摘要
通过叠氮化超支化聚苯乙烯(HBPS-N3)与端炔基聚乙二醇单甲醚(ay-PEO)的点击反应,合成了以超支化聚苯乙烯(HBPS)为核、不同分子量的聚氧化乙烯(PEO)为臂的多臂星形聚合物(HBPS-PEO),并利用ATR-FTIR,1H-NMR,GPC对合成的星形聚合物的结构进行了表征.将该种星形聚合物与双三氟甲基磺酰亚胺锂(LiTFSI)进行复合,制备了星形聚合物为基体的聚合物电解质,通过交流阻抗技术和DSC对该聚合物电解质的离子导电性能及热性能进行了研究.结果表明,星形结构可以在一定程度上抑制结晶的形成,这种新型的星形聚合物电解质的室温电导率明显高于相应的线形聚合物电解质,当n(EO)/n(Li)=40,PEO臂的分子量为1000时,该星形聚合物电解质的离子电导率最高,30℃时为6.7×10-5Scm-1,40℃时可以达到1.2×10-4Scm-1;TGA结果表明,制备的星形聚合物的初始分解温度(Tonset)都高于360℃,具有良好的热稳定性.
In order to obtain polymer electrolytes with high ionic conductivity at room temperature,multi-arm star polymers(HBPS-PEO) containing polyoxyethylene arms of different molecular weights(PEO750,PEO1000 and PEO1900) were successfully synthesized by click chemistry of hyperbranched polystyrene with azide groups(HBPS-N3) and polyoxyethylene with an alkynyl group(ay-PEO).The structures of the obtained star polymers were characterized by ATR-FTIR,1H-NMR,GPC,respectively.Ionic conductivities of polymer electrolytes composed of HBPS-PEO and lithium trifluoromethane-sulfonimide(LiTFSI) were investigated via electrochemical impedance spectroscopy.The influences of the arm length of the prepared star polymer,the content of lithium salt in polymer electrolyte and the structure of the polymer matrix on ionic conductivity were also studied.The results showed that star polymer electrolyte with arms of PEO1000 exhibited the highest ionic conductivity,while star polymer electrolyte with arms of PEO1900 had the lowest ionic conductivity,indicating the star polymer with shorter PEO arms possessing lower crystallinity was benefit for the transport of ions.The content of lithium salt also affected the ionic conductivity.The result suggested that ionic conductivity first increased and then decreased gradually with the change of the content of lithium salt.The maximum was achieved when n(EO)/n(Li)=40.Besides,DSC results showed that the star-shaped structure of the polymer could inhibit the formation of crystals.Lower degree of crystallinity of star polymer and star polymer electrolyte than corresponding linear PEO was observed,and higher ionic conductivity at low temperatures was found for electrolyte based on star polymer than that of corresponding linear PEO electrolyte.The conductivity of the star polymer electrolyte was 6.7×10-5 Scm-1 at 30 ℃,and could reach 1.2×10-4 Scm-1 at 40 ℃.TGA results showed that all of the prepared star polymers exhibited good thermal stability with Tonset above 360 ℃.It is concluded that star-bran
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2013年第8期1064-1071,共8页
Acta Polymerica Sinica
基金
国家自然科学基金(基金号51073170,50703044)资助项目
