In this study, a series of flame-retardant polyisocyanurate-polyurethane (PIR-PUR) foams were prepared using various concentrations (0-25% by weight) of expandable graphite (EG) and dimethyl methyl phosphonate (DMMP) ...In this study, a series of flame-retardant polyisocyanurate-polyurethane (PIR-PUR) foams were prepared using various concentrations (0-25% by weight) of expandable graphite (EG) and dimethyl methyl phosphonate (DMMP) (0-7% by weight). The effect of these additives on the properties of the PIR-PUR foams, including physico-mechanical, morphological, flame retardancy, and thermal stability, was studied. Increasing amounts of EG in the PIR-PUR foam caused a significant drop in the compression strength. However, DMMP caused the mechanical properties of PIR-PUR foam to improve compared to foam filled with EG alone. The flame retardancy of PIR-PUR foams containing both EG and DMMP was enhanced significantly compared to EG filled foams. Thermogravimetric analysis (TGA) indicated that EG enhances the thermal stability of PIR-PUR foams but that DMMP decreased it. The morphology of the residual char provided conclusive evidence for the weak thermal stability of foams filled with DMMP.展开更多
To improve the safety of lithium-ion batteries,dimethyl methyl phosphonate(DMMP) was used as a flame-retardant additive in a LiPF6 electrolyte solution. The flammability and thermal stability of DMMP-containing electr...To improve the safety of lithium-ion batteries,dimethyl methyl phosphonate(DMMP) was used as a flame-retardant additive in a LiPF6 electrolyte solution. The flammability and thermal stability of DMMP-containing electrolyte was investigated by means of burning test and accelerating rate calorimeter. It was found that the flammability and self-heat rate of the electrolyte can be reduced by the addition of DMMP. On the other hand,the electrochemical performances of graphite/LiCoO2 cells become slightly worse after using DMMP additive in the electrolyte. This alleviated trade-off between electrolyte flammability,thermal stability,and cell performance provides a possibility to formulate a nonflammable electrolyte containing DMMP and improve the electrolyte thermal stability with a minimal sacrifice in performance.展开更多
基金supported by the State Key Program of Coal Joint Funds of National Natural Science Foundation of China (No.51134020)the Natural Science Foundation of Shandong Province(No. ZR2011EL036)the High School Science & Technology Fund Planning Project of Shandong Province (No. JIILD53)
文摘In this study, a series of flame-retardant polyisocyanurate-polyurethane (PIR-PUR) foams were prepared using various concentrations (0-25% by weight) of expandable graphite (EG) and dimethyl methyl phosphonate (DMMP) (0-7% by weight). The effect of these additives on the properties of the PIR-PUR foams, including physico-mechanical, morphological, flame retardancy, and thermal stability, was studied. Increasing amounts of EG in the PIR-PUR foam caused a significant drop in the compression strength. However, DMMP caused the mechanical properties of PIR-PUR foam to improve compared to foam filled with EG alone. The flame retardancy of PIR-PUR foams containing both EG and DMMP was enhanced significantly compared to EG filled foams. Thermogravimetric analysis (TGA) indicated that EG enhances the thermal stability of PIR-PUR foams but that DMMP decreased it. The morphology of the residual char provided conclusive evidence for the weak thermal stability of foams filled with DMMP.
基金Projects(2006A10704003 2006Z3-D2031) supported by the Key Project of Guangdong Province and Guangzhou City, China
文摘To improve the safety of lithium-ion batteries,dimethyl methyl phosphonate(DMMP) was used as a flame-retardant additive in a LiPF6 electrolyte solution. The flammability and thermal stability of DMMP-containing electrolyte was investigated by means of burning test and accelerating rate calorimeter. It was found that the flammability and self-heat rate of the electrolyte can be reduced by the addition of DMMP. On the other hand,the electrochemical performances of graphite/LiCoO2 cells become slightly worse after using DMMP additive in the electrolyte. This alleviated trade-off between electrolyte flammability,thermal stability,and cell performance provides a possibility to formulate a nonflammable electrolyte containing DMMP and improve the electrolyte thermal stability with a minimal sacrifice in performance.
