In worst-case scenarios, tens of millions of arthritis patients worldwide require painful surgeries that drill holes in joints and reinforce them. A promising new synthetic cartilage hydro-gel now offers hope for the afflicted….click & see the pictures
Researchers at the US National Institute of Standards and Technology (NIST) have identified a gel that, while having the pliancy of gelatin, won’t break apart even when deformed over 1,000%.
Known as double-network hydro-gels, the incredible strength of these new materials was a happy surprise discovery by researchers at Hokkaido University, Japan, in 2003. The Japanese team discovered that addition of a second polymer to the gel made them so tough that they rivalled tissues that can withstand the abuse of hundreds of pounds of pressure.
Most conventionally prepared hydro-gels materials that are 80-90% water held in a polymer network easily break apart like gelatin. But not this one.
By using NIST’s neutron research facility to show how the molecules in the gel sustain such large deformations, the research team hopes to make it easier to design materials with even better mechanical properties.
Initial work using NIST’s neutron scattering techniques to explore the structure of the gel found unexpected results.
The two polymers were attracted to each other, despite the fact that one polymer is negatively charged and the other neutral. They can withstand a certain force before they are pulled apart.
The total amount of force that can be endured by this polymer pair gets amplified enormously because there are many contacts along each long chain. Efficacy of stress transfer between the long added chain and gel net-work forms the cornerstone of the toughening mechanism in DN-gels.
Sources: The Times Of India