Natural fluff resistant to water? Such an effect thanks to the "cold plasma" obtain the scientists from Lodz

Fabrics and ceramic tiles on which water flows down, cleaning the surface; natural down that maintains its thermal properties even if water enters it – these are some of the developments of researchers at the Technical University of Lodz using the so-called “superhydrophobic” plasma. cold plasma.

Prof. Jacek Tyczkowski of the Faculty of Process Engineering and Environmental Protection at the University of Łódź reminded that plasma is the fourth state of matter – after solid, liquid and gas. It is a gas in an ionized state, which is a mixture of free electronsoin, ionow, radicalow, ionorodnikow, excited molecules. From the ratio of these elementow depends on what kind of plasma we are dealing with – explained.

Plasma forms stars m.in. sun (so-called. hot plasma), occurs in fluorescent lamps, in lightning discharges or in aurorae. One of its types has been applied in chemical technologyoin, the so-called. cold plasma (nierow nova), ktora is used to produce new materialoin, whether to modify their surface.

– In the so-called. cold plasma high energy has only electrons, while all other components have a temperature close to room temperature. Hence, the products of any chemical transformations are not destroyed. That is why it is so valuable and interesting for chemical technology,” stressed Prof. Jacek Tyczkowski.

Plasma offers the possibility of producing completely new materialsow in the form of very thin nanostructured layers with sometimes fascinating properties, ktowhich cannot be obtained by other methods. Such plasma can be used roalso for surface modification of conventional materialsow, changing their properties completely.

– We can, for example. make such a surface no longer willing to come into contact with water and become hydrophobic or even superhydrophobic. If we properly modify it with plasma, water droplets already after a slight inclination of it, fall from it entraining particles of impurities. This is a self-cleaning surface phenomenon known from nature, as it was first observed on lotus leaves and hence its name "lotus effect" – explained the expert.

One can – using plasma – also obtain the opposite effects and produce hydrophilic or superhydrophilic layers, whichore perfectly wetted and covered with water. It also manages to change the adhesion (clinging) properties of materialoin and improve e.g. bonding properties of such surfaces. – As for modifying the surface using plasma, there are many possibilities, the scientist stressed.

Teamoł researchers from the Faculty of Process Engineering and Environmental Protection of the University of Łódź have already developed a m.In. plasma method of modifying the surface of fabrics. Using plasma, superhydrophobic layers were created on fabrics, making the water, whichora before the RPMowith plasma soaked into the fabric, after such a rotationobce flows over it and causes a self-cleaning effect. This solution can be used m.in. for the production of rainwear.

The researchers are currently working on a method to modify ceramic tiles m.in. for bathrooms. The result of this research is expected to be tiles, after which ktoThe result of this research is expected to be tiles that will be water-repellent and will not need to be cleaned or dried too often after bathing. Such an effect roAlso manages to be obtained by appropriate treatmentobk in plasma. – Drops on such plates flow down like on lotus leaves and clean their surface, the scientist pointed out.

Researchers have also used plasma to modify the surface of natural down. Down is a great insulating material, but provided it is not wet. Then it loses its thermal properties. In this case, the challenge was to develop a method thatora will make it impossible for water to wet the down.

– On the surface of the pior down is applied to a thin nanostructure. Down thus gains aob a barrier of protection, whichora makes it so that even if water enters it, it is unable to dampen the down and its droplets remain completely independent of it,” recounted Prof. Tyczkowski.

Such plasma fluff has already been tested in suits for Himalayan climbersow m.in. During the recent National Expedition to K2. – Thanks to the use of plasma down, even if you fall into the water in such a suit, it remains dry inside and retains its thermal properties, the expert added.

Another project łodz scientistsoin, ktory also succeeded, concerns the modification of the surface of rubbers used, as soles for shoes, when preparing them for the process ofoin bonding. According to the scientistow, the revolutionary nature of this method is to change the technology previously used in the shoe industry.

Until now, such rubber surfaces have been activated chemically, using organic solvents and volatile chlorine compounds, ktore are harmful to humans and the environment. In turn, thanks to the use of plasma, a clean, waste-free technology has been developed „green chemistry”. Better results were also obtained than with classical chemical methods.

Sourceobackground: PAP – Science in Poland. Pictured is the surface of a lotus leaf under high magnification. Photo. William Thielicke/ Wikimedia Commons/