Featured Research

from universities, journals, and other organizations

Fossilized Liquid Assembly: Nanomaterials Research Tool

Date:
October 18, 2006
Source:
National Institute of Standards and Technology
Summary:
From a butterfly's iridescent wing to a gecko's sticky foot, nature derives extraordinary properties from ordinary materials like wax and keratin. Its secret is hierarchical topology -- macroscale structures assembled from microscale components of varying sizes. Borrowing a page from nature's playbook, researchers at NIST have developed a novel platform for the self-assembly of experimental hierarchical surfaces in a fluid. Their work offers diverse industries a new way to generate and measure self-assembly at the nanoscale.

Optical microscope image (lower plane) shows spheres at mutiple size scales self-arranging in complex "super-assemblies" in NIST's hierarchical topology modeling system. Atomic-force microscopy (detail) shows the textured surface formed by the spheres.
Credit: NIST

From a butterfly's iridescent wing to a gecko's sticky foot, nature derives extraordinary properties from ordinary materials like wax and keratin. Its secret is hierarchical topology: macroscale structures assembled from microscale components of varying sizes. Borrowing a page from nature's playbook, researchers at the National Institute of Standards and Technology (NIST) have developed a novel platform for the self-assembly of experimental hierarchical surfaces in a fluid. Their work offers diverse industries a new way to generate and measure self-assembly at the nano-scale.

A butterfly's wings shimmer because light plays upon tiny rows of scales, like tiles on a Spanish roof. The gecko sticks to surfaces because its feet are patterned with microscopic hairs, each hair tipped with hundreds of even tinier projections. Beads of water roll off the lotus's leaf because its surface is streaked with microscopic peaks, each with a finer structure, that makes the surface "super hydrophobic." These enhanced properties--other possibilities include super adhesion and low friction--have attracted the attention of design engineers for applications from bioengineered tissues to photonic crystals to submarines that slice through water with minimal drag.

Creating these topologically complex, self-assembled surfaces for study has been a challenge. If the components are mixed on a surface, that substrate affects how they assemble; if mixed in a solvent and dried, the drying process similarly distorts the results. In a recent paper*, the NIST team detailed a much simpler and faster system they dubbed "fossilized liquid assembly" to create experimental models of hierarchical topologies in which the components are allowed to mix and assemble freely in a fluid, and then quickly "frozen" in place for study. The key is the use of solutions of water and a special monomer that polymerizes--links together--when exposed to ultraviolet light. Like an oil-water mixture, the fluid forms liquid interfaces that can be manipulated to create a desired hierarchical structure and then suddenly solidified with a burst of UV light.

Lead researcher and physicist Alamgir Karim estimates that it takes about five minutes to make a sample of self-assembling particles using NIST's approach. Other methods, he notes, not only are more complicated and costly, but also do not allow the structures to form as freely. With the new technique, engineers also will be able to build complex dynamic structures and freeze them into solid form, studying self-assembly under the microscope. "How do you take a snapshot of shampoo in action?" asks physicist Jason Benkoski, first author of the paper. "We can now directly observe these small, mobile, delicate structures."

The researchers also are using the new platform to better understand the fundamental physics behind the formation of hierarchical topology, studying, for example how different forces dominate at different scales of length. Looking ahead, the NIST team plans to build on this study, expanding the technology as a 3D imaging platform.

The work was supported by NIST and a National Research Council Fellowship.

* J.J. Benkoski, H. Hu, and A. Karim. Generation of hierarchical topologies from photocrosslinkable, particle-stabilized emulsions. Macromolecular Rapid Communications. Aug. 2, 2006


Story Source:

The above story is based on materials provided by National Institute of Standards and Technology. Note: Materials may be edited for content and length.


Cite This Page:

National Institute of Standards and Technology. "Fossilized Liquid Assembly: Nanomaterials Research Tool." ScienceDaily. ScienceDaily, 18 October 2006. <www.sciencedaily.com/releases/2006/10/061012184208.htm>.
National Institute of Standards and Technology. (2006, October 18). Fossilized Liquid Assembly: Nanomaterials Research Tool. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2006/10/061012184208.htm
National Institute of Standards and Technology. "Fossilized Liquid Assembly: Nanomaterials Research Tool." ScienceDaily. www.sciencedaily.com/releases/2006/10/061012184208.htm (accessed September 17, 2014).

Share This



More Matter & Energy News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Space Race Pits Bezos Vs Musk

Space Race Pits Bezos Vs Musk

Reuters - Business Video Online (Sep. 16, 2014) — Amazon CEO Jeff Bezos' startup will team up with Boeing and Lockheed to develop rocket engines as Elon Musk races to have his rockets certified. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
MIT's Robot Cheetah Unleashed — Can Now Run, Jump Freely

MIT's Robot Cheetah Unleashed — Can Now Run, Jump Freely

Newsy (Sep. 16, 2014) — MIT developed a robot modeled after a cheetah. It can run up to speeds of 10 mph, though researchers estimate it will eventually reach 30 mph. Video provided by Newsy
Powered by NewsLook.com
Manufacturer Prints 3-D Car In Record Time

Manufacturer Prints 3-D Car In Record Time

Newsy (Sep. 15, 2014) — Automobile manufacturer Local Motors created a drivable electric car using a 3-D printer. Printing the body only took 44 hours. Video provided by Newsy
Powered by NewsLook.com
Refurbished New York Subway Tunnel Unveiled After Sandy Damage

Refurbished New York Subway Tunnel Unveiled After Sandy Damage

Reuters - US Online Video (Sep. 15, 2014) — New York officials unveil subway tunnels that were refurbished after Superstorm Sandy. Nathan Frandino reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

      Technology News



      Save/Print:
      Share:  

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile iPhone Android Web
      Follow Facebook Twitter Google+
      Subscribe RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins