To raise the room temperature ionic conductivity and improve the mechanical strength of a PEO-based polymer electrolyte, a noncrystalline two-component epoxy electrolyte system has been prepared. The diglycidyl ether ...To raise the room temperature ionic conductivity and improve the mechanical strength of a PEO-based polymer electrolyte, a noncrystalline two-component epoxy electrolyte system has been prepared. The diglycidyl ether of polyethylene glycols as precursors of the system were synthesized by a two-step process. The presumed structure of the product was characterized, by ^(13)C, ~1H NMR and IR spectroscopy. It was found that a side-reaction occurred between the secondary hydroxyl group of PEG-chlorohydrin and epichlorohydrin in some degree, resulting in a by- product containing—CH_2Cl side group. By selecting a characteristic signal, which is undistorted by the increase in the length of CH_2 CH_2—O segment, a ~1H NMR approach of determining the equivalent epoxy weight (EEW) was proposed. The method is valid to specimens even though the EEW is as high as 2,000. The examination of the specimens by DSC showed that epoxidation greatly depressed the crystallinity of the PEG's, whereas the T_g was raised.展开更多
A series of new norspermidine derivatives, both nonionic and cationic, have been obtained. Structures of the synthesized compounds have been estab-lished by FTIR, 1H NMR, 13C NMR, 2D NMR, mass spectrometry and element...A series of new norspermidine derivatives, both nonionic and cationic, have been obtained. Structures of the synthesized compounds have been estab-lished by FTIR, 1H NMR, 13C NMR, 2D NMR, mass spectrometry and elemental analyses. Physicochemical and anti-microbial properties have been discussed.展开更多
The morphology of some polyetherester-ureas were studied by ^(13)C CP/MAS and ~1H wide-line NMR spectroscopy. It was found that the HDI and MDI based polymers have well crystallized hard segments, whereas the TDI and ...The morphology of some polyetherester-ureas were studied by ^(13)C CP/MAS and ~1H wide-line NMR spectroscopy. It was found that the HDI and MDI based polymers have well crystallized hard segments, whereas the TDI and HMDI based ones have not. For HDI/MDI based polymers, the presented results suggest that the distribution of two kinds of hard segment units is mainly in a block form. The influences of the different hard segment and chain length on the mobility of the soft segment were also studied.展开更多
The reaction of VCl3 with 4-（2, 4-dihydroxybenzaldimine） antipyrine （LH） in a l ： 1 molar ratio results in formation of the general complex of [VOL（CI）OH]. The nature of bonding and stereochemistry of the compl...The reaction of VCl3 with 4-（2, 4-dihydroxybenzaldimine） antipyrine （LH） in a l ： 1 molar ratio results in formation of the general complex of [VOL（CI）OH]. The nature of bonding and stereochemistry of the complex was deduced from the elemental analysis, IR, UV-Vis, 1H and ^13C NMR spectroscopy. This complex has a coordination number five （square pyramidal） as known for many vanadyl complexes. The formation of the vanadyl ion （VO^2＋） and the mode of bonding of the Schiff base through the oxygen of the pyrazol ring and the nitrogen of the azomethine group to the vanadyl ion were established by IR technique.展开更多
基金The project supported by National Natural Science Foundation of China.
文摘To raise the room temperature ionic conductivity and improve the mechanical strength of a PEO-based polymer electrolyte, a noncrystalline two-component epoxy electrolyte system has been prepared. The diglycidyl ether of polyethylene glycols as precursors of the system were synthesized by a two-step process. The presumed structure of the product was characterized, by ^(13)C, ~1H NMR and IR spectroscopy. It was found that a side-reaction occurred between the secondary hydroxyl group of PEG-chlorohydrin and epichlorohydrin in some degree, resulting in a by- product containing—CH_2Cl side group. By selecting a characteristic signal, which is undistorted by the increase in the length of CH_2 CH_2—O segment, a ~1H NMR approach of determining the equivalent epoxy weight (EEW) was proposed. The method is valid to specimens even though the EEW is as high as 2,000. The examination of the specimens by DSC showed that epoxidation greatly depressed the crystallinity of the PEG's, whereas the T_g was raised.
文摘A series of new norspermidine derivatives, both nonionic and cationic, have been obtained. Structures of the synthesized compounds have been estab-lished by FTIR, 1H NMR, 13C NMR, 2D NMR, mass spectrometry and elemental analyses. Physicochemical and anti-microbial properties have been discussed.
文摘The morphology of some polyetherester-ureas were studied by ^(13)C CP/MAS and ~1H wide-line NMR spectroscopy. It was found that the HDI and MDI based polymers have well crystallized hard segments, whereas the TDI and HMDI based ones have not. For HDI/MDI based polymers, the presented results suggest that the distribution of two kinds of hard segment units is mainly in a block form. The influences of the different hard segment and chain length on the mobility of the soft segment were also studied.
文摘The reaction of VCl3 with 4-（2, 4-dihydroxybenzaldimine） antipyrine （LH） in a l ： 1 molar ratio results in formation of the general complex of [VOL（CI）OH]. The nature of bonding and stereochemistry of the complex was deduced from the elemental analysis, IR, UV-Vis, 1H and ^13C NMR spectroscopy. This complex has a coordination number five （square pyramidal） as known for many vanadyl complexes. The formation of the vanadyl ion （VO^2＋） and the mode of bonding of the Schiff base through the oxygen of the pyrazol ring and the nitrogen of the azomethine group to the vanadyl ion were established by IR technique.
