosslinking (DC) of sulfonic group shows that most –SO₃Hs of SPPESK are not involved in the crosslinking, which can maintain the ion exchange and proton transport function. ATR-FTIR spectra analysis manifests the PVA in Cr S-P are oxidized and dehydrated during the crosslinking process with SPPESK. Cr S-P membrane still has higher thermal stability, despite T_d (252–273 °C) is less than that (306 °C) of pristine SPPESK. SEM images and XRD patterns show that the Cr S-P is a homogenous and amorphous material. Water uptake of Cr S-P membrane decreases with increasing PVA content, and Cr S-P membrane with lower PVA content (e.g. 15%and 20%) has high water uptake (111.1%and 98.0%) at 80 °C. All the swelling ratio values of Cr S-P (15–35%of PVA content) are at a lower level (≤36%) even at 80 °C. Some Cr S-P membranes (with lower PVA content) have much higher conductivity than that of stable pristine SPPESK, e.g. conductivity of S-P 85/15 reaches 2.00 × 10⁻² S cm⁻¹ which is almost twice as that (1.03 × 10⁻² S cm⁻¹) of SPPESK DS 81%membrane. All above properties of Cr S-P membrane (especially PVA content: 15–20%) indicate the kind of crosslinked sulfonated polymer with PVA is another alternative or prospective approach to prepare PEM.