Here's something I bet you've never heard of before...... Pretty soon, if these bunch of scientists have their way, tearing paper may become harder than ripping through a sheet of iron!!Scientists at the Swedish Royal Institute of Technology in Stockholm have come up with a new form of nanopaper which possesses extraordinary strength even though it is produced from cellulose, a biological material found in conventional paper.
In plant cell walls individual cellulose molecules bind together to produce fibres around 10 nanometres in radius. (Multiply that into 1000, and you get the width of a human hair!!). These fibres form tough networks that provide the cell walls with structural support.
"Cellulose nanofibres are the main reinforcement in all plant structures and are characterised by nanoscale dimensions, high strength and toughness" Said a scientist associated with the project.
Until now, cellulose has only been used as a cheap filler material, and its mechanical properties have completely been ignored.
Mechanical testing shows that the nanopaper has a tensile strength of 214 Megapascals, making it stronger than cast iron (130 MPa) and almost as strong as structural steel (250 MPa)!!
Normal paper, the ones you rip through when you've had a bad day, has a tensile strength less than 1 MPa. So, tearing through this nanopaper is equivalent to tearing through more than 200 sheets of "normal paper"!!!
The secret to the nanopaper's performance is due to the strength of unharmed cellulose and the network formation of cellulose strings. Although strongly bound together, they are still able to slide over each other to dissipate strain.
This new "nanopaper" could be used to reinforce conventional paper, produce "extra-strong" sticky tape or help create tough synthetic replacements for biological tissues --Lars Berglund, Swedish Royal Institute of Technology
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