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Fracture Behavior of a 2D Imine-Based Polymer
Bowen Zhang1,2, Xiaohui Liu3, David Bodesheim4
1Fraunhofer Institute for Ceramic Technologies and System (IKTS), Maria-Reiche-Straße 2, 01109, Dresden, Germany.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|September 12, 2024
Summary
This study reveals how 2D polyimine films fracture, showing side cracks toughen the material. Understanding these fracture kinetics is key for designing durable 2D nanomaterials.
Area of Science:
- Materials Science
- Nanotechnology
- Polymer Science
Background:
- Two-dimensional (2D) polymers are promising nanomaterials with exceptional properties.
- Limited understanding of their fracture behavior hinders practical applications and durability.
Purpose of the Study:
- To investigate the fracture kinetics and failure mechanisms of a 2D polyimine film.
- To elucidate the intrinsic mechanical properties and fracture behavior of imine-linked polymers.
Main Methods:
- In situ tensile testing within a transmission electron microscope (TEM).
- Digital image correlation (DIC) analysis for strain evolution.
- Density functional-based tight binding (DFTB) calculations.
Main Results:
- Achieved an elastic strain of ≈6.5% and an elastic modulus of (8.6 ± 2.5) GPa for 2D polyimine films.
- Observed side crack initiation and development that toughen the film.
- Confirmed both transgranular and intergranular fracture patterns with a preferred cleavage orientation.
Conclusions:
- Developed a comprehensive understanding of 2D polyimine fracture behavior.
- Insights provided for the rational design of robust 2D polymers.
- Demonstrated the toughening effect of side cracking in 2D polymer films.
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