Four common types of additives for polymer membrane preparation including organic macromolecule and micromolecule additives, inorganic salts and acids, and the strong non-solvent H2 O were used to prepare poly（vinyli...Four common types of additives for polymer membrane preparation including organic macromolecule and micromolecule additives, inorganic salts and acids, and the strong non-solvent H2 O were used to prepare poly（vinylidene fluoride-co-chlorotrifluoroethylene）（PVDF-CTFE） hydrophobic flat-sheet membranes. Membrane properties including morphology, porosity, hydrophobicity, pore size and pore distribution were investigated, and the permeability was evaluated via direct contact membrane distillation（DCMD） of 3.5 g/L Na Cl solution in a DCMD configuration. Both inorganic and organic micromolecule additives were found to slightly influence membrane hydrophobicity. Polyethylene glycol（PEG）,organic acids, Li Cl, Mg Cl2, and Li Cl/H2 O mixtures were proved to be effective additives to PVDF-CTFE membranes due to their pore-controlling effects and the capacity to improve the properties and performance of the resultant membranes. The occurrence of a pre-gelation process showed that when organic and inorganic micromolecules were added to PVDF-CTFE solution, the resultant membranes presented a high interconnectivity structure. The membrane prepared with dibutyl phthalate（DBP） showed a nonporous surface and symmetrical cross-section. When H2 O and Li Cl/H2 O mixtures were also used as additives, they were beneficial for solid–liquid demixing, especially when Li Cl/H2 O mixed additives were used. The membrane prepared with 5% Li Cl ＋ 2% H2 O achieved a flux of24.53 kg/（m2·hr） with 99.98% salt rejection. This study is expected to offer a reference not only for PVDF-CTFE membrane preparation but also for other polymer membranes.展开更多
文摘采用并列电纺技术制备了具有并列结构的Sb_(2)O_(3)@PMIA/TPP@PVDF-CTFE锂离子电池复合隔膜,对复合隔膜的力学性能、热稳定性能、阻燃性能、电解液润湿性等性能进行分析测试。结果表明,复合隔膜具有较高的力学性能(拉伸强度为11.7 MPa),优异的热稳定性(220℃下热处理0.5 h后只有略微形变),良好的阻燃性能和优异的电解液润湿性,且其孔隙率和吸液率也较高(分别为277%、78%),离子电导率也高达2.67 m S/cm,表明制备的并列结构复合隔膜有效的提高了电池的安全性与离子传输能力。
基金Financial support by the National Natural Science Foundation of China (Nos. 51378491, 51578533, 21307149) is also gratefully acknowledged
文摘Four common types of additives for polymer membrane preparation including organic macromolecule and micromolecule additives, inorganic salts and acids, and the strong non-solvent H2 O were used to prepare poly（vinylidene fluoride-co-chlorotrifluoroethylene）（PVDF-CTFE） hydrophobic flat-sheet membranes. Membrane properties including morphology, porosity, hydrophobicity, pore size and pore distribution were investigated, and the permeability was evaluated via direct contact membrane distillation（DCMD） of 3.5 g/L Na Cl solution in a DCMD configuration. Both inorganic and organic micromolecule additives were found to slightly influence membrane hydrophobicity. Polyethylene glycol（PEG）,organic acids, Li Cl, Mg Cl2, and Li Cl/H2 O mixtures were proved to be effective additives to PVDF-CTFE membranes due to their pore-controlling effects and the capacity to improve the properties and performance of the resultant membranes. The occurrence of a pre-gelation process showed that when organic and inorganic micromolecules were added to PVDF-CTFE solution, the resultant membranes presented a high interconnectivity structure. The membrane prepared with dibutyl phthalate（DBP） showed a nonporous surface and symmetrical cross-section. When H2 O and Li Cl/H2 O mixtures were also used as additives, they were beneficial for solid–liquid demixing, especially when Li Cl/H2 O mixed additives were used. The membrane prepared with 5% Li Cl ＋ 2% H2 O achieved a flux of24.53 kg/（m2·hr） with 99.98% salt rejection. This study is expected to offer a reference not only for PVDF-CTFE membrane preparation but also for other polymer membranes.
