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Fabrication of Large-area Free-standing Ultrathin Polymer Films
Published on: June 3, 2015
High strength films from oriented, hydrogen-bonded "graphamid" 2D polymer molecular ensembles
Emil Sandoz-Rosado1, Todd D Beaudet1, Jan W Andzelm1
1U.S. Army Research Laboratory, Aberdeen Proving Ground, MD, 21005, United States.
Scientific Reports
|March 1, 2018
Summary
Researchers developed graphamid, a novel 2D polymer inspired by Kevlar. This material exhibits superior strength and toughness due to strong hydrogen bonds, offering potential for advanced lightweight films.
Area of Science:
- Materials Science
- Polymer Chemistry
- Nanotechnology
Background:
- Poly(p-phenylene terephthalamide), known as Kevlar, is a high-performance linear polymer.
- Kevlar's exceptional properties include strength, stiffness, and environmental resistance.
- Traditional 2D materials like graphene possess weak intermolecular interactions.
Purpose of the Study:
- To introduce a new two-dimensional (2D) polymer, "graphamid", with enhanced mechanical properties.
- To compare graphamid's mechanical performance with traditional 2D materials.
- To explore the potential of graphamid for creating high-performance polymer films.
Main Methods:
- Atomistic calculations to analyze graphamid's structure and bonding.
- Molecular and micromechanical calculations to predict mechanical properties.
- Comparative analysis with existing 2D materials like graphene.
Main Results:
- Graphamid features covalently-bonded sheets interconnected by strong intermolecular hydrogen bonds.
- Predicted mechanical properties include high strength (6-8 GPa), stiffness, and toughness.
- Graphamid films demonstrate significantly higher mechanical performance compared to graphene.
Conclusions:
- Strong intermolecular hydrogen bonds are key to graphamid's superior mechanical advantages.
- Graphamid represents a transformative material for scalable, lightweight, high-performance polymer films.
- This 2D polymer offers unprecedented mechanical performance for advanced applications.
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