Surface and interfacial tensions are phenomena that affect our everyday life. We can find numerous examples where surface tension plays a role. Take a classic example of a spider walking on the surface of the water. Change water to ethanol and the poor spider will drown. Why? Because the surface tension of water is high enough to support the weight of the spider but with much lower surface tension, ethanol can’t do the same. The high surface tension of water is also the reason why rain comes down as a spherical drop. High surface energy drives the water drop to take a shape with as little surface area as possible, making a sphere shape the most favorable.
Now you might think that who cares about the spider, they can stay on dry land. And the water drop shape is not really that important either. But the thing is that if the surface tension of water would be much lower, nothing would really float on top. Even the smallest particles would sink to the bottom causing the failure of the ecosystem. And furthermore, there would not really be water in a liquid form as it would simply evaporate into the atmosphere.
By now, I hope you are convinced that surface tension is needed to have life as we know it. If we move away from fundamental problems that would arise if surface tension wouldn't exist, we can see that it is a highly important parameter also in many industrial processes.
Surface and interfacial tension are key factors in many industrial processes
Surface and interfacial tension play a key role in product development. R&D departments around the world are measuring surface and interfacial tension to improve the quality of their products. Detergent formulations are optimized with the help of critical micelle concentration measurements to improve their cleaning properties with lower amounts and more ecological surfactants at lower temperatures. Paints are tailored with the help of wetting agents to stick better on the surfaces they are applied to and drugs are developed to improve their effectiveness. Surface tension is key in understanding the stability of emulsions in various applications. These are just a few of the numerous examples that can be mentioned.
To read more about how surface and interfacial tension measurements are utilized in different industrial areas, please download the overview below.