Waterproofing with Nano-coatings

With Hurricane Sandy just rapping up in New Jersey and New York, a lot of people have lost power, water and may have even been flooded. The classic pitfall for all people in this situation with electronics; to drop your brand new IPhone five into a puddle. P2i attempts to solve this problem with nanotechnologies by making a water repellent nano-coating.

Note that they did not say that their product is water resistant or waterproof. They just say that it is water repellent, or rather, that it makes other's product water repellent. The difference between these three are subtle, but still present. Something that is waterproof probably does not exist, because that would suggest that it a technology would survive under even the highest of pressures. This is obviously not the case. A more correct term is water resistant, which is what has become common in watches.

Being water repellent is completely different. instead of working with water or keeping it out, being water repellent is making the water 'go away'.

Figure 1: Why water sticks to itself diagram

Water has a property of coherence, (the state of cohering or sticking together, figure 1) This property is what creates the curve in water when you look at it in a cup from the side (figure 2). To be clear, figure one is not the only type of meniscus. There are both concave and convex menisci. For example in figure 2, there is both a concave and convex example. The water is concave (because it turns inwards) and mercury is convex (it turns outwards). This is decided by how much the liquid in a container sticks to itself and how well the liquid sticks to the material of the container. If the substance sticks more to itself than the container (because the surface energy of the container is higher than that of the water), then it is convex like mercury, otherwise, it is concave.

Figure 2: curvature in water because of coherence as well
as a meniscus

Figure 3: comparing a concave and convex menisci

This is the fundamental property behind P2i and describes a water repellent material. To be water repellent, water needs to ball up and roll off of a material when it is splashes on the surface of something. This requires that the surface energy be lower than waters. P2i does just that, it lowers the surface energy of a material, making water roll off of it like skies sliding down a snow capped mountain.

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This is a video of how they lower the surface area of a technology:

P2i is not only interested in saving phones in technologies, but also for other, more common things. They are water repelling  footwear, hats, gloves, life sciences, flitration, energy. It is also used to help the military and institutions.
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