为提高锂离子电池聚偏氟乙烯(PVDF)基聚合物隔膜对电解液体系的亲和性和导电性,引入聚甲基丙烯酸甲酯(PMMA)与聚偏氟乙烯(PVDF)进行共混,并添加有机增塑剂聚乙二醇PEG-400对PVDF基聚合物隔膜进行改性研究。采用先干法后湿法的相转化方...为提高锂离子电池聚偏氟乙烯(PVDF)基聚合物隔膜对电解液体系的亲和性和导电性,引入聚甲基丙烯酸甲酯(PMMA)与聚偏氟乙烯(PVDF)进行共混,并添加有机增塑剂聚乙二醇PEG-400对PVDF基聚合物隔膜进行改性研究。采用先干法后湿法的相转化方法制备PVDF/PMMA/PEG型聚合物隔膜。通过对制备的聚合物隔膜的孔隙率、吸液率、微观形貌和电化学性能的分析研究,确定制膜的最佳工艺条件为聚合物占溶剂质量百分比为8%,PVDF∶PMMA=7∶3,增塑剂含量为30%,非溶剂含量为3%,反应温度为45℃,在此最佳工艺条件下制备的PVDF/PMMA/PEG隔膜的离子电导率可达2.848 m S/cm,对电解液体系的亲和性和导电性得到显著提高。展开更多
In the present work, magnetite (Fe<sub>3</sub>O<sub>4</sub>) nanoparticles have been prepared by a simple chemical method. Polymer nanocomposites based on the blend between poly vinylamine fluo...In the present work, magnetite (Fe<sub>3</sub>O<sub>4</sub>) nanoparticles have been prepared by a simple chemical method. Polymer nanocomposites based on the blend between poly vinylamine fluoride (PVDF) and (methyl methacrylate) (PMMA) doped with different concentrations of Fe<sub>3</sub>O<sub>4</sub> nanoparticles have been prepared. The structural, optical, and magnetization properties of the nanocomposite samples were studied using suitable techniques. The X-ray study reflected that the cubic spinal structure of pure Fe<sub>3</sub>O<sub>4</sub> crystal. No small peaks or ripples were found in the X-ray spectra, conforming to good dispersion of Fe<sub>3</sub>O<sub>4</sub> within PVDF/PMMA matrices. The FT-IR analysis demonstrated the miscibility between the PVDF and PMMA blend with the interaction between the polymer blend and Fe<sub>3</sub>O<sub>4</sub>. The values of the band gap from UV-Vis study were decreased up to 4.21 eV, 3.01 eV for direct and indirect measurements, respectively. The magnetization was measured as a function of the applied magnetic field in the range of −2000 - 2000 Oersted. The curves of the magnetization indicated a paramagnetic behavior of pure Fe<sub>3</sub>O<sub>4</sub> nanoparticles and PVDF/PMMA-Fe<sub>3</sub>O<sub>4</sub> nanocomposites. The values of saturation magnetization for pure Fe<sub>3</sub>O<sub>4</sub> are nearly 75 emu/g, exhibiting a paramagnetic behavior, and it is decreased with the increase of Fe<sub>3</sub>O<sub>4</sub> content.展开更多
采用溶剂挥发法,以丙酮和DMF做混合溶剂制备PVDF-HFP/PMMA聚合物电解质,通过X射线衍射、热失重分析、交流阻抗、恒流充放电循环及倍率充放电等测试手段,考察了PMMA的添加量对聚合物电解质性能的影响.研究发现当PMMA的添加量为50%时,聚...采用溶剂挥发法,以丙酮和DMF做混合溶剂制备PVDF-HFP/PMMA聚合物电解质,通过X射线衍射、热失重分析、交流阻抗、恒流充放电循环及倍率充放电等测试手段,考察了PMMA的添加量对聚合物电解质性能的影响.研究发现当PMMA的添加量为50%时,聚合物电解质表现出最佳性能,室温离子电导率从0.26 m S/cm提升到1.35 m S/cm,以Li Co O2作正极材料,锂片作负极材料组装的聚合物锂离子电池初始容量从80.1 m Ah/g提升到143.6 m Ah/g,在0.2 C倍率条件下,50个循环后容量保持率还能达到80%,表现出优异的锂离子电池性能.展开更多
文摘采用机械共混法制备了Si O2改性的CPVC/PVDF/PMMA复合材料,考察了Si O2用量、PVB、PVC、丁腈粉、DBP对材料成膜性能、吸墨性能、柔软性和韧性的影响.结果表明:1当Si O2的质量浓度为4.5%时,CPVC的成膜性和吸墨性能最佳;2当DBP、丁腈粉的质量分数分别为3.0%和3.4%时,膜的柔韧性最佳;3最佳的制备工艺是将PMMA、CPVC、PVDF和丁腈粉溶于DMAC和DBP的混合溶液中,再恒温4 h.
文摘为提高锂离子电池聚偏氟乙烯(PVDF)基聚合物隔膜对电解液体系的亲和性和导电性,引入聚甲基丙烯酸甲酯(PMMA)与聚偏氟乙烯(PVDF)进行共混,并添加有机增塑剂聚乙二醇PEG-400对PVDF基聚合物隔膜进行改性研究。采用先干法后湿法的相转化方法制备PVDF/PMMA/PEG型聚合物隔膜。通过对制备的聚合物隔膜的孔隙率、吸液率、微观形貌和电化学性能的分析研究,确定制膜的最佳工艺条件为聚合物占溶剂质量百分比为8%,PVDF∶PMMA=7∶3,增塑剂含量为30%,非溶剂含量为3%,反应温度为45℃,在此最佳工艺条件下制备的PVDF/PMMA/PEG隔膜的离子电导率可达2.848 m S/cm,对电解液体系的亲和性和导电性得到显著提高。
文摘In the present work, magnetite (Fe<sub>3</sub>O<sub>4</sub>) nanoparticles have been prepared by a simple chemical method. Polymer nanocomposites based on the blend between poly vinylamine fluoride (PVDF) and (methyl methacrylate) (PMMA) doped with different concentrations of Fe<sub>3</sub>O<sub>4</sub> nanoparticles have been prepared. The structural, optical, and magnetization properties of the nanocomposite samples were studied using suitable techniques. The X-ray study reflected that the cubic spinal structure of pure Fe<sub>3</sub>O<sub>4</sub> crystal. No small peaks or ripples were found in the X-ray spectra, conforming to good dispersion of Fe<sub>3</sub>O<sub>4</sub> within PVDF/PMMA matrices. The FT-IR analysis demonstrated the miscibility between the PVDF and PMMA blend with the interaction between the polymer blend and Fe<sub>3</sub>O<sub>4</sub>. The values of the band gap from UV-Vis study were decreased up to 4.21 eV, 3.01 eV for direct and indirect measurements, respectively. The magnetization was measured as a function of the applied magnetic field in the range of −2000 - 2000 Oersted. The curves of the magnetization indicated a paramagnetic behavior of pure Fe<sub>3</sub>O<sub>4</sub> nanoparticles and PVDF/PMMA-Fe<sub>3</sub>O<sub>4</sub> nanocomposites. The values of saturation magnetization for pure Fe<sub>3</sub>O<sub>4</sub> are nearly 75 emu/g, exhibiting a paramagnetic behavior, and it is decreased with the increase of Fe<sub>3</sub>O<sub>4</sub> content.
文摘采用溶剂挥发法,以丙酮和DMF做混合溶剂制备PVDF-HFP/PMMA聚合物电解质,通过X射线衍射、热失重分析、交流阻抗、恒流充放电循环及倍率充放电等测试手段,考察了PMMA的添加量对聚合物电解质性能的影响.研究发现当PMMA的添加量为50%时,聚合物电解质表现出最佳性能,室温离子电导率从0.26 m S/cm提升到1.35 m S/cm,以Li Co O2作正极材料,锂片作负极材料组装的聚合物锂离子电池初始容量从80.1 m Ah/g提升到143.6 m Ah/g,在0.2 C倍率条件下,50个循环后容量保持率还能达到80%,表现出优异的锂离子电池性能.
