The complexation reaction between borate ions and phenol-formaldehyde resol resin in aqueous solution was studied by pH measurement, small model molecules and infrared spectroscopy. The results show that the complexat...The complexation reaction between borate ions and phenol-formaldehyde resol resin in aqueous solution was studied by pH measurement, small model molecules and infrared spectroscopy. The results show that the complexation can proceed completely and rapidly at room temperature. Borate ion attacks phenol hydroxyl groups and adjacent position hydroxymethyl groups on the phenol ring of the resin, and forms the coordinate bond between boron atom in borate ion and oxygen atom in the hydroxyl groups. The complexation is a quantitative reaction. The complex is a six member ring containing two oxygens and one boron. The complexation can release hydrogen ions resulting in the decreasing pH in the resin solution.展开更多
Carhons were prepared at different temperatures by pyrolytic treatment of phenolformaldehyde resin molded with ZnCl2 in advance. X-ray structure analyses have shown that these carbon are essentially amorphous with rat...Carhons were prepared at different temperatures by pyrolytic treatment of phenolformaldehyde resin molded with ZnCl2 in advance. X-ray structure analyses have shown that these carbon are essentially amorphous with rather loose structure of molecular size order with an interlayer distance of 0.36—0.37 nm. Using electrochemical methods, we have studied the insertion of lithium within these materials. Resole resins, heated to 580 ℃, have a reversible capacity of about 400 mA·h/g, which is beyond the theoretical capacity of graphite（372 mA·h/g） and discover that carbons with a smaller crystallite size and large interlayer distance have the larger discharge capacity.展开更多
文摘The complexation reaction between borate ions and phenol-formaldehyde resol resin in aqueous solution was studied by pH measurement, small model molecules and infrared spectroscopy. The results show that the complexation can proceed completely and rapidly at room temperature. Borate ion attacks phenol hydroxyl groups and adjacent position hydroxymethyl groups on the phenol ring of the resin, and forms the coordinate bond between boron atom in borate ion and oxygen atom in the hydroxyl groups. The complexation is a quantitative reaction. The complex is a six member ring containing two oxygens and one boron. The complexation can release hydrogen ions resulting in the decreasing pH in the resin solution.
文摘Carhons were prepared at different temperatures by pyrolytic treatment of phenolformaldehyde resin molded with ZnCl2 in advance. X-ray structure analyses have shown that these carbon are essentially amorphous with rather loose structure of molecular size order with an interlayer distance of 0.36—0.37 nm. Using electrochemical methods, we have studied the insertion of lithium within these materials. Resole resins, heated to 580 ℃, have a reversible capacity of about 400 mA·h/g, which is beyond the theoretical capacity of graphite（372 mA·h/g） and discover that carbons with a smaller crystallite size and large interlayer distance have the larger discharge capacity.
