Subscribe to our free daily newsletters
. 24/7 Space News .




Subscribe to our free daily newsletters



TECH SPACE
Self-cleaning, anti-reflective, microorganism-resistant coatings
by Staff Writers
Leioa, Spain (SPX) Aug 10, 2016


Detail of the phase separation in the copolymer: when the siloxane (areas where yellow predominates) migrates to the surface, it generates greater roughness, and due to its hydrophobic characteristics, prevents the adhesion of organisms. Image courtesy Alexander Santiago and UPV/EHU. For a larger version of this image please go here.

Coatings or paints are materials applied to different surfaces basically for decorative and protective purposes. Yet today the market for these materials is being subjected to increasingly tougher specifications.

In addition to being decorative and protective, today's coatings must have additional properties such as, for example, low microorganism-adherence, ease of cleaning or self-repair properties. The development of materials of this type, known as "functional coatings", calls for the control not only of their physical properties (mainly to do with their morphology) but also of the chemical ones of the surfaces produced.

The research of Alexander Santiago set out to make a contribution towards the development of three types of functional coatings: ones that are resistant to microorganisms (for example for paints for seagoing vessels), and which have self-cleaning (hydrophobic paints) and anti-reflecting properties (for coating mobile phone screens or spectacle lenses).

Following the thread of other pieces of research conducted not only by members of the research group but also by members of a research group of the IBM Almaden Research Center San Jose in the United States, the researcher carried out numerous trials and tests in the three above-mentioned lines to obtain functional materials with the desired properties.

Reducing costs
The first of the hydrophobic coatings he explored was a type of copolymer that gives rise to spontaneous phase separation between its components. In other words, "one of the components of the copolymer (the polyurethane) gives the substrate adhesion and most of the other component (the siloxane) remains on the surface, which makes it rougher, and as it is also hydrophobic it stops organisms sticking to it," explained Alexander Santiago.

Through various measurements they confirmed that the hydrophobicity of the system depended to a greater extent on roughness than on the siloxane concentration on the surface. Protein absorption measurements were used to determine the restriction of the adhesion capacity of the microorganisms on these films. These trials showed that the microorganisms stuck less to the films displaying phase separation.

To obtain materials that would display a self-cleaning effect (within the line of hydrophobic coatings), inorganic nanoparticles of a hydrophobic nature were synthesised in advance and inserted into acrylic polymers using various methods. Specifically, they were silicon nanoparticles with an organic coating.

The best results were obtained by spraying these nanoparticles onto acrylic films, and that way a super-hydrophobic surface was created offering very good self-cleaning properties in addition to a high level of toughness. The method used "turned out to be a fast and relatively cost-effective one," said the researcher, "as we used silicon that is not as expensive as other substances used on the market."

To obtain anti-reflecting properties, the films need to have a refractive index lower than that of the substrate, which can be achieved by inserting porosity into them. But the presence of the pores prevents the anti-reflecting surfaces from having suitable mechanical properties enabling them to be processed. In this respect, he studied the porosity/toughness relation with respect to the refractive index obtained and the results were promising.

As the researcher explained, "there is still work to be done because, for example, the nanoparticles do not take hold completely and because the final film with the nanoparticles is not as consistent as we would like".

As regards the copolymers studied in relation to the biological anti-contamination properties, he said that "the early results were fairly favourable," and added that "they could be extrapolated, but the problem is that we are working on a laboratory scale". Finally, the researcher explained that the subject of anti-reflective coatings was only at the early stages of research and "we are still improving it".

Santiago, L. Irusta, T. Schafer, A. Corres, L. Martin, and A. Gonzalez. "Resistance to protein sorption as a model of antifouling performance of Poly(siloxane-urethane) coatings exhibiting phase separated morphologies". Progress in Organic Coatings 99, p: 110-116 (2016).

Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only

.


Related Links
University of the Basque Country
Space Technology News - Applications and Research






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Previous Report
TECH SPACE
Nothing - and something - give concrete strength, toughness
Houston TX (SPX) Aug 12, 2016
What does one need to strengthen or toughen concrete? A lot of nothing. Or something. The "nothing" is in the form of microscopic voids and the "something" consists of particular particles embedded in the most common construction material on Earth. Rice University materials scientist Rouzbeh Shahsavari and postdoctoral researcher Ning Zhang analyzed more than 600 computer models of concret ... read more


TECH SPACE
Lockheed Martin, NASA Ink Deal for SkyFire Infrared Lunar Discovery Satellite

As dry as the moon

US company gets historic nod to send lander to moon

China's Jade Rabbit lunar rover dies in blaze of online glory

TECH SPACE
Opportunity going back for closer look at grooves seen in images

Limited power as Mar Lab approaches Murray Buttes

Mineral Veins on Mars Were Formed by Evaporating Ancient Lakes

Evidence of Martian life could be hard to find in some meteorite blast sites

TECH SPACE
Commercial Crew Astronauts Discuss Progress, Training with Employees

Autonomous interplanetary travel one step closer to reality

After Deadly Crash, Virgin Galactic to Fly Its Spaceplane Once More

Tile Bonding Begins for Orion's First Mission Atop Space Launch System Rocket

TECH SPACE
China launches hi-res SAR imaging satellite

China launches world first quantum satellite

China launches first mobile telecom satellite

China prepares for new round of manned space missions

TECH SPACE
NanoRacks External Platform Deployed Outside International Space Station

Russia Could Cut Down International Space Station Crew

NASA mulls Russian idea to cut staff at space station

JSC pursues collection of new technologies for ISS

TECH SPACE
Launch of US Antares Rocket Powered by Russian Engine Postponed

Preparations for Arianespace's upcoming Ariane 5 flight move into their final phase at the Spaceport

Seoul Confirms Russian Carrier Rocket to Put Korean Satellite Into Orbit in 2020

New payload preparation milestones bring Ariane 5's upcoming mission closer to liftoff

TECH SPACE
Scientists to unveil new Earth-like planet: report

Astronomers catalogs most likely 'second-Earth' candidates

Alien Solar System Boasts Tightly Spaced Planets, Unusual Orbits

NASA's Next Planet Hunter Will Look Closer to Home

TECH SPACE
Sierra Nevada Corporation helps Juno "Keep Cool and Science On"

Stanford scientists consider 3D printing Mars rock samples

New method helps stabilize materials with elusive magnetism

Self-cleaning, anti-reflective, microorganism-resistant coatings




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News






The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement