Polymer-to-Monomers Chemically Recyclable Poly(imide-imine)Plastics with Extreme-Condition Resistance and Flame Retardancy  

作　　者：Zhen-Yu Wang Xiao-Kong Liu 

机构地区：[1]State Key Laboratory of Supramolecular Structure and Materials,College of Chemistry,Jilin University,Changchun,130012,China

出　　处：《Chinese Journal of Polymer Science》2024年第10期1525-1535,I0012,共12页高分子科学（英文版）

基　　金：supported by Natural Science Foundation of Jilin Province(No.***202302003);the National Natural Science Foundation of China(No.22275069);National Key R&D Program of China(No.2023YFA1008804)。

摘　　要：Polyimides are a family of high-tech plastics that have irreplaceable applications in the fields of aerospace,defense,and opto-electronics,but polyimides are difficult to be reprocessed and recycled at the end of their service life,resulting in a significant waste of resources.Hence,it is of great significance to develop recyclable polyimides with comparable properties to the commercial products.Herein,we report a novel polymer-to-monomers chemically recyclable poly(imide-imine)(PtM-CR-PII)plastic,synthesized by cross-linking the amine-terminated aromatic bisimide monomer and the hexa-vanillin terminated cyclophosphazene monomer via dynamic imine bonds.The PtM-CR-PII plastic exhibits comparable mechanical and thermal properties as well as chemical stability to the commercial polyimides.The PtM-CR-PII plastic possesses a high Young’s modulus of≈3.2 GPa and a tensile strength as high as≈108 MPa,which also exhibits high thermal stability with a glass transition temperature of≈220℃.Moreover,the PtM-CR-PII plastic exhibits outstanding waterproofness,acid/alkali-resistance,and solvent-resistance,its appearance and mechanical properties can be well maintained after long-term soaking in water,highly concentrated acid and base,and various organic solvents.Furthermore,the cyclophosphazene moieties endow the PtM-CR-PII plastic with excellent flame retardancy.The PtM-CR-PII plastic exhibits the highest UL-94 flame-retarding rating of V-0 and a limiting oxygen index(LOI)value of 45.5%.Importantly,the PtM-CR-PII plastic can be depolymerized in an organic solvents-acid mixture medium at room temperature,allowing easy separation and recovery of both monomers in high purity.The recovered pure monomers can be used to regenerate new PtM-CR-PII plastics,enabling sustainable polymer-monomers-polymer circulation.

关 键 词：Chemical recyclability Polyimides POLYIMINES Dynamic imine bonds Mechanical properties Chemical stability 

分 类 号：TQ323.7[化学工程—合成树脂塑料工业]