Mechanical Properties of Amide Functionalized CNT/NBR at Different Temperatures: A Molecular Dynamics Study
Longcheng Ji1, Lijia Chen1, Li Lin1
1School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, China.
Polymers
|April 12, 2022
Summary
This study simulated carbon nanotube/rubber composites, finding amide-functionalized nanotubes significantly improve mechanical properties by 5-26% due to enhanced bonding and restricted movement at various temperatures.
Area of Science:
- Materials Science
- Polymer Science
- Computational Chemistry
Background:
- Carbon nanotubes (CNTs) are promising fillers for polymer composites.
- Nitrile butadiene rubber (NBR) is a widely used elastomer.
- Understanding filler-matrix interactions is crucial for composite performance.
Purpose of the Study:
- To investigate the mechanical properties of pure carbon nanotube (PCNT)/NBR and amide-functionalized carbon nanotube (CONH2-CNT)/NBR composites.
- To analyze the effects of temperature on composite properties, free volume, and molecular dynamics.
- To elucidate the interfacial enhancement mechanism at an atomic level.
Main Methods:
- Molecular dynamics (MDs) simulations were employed.
- Simulations were conducted at various temperatures.
- Analysis included mechanical properties, fractional free volume (FFV), mean squared displacement (MSD), dipole autocorrelation function, and hydrogen bonding.
Main Results:
- Amide-functionalized CNTs formed stronger interfacial binding energies with NBR due to hydrogen bonds.
- FFV and MSD were restricted in the composites, particularly with functionalized CNTs.
- Mechanical properties of the composites were enhanced by 5.02-25.93%.
Conclusions:
- Hydrogen bonding significantly improves the interface interaction between CONH2-CNTs and the NBR matrix.
- Temperature influences the molecular dynamics and mechanical response of the composites.
- Functionalized CNTs offer a viable strategy for enhancing the performance of NBR-based composites.
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