Everything about The Lotus Effect totally explained
The
lotus effect in
materials science is the observed
superhydrophobic (also super hydrophobic or super-hydrophobic) and self-cleaning property found with
lotus plants' leaves . In some Eastern cultures, the
lotus plant is a symbol of purity. Although lotuses prefer to grow in muddy rivers and lakes, the leaves and flowers remain clean.
Botanists who have studied lotus leaves have found that they've a natural cleaning mechanism. This cleaning mechanism was discovered by Wilhelm Barthlott in 1982. He also holds a patent .
The microscopic structure and surface chemistry of the leaves prevent them from being wetted by liquids having a contact angle of greater than 90° to an unstructured surface of the same material. With
contact angles to water of up to 170°, droplets roll off a leaf's surface like
mercury, taking mud, tiny insects, and contaminants with them. This is known as
superhydrophobicity, or more commonly, the
lotus effect. Water droplets on
taro and
nasturtium leaves exhibit similar behavior.
Some
nanotechnologists have developed treatments, coatings, paints, roof tiles, fabrics and other surfaces that can stay dry and clean themselves in the same way as the lotus leaf. This can usually be achieved using special fluorochemical or silicone treatments on structured surfaces or with compositions containing micro-scale particulates. Super-hydrophobic coatings comprising Teflon™ microparticles have been used on medical diagnostic slides for over 30 years. It is possible to achieve such effects by using combinations of
polyethylene glycol with
glucose and
sucrose (or any insoluble particulate) in conjunction with a hydrophobic substance.
In one method, an
aluminium surface is made
superhydrophobic by immersing it in
sodium hydroxide for several hours (which roughens the surface) followed by
spin coating a layer of
perfluorononane to a thickness of 2
nanometers. This procedure increases the water
contact angle from 67° to 168°, an effect that can be explained by
Cassie's law.
Electron microscopy shows that the aluminium surface resembles that of a lotus surface, with a porous
microstructure containing trapped air. Any surface treatment that creates micro or nano scale roughness with features having a height to width ratio greater than one that's subsequently coated with a thin hydrohobic coating will exhibit the Lotus effect.
Commercial uses
Clothing that repels water has already been developed and marketed by brands such as Gap and Dockers; it uses a fabric named Nano-Care. Water repelling glass panels have also been brought onto the market for use on the roofs of
conservatories. StoCoat Lotusan is an exterior coating (
paint) that mimics the microstructure of the lotus leaf surface, gaining similar water-repellent and self-cleaning properties, termed the Lotus-
Effect. Water doesn't adhere to the surface, but rolls off the paint, picking up and washing away debris in the process. By remaining dry, the coating also resists mold, mildew, and algae. Though hydrophobic, the coating is highly permeable to water vapor. Lotus effect
superhydrophobic coatings applied to microwave antennas can significantly reduce
rain fade and the buildup of ice and snow.
Further Information
Get more info on 'Lotus Effect'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://lotus_effect.totallyexplained.com">Lotus effect Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |
