A series of X-POD polymers were prepared by condensation reaction of terephthalic dihydrazide and four different polycarboxylic acids in polyphosphoric acid (PPA) as solvent, and the corresponding membranes were formed by phase inversion method. The modified X-POD polymer structures have changed from linear structure to multidimensional network structure, which has great influence on the quality and performance of the membranes. The membrane structures were characterized by FTIR, and the thermal stability of the samples was determined by Thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC). The ultraviolet transmittance and fluorescence properties of membranes were tested by ultraviolet spectrophotometer. The crystallinity and orientation of the samples were observed by X-ray diffraction (XRD). The surface and cross-sectional morphology of the membranes were evaluated by scanning electron microscope (SEM). Additionally, the oxidation and water absorption properties of the membranes were collected, and the mechanical properties of the membranes were tested. Overall, X-POD membranes show good mechanical properties, chemical inertness and thermal stability. The quality and mechanical properties of X-POD membranes demonstrated varying degrees of improvement. Notably, the mechanical properties of II-POD and III-POD membranes were enhanced by 244.52% and 203.66%, respectively. X-POD membranes exhibit high strength and excellent toughness, rendering them a highly promising material for membrane applications in the market.

以对苯二甲酸二酰肼和四种不同的多元羧酸在聚磷酸（PPA）为溶剂中进行缩合反应制备了一系列X-POD聚合物，并通过相转化法形成了相应的膜。改性后的X-POD聚合物结构由线性结构转变为多维网络结构，对膜的质量和性能产生很大影响。通过FTIR对膜结构进行表征，并通过热重分析（TGA）和差示扫描量热计（DSC）测定样品的热稳定性。采用紫外分光光度计测试膜的紫外透过率和荧光性能。通过X射线衍射(XRD)观察样品的结晶度和取向。通过扫描电子显微镜（SEM）评估膜的表面和横截面形貌。此外，还收集了膜的氧化和吸水性能，并测试了膜的机械性能。总体而言，X-POD膜表现出良好的机械性能、化学惰性和热稳定性。X-POD膜的质量和机械性能得到了不同程度的改善。值得注意的是，II-POD和III-POD膜的机械性能分别提高了244.52%和203.66%。X-POD膜具有高强度和优异的韧性，使其成为市场上极具前景的膜应用材料。