新型聚醚砜-聚氧化乙烯共聚物的制备及锂离子传导性能研究

Synthesis and lithium ionic conductivity of novel poly(ether sulfone)-poly(ethylene oxide)copolymers

探讨了聚醚砜-聚氧化乙烯共聚物的制备方法及其锂离子传导性能。首先通过聚乙二醇和二氯亚砜反应制得氯封端的聚氧化乙烯（PEO-Cl2），然后将PEO—Cl2与三种不同结构的二元酚和4，4’-二氯二苯砜（DCDPS）在碳酸钾、甲苯存在下，以N，N-二甲基乙酰胺（DMAc）作为溶剂，进行缩聚反应，制得共聚物，并通过红外光谱和核磁共振谱图进行了表征。所制得的聚醚砜一聚氧化乙烯共聚物薄膜均有着较高的断裂伸长率和拉伸强度。XRD测试结果表明这些电解质膜在室温下具有无定形结构。以聚醚砜一聚氧化乙烯共聚物为基体，三（氟甲基磺酰）亚胺锂（LiTFSI）为掺杂剂，以1，4-丁二腈（SN）为增塑剂，研究了锂盐的掺杂量对锂离子电导率的影响，测试结果表明这些电解质膜在80℃下具有较高的锂离子电导率（6．4×10^-5～5．30×10^-4／cm）。

A series of poly（ether sultone）-poly（ethylene oxide）copolymers were synthesized and their thermal sta- bility,lithium salt doping,lithium ion conductivity and mechanical properties were investigated. The synthesis was achieved by condensation polymerization of 4,4 ＇-dichlorodiphenyl sulfone（DCDPS）, chlorine-terminated poly（ethylene oxide）（PEO- Cl2 ）prepared by the reaction of PEG and thionyl chloride, and dibasic phenols in dimethylacetamide（DMAC）in the presence of K2CO3. The copolymers were structurally characterized by FT-IR and 1H NMR spectra. The copolymer membranes showed high tensile stress and very large elongation at break. XRD patterns suggested that these membranes had amor- phous structure at room temperature. The membranes doped with bistrifluoromethanesulfonimide lithium salt（LiTFSI）and plasticized with succinonitrile（SN）displayed high lithium ionic conductivity at 80℃ （6.4 × 10^-5 ~ 5.30 × 10^-4 S/cm）.