多元酸交联聚乙烯醇渗透汽化膜

研究了交联聚乙烯醇(PVA)渗透汽化膜。所用交联剂包括:马来酸酐、草酸、柠檬酸、偏苯三酸酐、邻苯二甲酸酐及1.6己二酸。渗透汽化的结果表明,交联剂的结构对渗透汽化膜的性能有很大的影响。当使用同样当量交联剂时,交联剂的官能度越大,当量越小,膜的分离系数越大而流量越小。交联剂分子中芳香基的存在导致流量增大,分离系数下降。交联膜的热分析结果进一步证实了交联剂结构对选择分离性能的影响。

PVA Pervaporation Membrane Crosslinked by Multinary Acid

The crosslinked poly (vinyl alcohol) (PVA) membrane was investigated as the pervapo-ration membrane. The crosslinking agents included maleic anhydride,oxalic acid,citric acid, trimellitic anhydride ,o-phthalic anhydride and 1. 6-hexane diacid. The pervaporation results showed the structure of crosslinking agent exerted a great influence on the performance of the pervaporation membrane. The more the functionality and the less the equivalent of crosslinking agent was,the larger the separation factor and the less flux of the membrane, when same equivalent of crosslinking agent was used. The presence of aryl residue in crosslinking agent molecular resulted in the increase of flux and the decrease of separation factor. The permselectivity change was caused by the structure of crosslinking agent and was confirmed by the thermoanalysis of crosslinked membrane.