Self-Healing Water-Repellant Material
A lot of research is being conducted on hydrophobic materials as they have great potential for everything from self-cleaning windshields to getting every last drop out of a condiment bottle, but currently those materials tend to be fragile or can lose their hydrophobic properties by a scratch. So a team of scientists at the University of Freiburg in Germany are trying to address that issue with one possible solution — make water repellent coatings that are self-healing.
Inspired by natural water-repellent surfaces like water plants, the team’s superhydrophobic material sheds it outer skin like a snake in order to repair itself after being damaged. Their material is made of three layers that includes a top layer of hydrophobic film known as nanograss, followed by a layer of a water-soluble polymer used in various medical applications, and at the bottom is a superhydrophobic silicon nanograss film.
The idea behind the material is that if the top layer is damaged, the material can be soaked in water, dissolving the middle polymer layer, allowing the top layer to come loose and slough off, in turn, exposing the fresh hydrophobic layer beneath.
The skin-shedding material is still being researched to strengthen the top layer to prevent scratches damaging the lower layers.
SO, WHAT DO YOU THINK?
Do you think this multilayered approach could lead to more resilient self-cleaning and water-repellent materials? What sorts of applications would this material be good for? Tell us what you think by leaving your comments below.
Recyclable Carbon Fiber
As companies in the aerospace, energy and other industrial sectors increasingly rely on high-strength, lightweight carbon fiber materials, scientists voice concerns about how to properly dispose of them.
Conventional plastics can be melted down and recycled relatively easily, but carbon fiber plastics — particularly those used to build airplanes — are thermosets, or cured plastics.
That process makes them strong, but it also makes them difficult to break down.
Engineers from Washington State University, however, could have a solution.
They deployed mild acids as catalysts in moderately heated liquid ethanol, which allowed the resins in the plastic to expand and the bonds between carbon and nitrogen to break down.
Researchers were also able to preserve both the resin and the carbon fiber, unlike previous attempts that utilized machine grinding, harsh chemicals or very high temperatures.
The process isn't just about preventing plastic materials from entering landfills. Carbon fiber is expensive, and reusing its components could help lower the cost for manufacturers.
SO, WHAT DO YOU THINK?
Could this lead to more use of carbon fiber plastics in other applications? Tell us your thoughts in the comments below.