Navigation Links
Fitter frames: Nanotubes boost structural integrity of composites
Date:3/26/2009

Troy, N.Y. A new research discovery at Rensselaer Polytechnic Institute could lead to tougher, more durable composite frames for aircraft, watercraft, and automobiles.

Epoxy composites are increasingly being incorporated into the design of new jets, planes, and other vehicles. Composite material frames are extremely lightweight, which lowers the overall weight of the vehicle and boosts fuel efficiency. The downside is that epoxy composites can be brittle, which is detrimental to its structural integrity.

Professor Nikhil Koratkar, of Rensselaer's Department of Mechanical, Aerospace, and Nuclear Engineering, has demonstrated that incorporating chemically treated carbon nanotubes into an epoxy composite can significantly improve the overall toughness, fatigue resistance, and durability of a composite frame.

When subjected to repetitive stress, a composite frame infused with treated nanotubes exhibited a five-fold reduction in crack growth rate as compared to a frame infused with untreated nanotubes, and a 20-fold reduction when compared to a composite frame made without nanotubes.

This newfound toughness and crack resistance is due to the treated nanotubes, which enhance the molecular mobility of the epoxy at the interface where the two materials touch. When stressed, this enhanced mobility enables the epoxy to craze or result in the formation of a network of pillar-like fibers that bridge together both sides of the crack and slow its growth.

"This crazing behavior, and the bridging fibers it produces, dramatically slows the growth rate of a crack," Koratkar said. "In order for the crack to grow, those fibers have to first stretch, deform plastically, and then break. It takes a lot of energy to stretch and break those fibers, energy that would have otherwise gone toward enlarging the crack."

Results of the study were published this week in the journal Small.

Epoxy composites infused with carbon nanotubes are known to be more resistant to cracks than pure epoxy composites, as the nanotubes stitch, or bridge, the two sides of the crack together. Infusing an epoxy with carbon nanotubes that have been functionalized, or treated, with the chemical group amidoamine, however, results in a completely different bridging phenomenon.

At the interface of the functionalized nanotubes and the epoxy, the epoxy starts to craze, which is a highly unusual behavior for this particular type of composite, Koratkar said. The epoxy deforms, becomes more fluid, and creates connective fibers up to 10 microns in length and with a diameter between 100 nanometers and 1,000 nanometers.

"We didn't expect this at all. Crazing is common in certain types of thermoplastic polymers, but very unusual in the type of epoxy composite we used," Koratkar said. "In addition to improved fatigue resistance and toughness, the treated nanotubes also enhanced the stiffness, hardness, and strength of the epoxy composite, which is very important for structural applications."

Koratkar said the aircraft, boat, and automobile industries are increasingly looking to composites as a building material to make vehicle frames and components lighter. His research group plans to further investigate crazing behavior in epoxy composites, in order to better understand why the chemical treatment of nanotubes initiates crazing.


'/>"/>

Contact: Michael Mullaney
mullam@rpi.edu
518-276-6161
Rensselaer Polytechnic Institute
Source:Eurekalert  

Related biology technology :

1. UB engineers prove that carbon nanotubes are superior to metals for electronics
2. Nanotubes find niche in electric switches
3. Spinning carbon nanotubes spawns new wireless applications
4. Semiconducting nanotubes produced in quantity at Duke
5. Sigma-Aldrich Signs Agreement With SouthWest NanoTechnologies to Distribute SWeNT(R) Single-Wall Carbon Nanotubes
6. Paperwork: Buckypapers clarify electrical, optical behavior of nanotubes
7. Dry adhesive based on carbon nanotubes gets stronger, with directional gripping ability
8. Tsunami invisibility cloak, dark energy v. the void, sorting nanotubes with light, and more
9. Water purification down the nanotubes
10. True properties of carbon nanotubes measured
11. LLNL researchers peer into water in carbon nanotubes
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Fitter frames: Nanotubes boost structural integrity of composites
(Date:10/12/2017)... ... 12, 2017 , ... DuPont Pioneer and recently formed CasZyme, ... into a multiyear collaboration to identify and characterize novel CRISPR-Cas nucleases. The goal ... editing across all applications. , Under the terms of the agreement, Pioneer will ...
(Date:10/11/2017)... ... October 11, 2017 , ... At its national board ... Suneel I. Sheikh, the co-founder, CEO and chief research scientist of Minnesota-based Advanced ... for membership in ARCS Alumni Hall of Fame . ASTER Labs is ...
(Date:10/11/2017)... , Oct. 11, 2017  VMS BioMarketing, a leading provider ... nationwide oncology Clinical Nurse Educator (CNE) network, which will launch ... for communication among health care professionals to enhance the patient ... office staff, and other health care professionals to help women ... cancer. ...
(Date:10/10/2017)... (PRWEB) , ... October 10, 2017 , ... San Diego-based ... of its corporate rebranding initiative announced today. The bold new look is part ... as the company moves into a significant growth period. , It will also expand ...
Breaking Biology Technology:
(Date:4/17/2017)... NXT-ID, Inc. (NASDAQ: NXTD ) ("NXT-ID" or the ... Annual Report on Form 10-K on Thursday April 13, 2017 with ... ... Relations section of the Company,s website at http://www.nxt-id.com  under "SEC ... . 2016 Year Highlights: Acquisition ...
(Date:4/11/2017)... Fla. , April 11, 2017 ... and secure authentication solutions, today announced that it ... Intelligence Advanced Research Projects Activity (IARPA) to develop ... Thor program. "Innovation has been a ... IARPA,s Thor program will allow us to innovate ...
(Date:4/11/2017)... -- NXT-ID, Inc. (NASDAQ:   NXTD ) ("NXT-ID" ... of independent Directors Mr. Robin D. Richards and ... furthering the company,s corporate governance and expertise. ... Gino Pereira , Chief Executive Officer ... guidance and benefiting from their considerable expertise as we move ...
Breaking Biology News(10 mins):