With the natural rosin derivative （maleopimaric acid, MPA） as the raw material, imide modified vinyl poly（dimethylsiloxane） （MP-VMS） was synthesized and characterized by ^1H NMR and ^13C NMR. The curing kinetic ...With the natural rosin derivative （maleopimaric acid, MPA） as the raw material, imide modified vinyl poly（dimethylsiloxane） （MP-VMS） was synthesized and characterized by ^1H NMR and ^13C NMR. The curing kinetic parameters of MP-VMS were determined by differential scanning calorimetry （DSC） at various heating rates （5, 8, 10, 15 ℃/min） from the Kissingner, Ozawa and Crane methods. The activation energy （Ea）, pre-exponential factor （A） and reaction order （n） were respectively 18.6 kJ/mol, 71,108 and 0.902. The low-temperature and high-temperature resistance of its curing product were respectively investigated by DSC and thermogravimetric analysis. The results showed that incorporation of MPA could significantly improve the thermal stability of silicone while had no effect on the low-temperature resistance, and the Tmax （the temperature corresponding to the maximum weight loss rate） increased by 70.7 ℃.展开更多
Sodium-ion batteries(SIBs)are considered one of the most promising energy storage systems for replacing lithium-ion batteries because of the high abundance and low cost of sodium.Iron oxyfluoride(FeOF)is a promising c...Sodium-ion batteries(SIBs)are considered one of the most promising energy storage systems for replacing lithium-ion batteries because of the high abundance and low cost of sodium.Iron oxyfluoride(FeOF)is a promising conversion-based cathode material for SIBs because of its high theoretical capacity of about855 mA h g^(-1),low-cost chemical compositions,and its lower sensitivity to the size of charged carrier ions.However,the poor electrical conductivity and ionic diffusion of FeOF result in a low rate capability and cyclability.In this work,FeOF nanoparticles wrapped by graphitic carbon layers were synthesized using abietic or maleopimaric acid as both the carbon source and organic ligand.In addition,the morphology of the FeOF particles was gradually controlled from rod to spherical shapes,simply depending on the rosin acids.The FeOF nanoparticles prepared with maleopimaric acid showed a large reversible discharge capacity of 356.7 mA h g^(-1)with a fading rate of 0.21%per cycle after 100 cycles at a current density of 100 mA g^(-1)and an excellent rate capability.展开更多
基金supported by the National Natural Science Foundation of China(No.31200446)
文摘With the natural rosin derivative （maleopimaric acid, MPA） as the raw material, imide modified vinyl poly（dimethylsiloxane） （MP-VMS） was synthesized and characterized by ^1H NMR and ^13C NMR. The curing kinetic parameters of MP-VMS were determined by differential scanning calorimetry （DSC） at various heating rates （5, 8, 10, 15 ℃/min） from the Kissingner, Ozawa and Crane methods. The activation energy （Ea）, pre-exponential factor （A） and reaction order （n） were respectively 18.6 kJ/mol, 71,108 and 0.902. The low-temperature and high-temperature resistance of its curing product were respectively investigated by DSC and thermogravimetric analysis. The results showed that incorporation of MPA could significantly improve the thermal stability of silicone while had no effect on the low-temperature resistance, and the Tmax （the temperature corresponding to the maximum weight loss rate） increased by 70.7 ℃.
基金supported by the Dong-A University research fund。
文摘Sodium-ion batteries(SIBs)are considered one of the most promising energy storage systems for replacing lithium-ion batteries because of the high abundance and low cost of sodium.Iron oxyfluoride(FeOF)is a promising conversion-based cathode material for SIBs because of its high theoretical capacity of about855 mA h g^(-1),low-cost chemical compositions,and its lower sensitivity to the size of charged carrier ions.However,the poor electrical conductivity and ionic diffusion of FeOF result in a low rate capability and cyclability.In this work,FeOF nanoparticles wrapped by graphitic carbon layers were synthesized using abietic or maleopimaric acid as both the carbon source and organic ligand.In addition,the morphology of the FeOF particles was gradually controlled from rod to spherical shapes,simply depending on the rosin acids.The FeOF nanoparticles prepared with maleopimaric acid showed a large reversible discharge capacity of 356.7 mA h g^(-1)with a fading rate of 0.21%per cycle after 100 cycles at a current density of 100 mA g^(-1)and an excellent rate capability.
