| PolyTHF is a kind of straight-chain polyether diols, prepared by cationic ring-opening polymerization from tetrahydrofuran. As a versatile intermediate in synthetic spandex, polyurethane and polyether ester elastomers, it is widely applied in the chemical industry, textile, automotive, medical equipment, military equipment and other fields. The product quality dependent on the catalyst performance for the polymerization of THF. Nowadays, the development of environmentally friendly technology for THF polymerization has become the research focus.MCM-41 is known to be a type of mesoporous silica with a uniform hexagonal array of cylindrical mesopores along with a very high surface area and hence is expected to be suitable as a catalytic material, particularly for the preparation of large molecules. But the pure silicon MCM-41 have low acid. However, to be catalytically active such silica MCM-41 molecular sieves are modified to create active sites.Two sets of modified MCM-41 solid acid catalysts were prepared and characterized by N2 adsorption-desorption, XRD, FT-IR, NH3-TPD, Py-IR. the influence of catalytic performances of different materials on the products yields and number average molecular weight in the polymerization reaction of THF were investigated.1. A series of mesoporous Al-MCM-41 with different Si/Al ratios were prepared by hydrothermal method. The results showed that the obtained Al-MCM-41 samples were well-ordered and have the similar porous texture with mesoporous molecular. Although both Brφnsted and Lewis acid sites were observed from Py-IR., the latter were primary. The Al-MCM-41 materials were applied to the polymerization of tetrahydrofuran (THF). It was found that the activity of the solid acids increased with the increase of alumina content and then decreased gradually, reached optimal when the Si/Al ratio was 30 and the number average molecular weight of the polyoxytetramethyleneglycol (PTMEG) was around 1000. The optimal condition of the polymerization of THF was obtained when the Si/Al ratio, was 30, reaction temperature 40℃and reaction time 6 h, respectively. At this condition, the yield of the PTHF reached 22%, the number average molecular weight was 1000, and the production was used as the raw materials of Rubber, conveyor belts, hoses, etc.2. HPW/MCM-41 samples with different HPW loadings were synthesized by wetness impregnation method. The results showed the supported catalysts retained the Keggin structure and well dispersed on the MCM-41 surface. The HPW crystal phase was observed at the loadings of 50%. Only Brφnsted acid sites were observed from Py-IR. The HPW/MCM-41 materials were applied to the polymerization of THF. It was found that the yield was around 50%, and the number average molecular weight was around 2000 when the loading of HPW was 50%. The production obtained with the catalyst of HPW/MCM-41 was the preferred materials of Spender.3. The evolution results show that both catalysts have favorable catalytic activity. The product yield and number average molecular weight were affected by acid amount and acid type respectively. The yield was lower and the number average molecular weight was around 1000 when Al-MCM-41 was used as reaction catalyst because of its less acid amount and dominant Lewis acid site, while HPW/MCM-41 that has more acid amount and dominant Brφnsted acid site was used to obtain higher product yield and number average molecular weight around 2000.
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