The chemical composition, molecular weight and its distribution, the bonding structure and the regulation of ultrahigh molecular weight polyacrylonitrile （UHMW-PAN） prepared by aqueous suspension polymerization were...The chemical composition, molecular weight and its distribution, the bonding structure and the regulation of ultrahigh molecular weight polyacrylonitrile （UHMW-PAN） prepared by aqueous suspension polymerization were determined by FIIR, viscometry, GPC, ^3H-NMR and ^13CNMR. The mechanical properties of the porous hollow fiber prepared by UHMW-PAN were discussed to provide a theoretical basis for the preparation of ideal precursors of the porous hollow oxidation fiber.展开更多
High-temperature coal tar was extracted with petroleum ether （PE） under ultrasonic irradiation and the extracts were analyzed with gas chromatograph/mass spectrometer. The acearylene fractions including acenaphthyle...High-temperature coal tar was extracted with petroleum ether （PE） under ultrasonic irradiation and the extracts were analyzed with gas chromatograph/mass spectrometer. The acearylene fractions including acenaphthylene, aceanthrylene and cyclopentapyrene were enriched together and named E, which was then transferred to a car- tridge in Isolera-One flash chromatography. Three groups of compounds were eluted out with ethyl acetate/PE mixed solvent （volume ratio 1：9） and named E1, E2 and E3 according to their main components. Acenaphthylene accounted for 78.2% in El, aceanthrylene 71.6% in E2 and cyclopentapyrene 75.9% in E3, respectively. The three groups of acearylenes were purified by Sephadex LH-20 column chromatography with ethanol/cyclohexane mixed solvent （vol- ume ratio 1：4）, and then confirmed with nuclear magnetic resonance spectrometer. This method indicates that flash chromatography has a good effect on separating the compounds with a similar structnre after extraction under ultrasonic irradiation.展开更多
文摘The chemical composition, molecular weight and its distribution, the bonding structure and the regulation of ultrahigh molecular weight polyacrylonitrile （UHMW-PAN） prepared by aqueous suspension polymerization were determined by FIIR, viscometry, GPC, ^3H-NMR and ^13CNMR. The mechanical properties of the porous hollow fiber prepared by UHMW-PAN were discussed to provide a theoretical basis for the preparation of ideal precursors of the porous hollow oxidation fiber.
基金Supported by National Natural Science Foundation of China for Innovative Research Group(No.50921002)the Program of the Universities in Jiangsu Province for Development of High-Tech Industries(No.JHB05-33)the Fundamental Research Funds for the Central Universities (China University of Mining and Technology,No.2010ZDP02B03)
文摘High-temperature coal tar was extracted with petroleum ether （PE） under ultrasonic irradiation and the extracts were analyzed with gas chromatograph/mass spectrometer. The acearylene fractions including acenaphthylene, aceanthrylene and cyclopentapyrene were enriched together and named E, which was then transferred to a car- tridge in Isolera-One flash chromatography. Three groups of compounds were eluted out with ethyl acetate/PE mixed solvent （volume ratio 1：9） and named E1, E2 and E3 according to their main components. Acenaphthylene accounted for 78.2% in El, aceanthrylene 71.6% in E2 and cyclopentapyrene 75.9% in E3, respectively. The three groups of acearylenes were purified by Sephadex LH-20 column chromatography with ethanol/cyclohexane mixed solvent （vol- ume ratio 1：4）, and then confirmed with nuclear magnetic resonance spectrometer. This method indicates that flash chromatography has a good effect on separating the compounds with a similar structnre after extraction under ultrasonic irradiation.
