Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > From Nature's nanolaboratory

Here are Nature's own mini-mini reinforcement rods. Fibrils are extracted from cells in pine timber. They have a diameter of 50 millionths of a millimetre (nanometres).
Here are Nature's own mini-mini reinforcement rods. Fibrils are extracted from cells in pine timber. They have a diameter of 50 millionths of a millimetre (nanometres).

Abstract:
Their day job is to keep trees upright. But now the forest's tiniest building blocks are on their way into fancy products for the future.

From Nature's nanolaboratory

Norway | Posted on December 12th, 2007

Imagine a packaging material that kills bacteria and keeps food longer in good condition. Or a disposable duvet cover that keeps infection away from you when you lie in a hospital bed.

Scientists in Trondheim believe that a lot of exciting new products can be created if we can manage to make use of some of Nature's tiniest construction materials. They are called "fibrils"; a word you have probably never heard of. But in fact, there are millions of them in the paper you have in your hands just now.


A wonder of Nature

Midsummer night, 2005: a steady stream of print journalists and TV teams arrive on the SINTEF/NTNU campus, where they are greeted by proud metallurgists in lab-coats and safety helmets. They have achieved large-scale production of carbon nanotubes, a material with a tensile strength ten times as high as the strongest steel, but weighing only one tenth as much.

This super-material was created in a 30 000 degree plasma arc.

Little do the reporters know of what is going on in the building next door, which belong to the Paper and Fibre Institute (PFI). There, and in the adjacent laboratories, a handful of busy people from PFI, SINTEF and NTNU are working on fibrils - nanocomponents that Nature creates all by itself, with the help of sunlight, air and water.

Fibrils form continuously in all growing trees. In terms of strength, they cannot be compared with carbon nanotubes, but they are strong enough for SINTEF's Bjørn Steinar Tanem to regard them as potential reinforcement materials in plastics, as he sits and admires them in the electron microscope.


Reinforcement rods of sugar

Fibrils are Nature's own mini-mini-reinforcement rods. They consist of long sugar molecules (cellulose), arranged in bundles These bundles make up the wall of the drinking straw-like wood cells that tree-trunks consist of.

It is the tough strength of the fibrils that keeps the giants of the forest swaying but upright in the strongest gusts of wind. The material has evolved in one of the world's biggest nano-laboratories: the forest.
"And Nature has taken millions of years to perfect the process," says Tanem.

In paper mills, the cells are beaten and squashed flat, to re-appear in the form of paper fibres; or by boiling them, they can be turned into cellulose.

It is already quite possible to separate the fibrils from wood cells, and to extract bundles of molecules that are measured in nanometres; i.e. millionths of a millimetre. But the process is expensive.

Now scientists in many laboratories in the western world, including Trondheim, are trying to make the process more energy- and cost-efficient. But this is no easy job, according to Kristin Syverud of the Paper and Fibre Institute.

"It has taken a lot of energy to build up these wood cells in Nature, and then we come along and want to use as little energy as possible to tear them apart again."


Valuable strength

PFI has been working for three years on a basic research project on fibrils, with financial support from the Research Council of Norway and in close cooperation with scientists from SINTEF and NTNU. According to Syverud, there is no lack of scientific challenges, but she believes that the topic is worth a bit of effort, since fibrils possess many qualities that fascinate the scientists, one of them being their strength.

Fibrils are long in comparison with their diameter, which makes them good at absorbing forces. According to SINTEF's Tanem, they are therefore very suitable as reinforcements for plastics. He predicts, for example, that they could enable plastics to be used in automotive components.

The Trondheim scientists wish to use fibrils in biopolymers; materials produced from natural products such as maize starch. The aim is to develop composite structures whose life cycle will have the least possible impact on the environment.

"Fibrils can give biopolymers new, improved properties which, in conjunction with good design, could form the basis of thinner-walled moulded products, for example, thus reducing the amount of raw material needed," says Tanem.

However, the first necessity is for more research. For one thing, getting the fibrils into plastic is no simple task. But according to Tanem, the group has already made progress in this aspect.

As a parallel activity, PhD student Martin Andersen at NTNU and SINTEF's Per Martin Stenstad have been manipulating the surface of the fibrils, producing the alterations that are needed to make them "comfortable" within the plastic matrix.

PFI's Kristin Syverud is particularly taken by the results of a quite different application.


Combating bacteria

The surface of fibrils makes it easy to link them to other active substances, and here too, surface scientists Andersen and Stenstad have been using their expertise. Stenstad, in fact, has worked on similar projects with the famous "Ugelstad microspheres". For this "fibrils with attachments" variant, the Trondheim scientists selected a chemical that kills micro-organisms, which they have managed to make stick tightly to the fibrils.

"This is important, for substances of this sort must not leach out and end up in the wrong place," says Syverud.

She explains that these results have spawned exciting product concepts within the project group, including the idea of using fibrils to make bactericidal food wrappings, disposable duvet covers and water filters.

The list of potential applications for fibrils is long, ranging over several branches of industry (see fact-box). However, the scientists still have a good deal to work on before fibrils are ready to hit the shelves.


Processing fever

"Controlling the size distribution of the fibrils once they have been separated out is one of the challenges that still make us tear our hair," says Syverud, who has been leading the project together with Per Stenius, an adjunct professor at NTNU.

Two different mechanical techniques are in use today to extract the fibrils from the wood cells: a mill, and a nozzle that produces a large pressure drop. Both are energy-intensive. However, according to Syverud,there is already know-how, for example at PFI's Swedish owners, that will significantly reduce energy consumption. She is also quite certain that this research will lead to commercial products.

"However, which of all the potential areas of application will take off is something we don't know yet. And I am sure that not all of our ideas will end up as products."

The western world's cellulose industry is the driving force behind fibril research. The industrialised world has realised that it is difficult to compete on price for traditional cellulose, and is looking around for applications for processed cellulose. Kristin Syverud believes that the global focus on the environment will contribute to the demand for fibrils.

"They are a renewable resource that is being created by Nature around us every day. And they are certainly cheap," she says.

As for me, I will be looking at trees with a bit more respect next time I am walking in the woods.



Fact-box: Many areas of application

Extremely strong but transparent plastic packaging materials
Stronger newsprint and magazine paper with good print characteristics
Stable emulsions - suspensions of fat-based substances in water, or of water in fat
Reduced turbulence in pipeline transportation of oil
Thickening agents for everything from food to cosmetics
New types of membranes

####

About SINTEF
The SINTEF Group is the largest independent research organisation in Scandinavia. Every year, SINTEF supports the development of 2000 or so Norwegian and overseas companies via our research and development activity.


For more information, please click here

Contacts:
SINTEF Materials and Chemistry
+47 40 00 37 30

Copyright © SINTEF

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

Discoveries

Nanocrystalline cellulose modified into an efficient viral inhibitor April 15th, 2014

Tiny particles could help verify goods: Chemical engineers hope smartphone-readable microparticles could crack down on counterfeiting April 15th, 2014

A molecular approach to solar power: Switchable material could harness the power of the sun — even when it’s not shining April 15th, 2014

Targeting cancer with a triple threat: MIT chemists design nanoparticles that can deliver three cancer drugs at a time April 15th, 2014

Materials/Metamaterials

Engineers develop new materials for hydrogen storage April 15th, 2014

Industrial Nanotech, Inc. Lands First Major Order from Pemex, Mexico’s State-Owned Oil and Gas Company April 14th, 2014

Properties of Coatings Used in Electrical Insulators Modified by Iranian Researchers April 14th, 2014

Graphene Supermarket to offer HDPlas™ by Haydale, a High-Performance Graphene Material April 10th, 2014

Announcements

Aerotech X-Y ball-screw stage for economical high performance Planar positioning April 16th, 2014

Energy Research Facility Construction Project at Brookhaven Lab Wins U.S. Energy Secretary's Achievement Award April 16th, 2014

Malvern reports on the publication of the 1000th peer-reviewed paper to cite NanoSight’s Nanoparticle Tracking Analysis, NTA April 16th, 2014

Biologists Develop Nanosensors to Visualize Movements and Distribution of Plant Stress Hormone April 15th, 2014

NanoNews-Digest
The latest news from around the world, FREE







  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More














ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE