Thursday, June 14, 2007

Researchers Look to Nature to Improve the Healing Properties of Artificial Surfaces

Scientists at the University of Illinois have developed a polymer skin that heals itself when damaged. Their model for the technique: Mother Nature.
Nancy Sottos tells Nature Materials, 'Healing in biological systems is accomplished by a pervasive vascular network that supplies the necessary biochemical components. A cut in the skin triggers blood flow from the capillary network in the dermal layer to the wound site rapidly forming a clot... minor damage to the same area can be healed repeatedly.'
This sort of self-healing has been seen before in artificial membranes, but what differs with this new technology is that damaged areas can heal more than once. Previous systems healed because they contained unreacted polymer capsules that when broken reacted to form a seal. But this technology takes healing one step further.
'After damage occurs at the coating, healing agent wicks from the microchannels into the crack(s) through capillary action,' the researchers report in Nature Materials. 'Once in the crack plane the healing agent interacts with the catalyst particles in the coating to initiate polymerisation, rebonding the crack faces autonomically. After a sufficient time period the cracks are healed and the structural integrity of the coating restored. As cracks reopen under subsequent loading the healing cycle is repeated.'
This new system will be invaluable to materials science, and its possibilities will be endless.
While the technology of self healing polymers mimics natural systems, one thing it lacks is its ability to break down to be reused in the system. Let's hope in the future we look to nature to figure out how to create polymers that last so long as we need them, and as the flower that has been pollinated returns to the soil to provide future resources, our products will also return to futher the cycle.
for the article in RSC
My friend Robyn at Biomimicry Institute found this video of the polymer healing

1 comment:

  1. Excellent article - and a great catch. Figuring out the process is tough- this is a good proof of principle for materials scientists to dig their teeth into....

    Also good point about life-cycle analysis of materials. I also would like a more sustainable approach to the actual fabrication- the current technique uses lot's of heating, melting, and materials I'm not too familiar with...Someone also mentioned to me how the catalyst on the exterior of this model might not be a good place for a catalyst. The idea of multiple networks in the material is better.