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

Zhen-Yu Wang; Xiao-Kong Liu

doi:10.1007/s10118-024-3199-0

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

RESEARCH ARTICLE | Updated：2024-09-23

- Polymer-to-Monomers Chemically Recyclable Poly(imide-imine) Plastics with Extreme-Condition Resistance and Flame Retardancy
- Chinese Journal of Polymer Science Vol. 42, Issue 10, Pages: 1525-1535(2024)
- Affiliations：
  
  State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China
- Author bio：
  
  xiaokongliu@jlu.edu.cn
- Funds：
- DOI：10.1007/s10118-024-3199-0
  CLC： M
- Received：01 May 2024，
  
  Revised：2024-06-14，
  
  Accepted：21 June 2024，
  
  Online First：02 September 2024，
  
  Published：01 October 2024
- Accepted：
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Wang, Z. Y.; Liu, X. K. Polymer-to-monomers chemically recyclable poly(imide-imine) plastics with extreme-condition resistance and flame retardancy. Chinese J. Polym. Sci. 2024, 42, 1525–1535

Zhen-Yu Wang, Xiao-Kong Liu. Polymer-to-Monomers Chemically Recyclable Poly(imide-imine) Plastics with Extreme-Condition Resistance and Flame Retardancy[J]. Chinese Journal of Polymer Science, 2024, 42(10): 1525-1535.
Wang, Z. Y.; Liu, X. K. Polymer-to-monomers chemically recyclable poly(imide-imine) plastics with extreme-condition resistance and flame retardancy. Chinese J. Polym. Sci. 2024, 42, 1525–1535 DOI： 10.1007/s10118-024-3199-0.

Zhen-Yu Wang, Xiao-Kong Liu. Polymer-to-Monomers Chemically Recyclable Poly(imide-imine) Plastics with Extreme-Condition Resistance and Flame Retardancy[J]. Chinese Journal of Polymer Science, 2024, 42(10): 1525-1535. DOI： 10.1007/s10118-024-3199-0.

摘要

A dynamic covalent poly(imide-imine) polymer with excellent flame retardancy is reported

exhibiting comparable properties to the commercial polyimides

including exceptional mechanical properties

high thermal stability

and outstanding chemical resistance. The plastic can be depolymerized and converted back into the initial pure monomers that can be used to regenerate new-generation plastics.

Abstract

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 °C. 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

Keywords

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