基于金属配位作用制备高性能聚酰亚胺  

Preparation of High Performance Polyimide Based on Metal Coordination Bond

作　　者：杨晨 李琇廷 董杰[1] 赵昕[1] 龚静华[1] 张清华[1] Chen Yang;Xiu-ting Li;Jie Dong;Xin Zhao;Jing-hua Gong;Qing-hua Zhang(State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,Donghua University,Shanghai 201620)

机构地区：[1]东华大学纤维材料改性国家重点实验室,上海201620

出　　处：《高分子学报》2022年第6期663-672,共10页Acta Polymerica Sinica

基　　金：盛虹·应急保障与公共安全用纤维材料及制品科研攻关项目(项目号2021-fx020204)资助.

摘　　要：通过分子结构设计合成了含金属配位交联网络的可溶性聚酰亚胺,由于Cu^(2+)与聚酰亚胺侧链羧基之间的配位交联作用限制了聚酰亚胺分子链的运动,使材料的T_(g)得到显著提升.同时,由于Cu^(2+)具有非球面对称的电子云结构,导致Cu^(2+)在与有机配体配位时存在额外的晶体场稳定能(CFSE)以及较强Jahn-Teller效应(JTE),使配位键能够在有机溶剂中稳定存在,极大地提高了薄膜的抗溶剂性能,制备的聚酰亚胺膜在DMF、DMAc等强极性溶剂中室温下浸泡48 h后质量残留率仍可高达80%.此外,在聚酰亚胺分子结构中引入金属离子配位作用使其力学性能明显提升,拉伸强度从93 MPa提高到128 MPa.研究结果为开发高性能可溶性聚酰亚胺材料提供新途径.Soluble polyimide containing metal coordination crosslinking network was synthesized through molecular structure design.Based on the coordination crosslinking between Cu^(2+)and the lateral carboxyl group of polyimide,the mobility of polyimide chain in solid state was limited and the Tg of the material was significantly improved.The Tg of the original polyimide is about 320℃,while the T_(g) of coordination crosslinked polyimide PI-Cu50% can reach about 362℃.After coordination with Cu^(2+),the initial“push-pull”electronic mode of polyimide is destroyed,the existing state of electrons in the main chain was changed,and the fluorescence intensity of polyimide was weakened.Meanwhile,Cu^(2+)has an aspherical symmetrical electron cloud structure,resulting in additional crystal field stability energy(CFSE)and strong Jahn teller effect(JTE)when Cu^(2+)coordinates with organic ligands,so that the coordination bond can exist stably in organic solvents,After the introduction of copper chloride,crosslinking network based on Cu^(2+) coordination was formed in the molecular structure of polyimide which greatly improves the solvent corrosion resistance of the films.The original polyimide film can be completely dissolved after soaking in strong polar solvents such as N,N-dimethylformamide(DMF),N-methylacetamide(DMAc)and N-methylpyrrolidone(NMP)and standing at room temperature for two days,while the mass residue rate of the coordination crosslinked polyimide film PI-Cu50% can still be as high as 80% after soaking in strong polar solvents such as DMF and DMAc at room temperature for 48 h.Due to the decarboxylation crosslinking reaction of carboxyl group at about 400℃,the T_(d5) of polyimide containing carboxyl group is low,and the thermal stability of carboxyl group was significantly improved when coordinated with Cu^(2+),so the T_(d5) of polyimide was improved.Moreover,the introduction of metal ion coordination into the polyimide molecular structure also improved its mechanical properties,and the tensile strength of film

关 键 词：聚酰亚胺 金属-配体配位 交联聚合物 抗溶剂腐蚀性 机械性能 

分 类 号：TQ317[化学工程—高聚物工业]