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Entanglements and Fracture in Polymers.
Taewon Kang1, Jinyue Dai1, Yan Huang1
1Department of Mechanical Engineering, Northwestern University, Evanston, Illinois 60208-0001, United States.
Chemical Reviews
|October 3, 2025
Summary
Polymer chain entanglements significantly influence material properties, affecting elasticity, viscoelasticity, and fracture behavior. Understanding these relationships aids in designing durable polymers and inferring structure from fracture data.
Area of Science:
- Polymer Science
- Materials Science
- Mechanics of Materials
Background:
- Polymer chains entangle, forming a microstructure that dictates material properties.
- Entangled chains cannot pass but transmit tension, influencing elastic, viscoelastic, and fracture behaviors.
Purpose of the Study:
- To review recent advancements in understanding the link between polymer entanglements and fracture.
- To summarize fracture properties across various polymer systems and discuss the role of entanglements.
Main Methods:
- Literature review of recent research on polymer entanglements and fracture.
- Synthesis of data on fracture properties (toughness, strength, etc.) in different polymer types.
Main Results:
- Entanglements critically affect polymer fracture properties, including toughness, strength, and fatigue limits.
- The influence of entanglements varies across polymer systems like gels, elastomers, and plastics.
Conclusions:
- A comprehensive understanding of entanglement-fracture relationships is key for designing mechanically robust polymers.
- Fracture properties can provide insights into the underlying polymer microstructure and entanglement network.
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