A new material that transforms at a given time could have potential medical applications, according to New Scientist.
Scientists at the University of North Carolina at Chapel Hill have created a type of putty that can transform over time because of an internal clock. The university team, led by professor Sergei Sheiko, tweaked the molecular structure of a conventional soft polymer to create a material that could be programmed to change shape.
Polymers feature molecules that lie next to each other and which can uncoil and slide past each other, making the material flexible. Only a small proportion of links between molecules in a polymer are permanent, which allows the material to return to its original form when stretched.
The researchers found that they could modify the rate of a polymer’s shape-shifting properties, which allowed them to control how the material changed over the course of several hours.
To demonstrate the material’s ability, the researchers created designs that changed shaped over time. They created a delivery box that opened on one side when it reached its destination. More impressively postgraduate student, Qiaoxi Li created a flower out of multiple parts which were activated at different times to create the effect of blooming. The effect is stunning and displays how the material can be programmed to change shape at different times and intervals.
The material could be particularly useful in biomedical engineering. Medical implants could be designed to be easily inserted into the body, before changing shape inside. The result would be a fairly non-invasive surgery.
This new material is different to other types of morphing materials which can only change shape due a trigger, such as light, temperature or pH. Professor Sheiko spoke about the issues of application of triggers saying: “In certain situations, like inside your body or in space, external triggers are not permissible or are ineffective. You simply want an object to change shape at a given moment.”
Professor Sheiko said the team are looking to explore the material further.