海藻酸钠阳离子交换膜的改性及表征

以海藻酸钠(SA)为原料,以羧基化多壁碳纳米管(cMWCNTs)为改性剂,再通过涂敷浸渍的方法与热塑性聚氨酯(TPU)导电无纺布复合得到改性SA阳离子交换膜。利用热失重分析仪(TG)、扫描电子显微镜(SEM)、X射线衍射仪(XRD)、绝缘电阻测试仪和万能材料试验机对SA阳离子膜的结构和性能进行表征。结果表明:与SA阳离子交换膜相比,经cMWCNTs和TPU导电无纺布改性后膜的电阻率显著降低,导电能力提高;改性SA阳离子膜的表面平整、光滑,未出现气泡等缺陷,TPU导电无纺布与SA膜间界面结合力较强;改性后,膜的热稳定性和力学性能得到显著提高。

Modification and characterization of sodium alginate cation-exchange membrane

The modified sodium alginate(SA)cation-exchange membrane was prepared,using SA as raw material and cMWCNTs as modifier,then being composited with conductive thermoplastic polyurethane(TPU)nonwoven fabric by a coating and dipping method.The structure and properties of the membranes were characterized by thermogravimetric analyzer(TG),scanning electron microscope(SEM),X-ray diffractometer(XRD),insulation resistance tester and universal material testing machine.The results shown that:compared with SA cation-exchange membrane,the electrical resistivity of SA membrane was significantly decreased after being modified by cMWCNTs and conductive TPU nonwoven fabric,resulting in improved electrical conductivity of the SA membrane.The surface of the modified SA membrane was smooth with no defects and bubbles,the interface between the TPU conductive nonwoven fabric and the SA membrane was strong.Both the thermal stability and the mechanical properties of the membrane were also improved after modification.