Study On A New Kind Of Ion-recognized Smart Membrane

This paper selected benzo 15-crown-5 as the base unit to synthesize two kinds of crown ether compounds which named 2-hydroxymethyl-[1,4,7,10,13-pentaoxa benzo cyclo pentadecane]-3,4-5-tris [4-(10-dodecyl-1-oxo)benzyloxy]benzoate and 2-(1-methyl hydroxymethyl)-[1,4,7,10,13,-pentaoxa benzo cyclo pentadecane]-3,4,5-tris[4-(10-undecen-1-oxo) enzyloxy]benzoate, as function materials. In order to obtain a cheaper and easier synthesized function material, two kinds of base units were chosen: calix[4]arene and synthesized poly(styrene-co-allyl oxygen)-4-tert-butyl-calix [4] arene. The chemical composition and structure of the three function materials were characterized by FT-IR,1H NMR, MS, DSC and POM.For grafting function materials to the surface of supporting membrane, ultraviolet-grafting technology was selected, and the optimal reaction parameters were summarized in a number of experiments. In this way, three smart membranes with self-assembly ion channel were prepared. The membrane mircroscopic structure was characterized by ATR-FTIR, SEM, AFM and SPM.The ion transport test equipment was designed to test the ion-recognized fuction of the smart membranes. After the ion transport experiments, the data confirmed that membrane A can recognize and transport Na+, the average Na+permeation rate is 16.68×10-6cm/s and the Na+separation factor was 5.96. Compared with membrane A, membrane B had the better ion recognition capacity and ion transport capacity. The Na+permeation rate of membrane B was 53.04×10-6cm/s, and its Na+separation factor was 11.19. Both membrane A and membrane B were Na+recognized smart membranes.The Na+transport capacity of membrane C just between membrane A and B, its Na+permeation rate was 40.44×10-6cm/s. But the ion recognition capacity was better than both of them, the Na+ separation factor of membrane C was 11.69. Besides, the membrane C had K+recognize capacity and transport capacity which membrane A and membrane B did not have. The K+separation factor of membrane C was 197.68×10-6cm/s. It was much better than the transport capacity of any other ions. The K+recognize capacity of membrane C was also great than other ions, the K+separation factor was 105.15. All the data showed that membrane C was a kind of ion-recognized smart membrane which can recognize and transport both K+and Na+.