Next Article in Journal
Preparation and Characterization of Antibacterial Cellulose/Chitosan Nanofiltration Membranes
Next Article in Special Issue
Unfolding Kinetics of a Wormlike Chain under Elongational Flow
Previous Article in Journal
Reaction-Multi Diffusion Model for Nutrient Release and Autocatalytic Degradation of PLA-Coated Controlled-Release Fertilizer
Previous Article in Special Issue
Buckling a Semiflexible Polymer Chain under Compression
Article Menu
Issue 4 (April) cover image

Export Article

Open AccessArticle
Polymers 2017, 9(4), 115; doi:10.3390/polym9040115

Carbon Nanotube Length Governs the Viscoelasticity and Permeability of Buckypaper

1
Department of Mechanical Engineering, University of Connecticut, Storrs, CT 06269, USA
2
RISE Bioscience and Materials, Box 5401, 402 29 Göteborg, Sweden
3
School of Energy and Resources, UCL Australia, University College London, Adelaide SA 5000, Australia
4
Polymer Physics, Department of Materials, ETH Zürich, CH-8093 Zurich, Switzerland
5
Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA
*
Authors to whom correspondence should be addressed.
Academic Editor: Patrick Ilg
Received: 9 February 2017 / Revised: 17 March 2017 / Accepted: 17 March 2017 / Published: 23 March 2017
(This article belongs to the Special Issue Semiflexible Polymers)
View Full-Text   |   Download PDF [5378 KB, uploaded 23 March 2017]   |  

Abstract

The effects of carbon nanotube (CNT) length on the viscoelasticity and permeability of buckypaper, composed of (5,5) single-walled CNTs (SWCNTs), are systematically explored through large-scale coarse-grained molecular dynamics simulations. The SWCNT length is found to have a pronounced impact on the structure of buckypapers. When the SWCNTs are short, they are found to form short bundles and to be tightly packed, exhibit high density and small pores, while long SWCNTs are entangled together at a low density accompanied by large pores. These structure variations contribute to distinct performances in the viscoelasticity of buckypapers. The energy dissipation for buckypapers with long SWCNTs under cyclic shear loading is dominated by the attachment and detachment between SWCNTs through a zipping-unzipping mechanism. Thus, the viscoelastic characteristics of buckypapers, such as storage and loss moduli, demonstrate frequency- and temperature-independent behaviors. In contrast, the sliding-friction mechanism controls the energy dissipation between short SWCNTs when the buckypaper is under loading and unloading processes. Friction between short SWCNTs monotonically increases with rising length of SWCNTs and temperature. Therefore, the tan δ , defined as the ratio of the loss modulus over the storage modulus, of buckypaper with short SWCNTs also increases with the increment of temperature or SWCNT length, before the SWCNTs are entangled together. The permeability of buckypapers is further investigated by studying the diffusion of structureless particles within buckypapers, denoted by the obstruction factor ( β ). It is found to be linearly dependent on the volume fraction of SWCNTs, signifying a mass-dominated permeability, regardless of the structure variations induced by different SWCNT lengths. The present study provides a comprehensive picture of the structure-property relationship for buckypapers composed of SWCNTs. The methodology could be used for designing multifunctional buckypaper-based devices. View Full-Text
Keywords: buckypaper; carbon nanotube; viscoelasticity; permeability; molecular dynamics buckypaper; carbon nanotube; viscoelasticity; permeability; molecular dynamics
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Shen, Z.; Röding, M.; Kröger, M.; Li, Y. Carbon Nanotube Length Governs the Viscoelasticity and Permeability of Buckypaper. Polymers 2017, 9, 115.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Polymers EISSN 2073-4360 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top