论文部分内容阅读
The 12-phosphotungstic heteropolyacid(HPW)was immobilized on the surface of a silica carrier modified by the amine groups of organosilaneγ-aminopropyl triethoxysilane(APTES),and its catalytic performance was investigated for tetrahydrofuran(THF) ring-opening polymerization.This amine-functionalized catalyst exhibited better activity,and the polytetramethylene ether glycol (PTMG)yield was 63.7%.The 12-phosphotungstic heteropolyacid supported on aminopropyl-functionalized SiO2 support (HPW/SiO2-APTES)was reused four times and showed a good maintenance of activity which was better than that of the conventional catalyst HPW supported on SiO2(HPW/SiO2).These results were obtained using infrared spectroscopy,nuclear magnetic resonance spectroscopy,nitrogen adsorption and X-ray diffraction.HPW on the HPW/SiO2-APTES catalyst exhibited higher dispersed state and maintained a more stable structure than that of the HPW/SiO2 sample.
The 12-phosphotungstic heteropolyacid (HPW) was immobilized on the surface of a silica carrier modified by the amine groups of organosilane gamma-aminopropyl triethoxysilane (APTES), and its catalytic performance was investigated for tetrahydrofuran (THF) ring-opening polymerization.This amine- functionalized catalyst supported better activity, and the polytetramethylene ether glycol (PTMG) yield was 63.7%. The 12-phosphotungstic heteropolyacid supported on aminopropyl-functionalized SiO2 support (HPW / SiO2- APTES) was reused four times and showed a good maintenance of activity which was better than that of the conventional catalyst HPW supported on SiO2 (HPW / SiO2) .These results obtained using infrared spectroscopy, nuclear magnetic resonance spectroscopy, nitrogen adsorption and X-ray diffraction diffraction. HPW on the HPW / SiO2-APTES catalyst discloses higher dispersed state and maintained a more stable structure than that of the HPW / SiO2 sample.