Construction Of New Crosslinking Modified Pervaporation Film Based On Macrocyclic Compounds And Its Properties

With the development of membrane technology in recent years, it has been one of the common support technology to solve many problems about the energy and environment, and how to construct the special and high performance PV membrane in the complex organic environment has attracted much attention.For the purpose of desulfurization from fuel oil, this paper put forward a new thought with the polyrotaxane and construct a novel pervaporation, the research can provide some reference about the membrane preparation and modification facing to the separation of complex organisms such as fuel oil. The main research contents and work are as follows:(1) Using CD and the modification of polyrotaxane glycol as host and guest respectively, inclusion compound was forming through the host-guest supramolecular forces between the molecules,finally, polyrotaxane was accessible after the process of blocking. Using the reaction of the large number of active hydroxyl of CDs in the polyrotaxane with allyl glycidyl ether, the polyrotaxane cross-linking agent was obtained. A series of characterization methods such as infrared spectrum, NMR, and X-ray diffraction verified the success preparation of the product.(2) Respectively using the traditional cross-linking agent pentaerythritol triacrylate, homemade CD cross-linking agent and polyrotaxane cross-linking agent to modify the membrane, and some characterization methods such as SEM, TG, swelling degree test were used to verify the performance of the crossinked membrane, and the results are as follows:polyrotaxane crosslinked membranes had homogeneous and continuous structure, and also good mechanical properties and thermal stability. The swelling tests confirmed that polyrotaxane crosslinked membranes had excellent adsorption ability on thiophene, which was better than PETA and CD crossinked membrane. The test of membrane density and crosslinking density showed that polyrotaxane cross-linking agent had excellent effects on the membrane, the polyrotaxane crosslinked membrane’s density increased greatly.(3) The PV desulfurization tests were implemented using the polyrotaxane crosslinked membrane, and the influence of membrane desulfurization performance with the temperature, the Content of crosslinking agent and the liquid composition had been discussed. The results showed that polyrotaxane crosslinked membranes have excellent desulfurization performance comparing with PETA crosslinked membranes, which had a great improvement in flux. Higher temperature and the adding of toluene made the membrane’s flux increase significantly, but no change with the separation factor. With the polyrotaxane cross-linking agent amount of 5%, it achieved a better membrane separation performance, the total permeation flux was 1500g·m-2·h-1, and the sulfer enrichment factor came to 5.0.(4) A molecularly imprinted polymer for thiophene was prepared, and a novel molecularly imprinted composite membrane was made to combine with the membrane. Then using the novel composite membrane for the test of PV desulfurization, and to explore the influence of different conditions. The results are as follows:molecularly imprinted composite membranes had good mechanical properties and thermal stability. It had better selectivity for thiophene, and the composite membrane’s separation factor increased. The temperature and liquid composition had effects on the PV desulfurization of the composite membranes. With the rising of the temperature, the flux also increased, but the separation factor showed the tendency of decrease. The addition of toluene made the composite membrane’s flux increased.