Featured Research

from universities, journals, and other organizations

Transparent polymeric films with near-uniform, continuous nanoprotrusions show high water pinning abilities

Date:
August 14, 2014
Source:
The Agency for Science, Technology and Research (A*STAR)
Summary:
Researchers have used nanoimprinting methods to make patterned polymeric films with surface topography inspired by that of a rose petal, producing a range of transparent films with high water pinning forces.

A water droplet adheres to a patterned polycarbonate film even when held vertically.
Credit: 2014 A*STAR Institute of Materials Research and Engineering

A*STAR researchers have used nanoimprinting methods to make patterned polymeric films with surface topography inspired by that of a rose petal, producing a range of transparent films with high water pinning forces.

Related Articles


A surface to which a water droplet adheres, even when it is turned upside down, is described as having strong water pinning characteristics. A rose petal and a lotus leaf are both superhydrophobic, yet dissimilarities in their water pinning properties cause a water droplet to stick to a rose petal but roll off a lotus leaf. The two leaf types differ in their micro- and nanoscale surface topography and it is these topographical details that alter the water pinning force. The rose petal has almost uniformly distributed, conical-shaped microscale protrusions with nanoscale folds on these protrusions, while the lotus leaf has randomly distributed microscale protrusions.

The imprinted surfaces developed by Jaslyn Law and colleagues at the A*STAR Institute of Materials Research and Engineering and the Singapore University of Technology and Design have uniformly distributed patterns of nanoscale protrusions that are either conical or parabolic in shape. The researchers found that the water pinning forces on these continuously patterned surfaces were much greater than on non-patterned surfaces and surfaces composed of isolated nanopillared structures or nanoscale gratings. They could then achieve high water pinning forces by patterning the nanoprotrusions onto polymeric films with a range of different non-patterned hydrophobicities, including polycarbonate, poly(methyl methacrylate) and polydimethylsiloxane.

"Other methods that recreate the water pinning effect have used actual rose petals as the mold, but unless special care is taken, there are likely to be defects and inconsistencies in the recreated pattern," says co-author Andrew Ng. "While bottom-up approaches for making patterns -- for example, laser ablation, liquid flame spray or chemical vapor deposition -- are more consistent, these methods are limited in the types of patterns that can be used and the scale at which a substrate can be patterned."

In contrast, nanoimprinting methods are capable of fabricating versatile and large-scale surfaces, and can be combined with roll-to-roll techniques, hence potentially enabling more commercial applications.

The patterned polycarbonate surfaces were also shown to reduce the 'coffee-ring' effect: the unevenly deposited film left behind upon the evaporation of a solute-laden droplet. This mitigation of the coffee-ring effect may assist microfluidic technologies and, more generally, the patterned surfaces could be used in arid regions for dew collection or in anti-drip applications such as in greenhouses.


Story Source:

The above story is based on materials provided by The Agency for Science, Technology and Research (A*STAR). Note: Materials may be edited for content and length.


Journal Reference:

  1. Jaslyn Bee Khuan Law, Andrew Ming Hua Ng, Ai Yu He, Hong Yee Low. Bioinspired Ultrahigh Water Pinning Nanostructures. Langmuir, 2014; 30 (1): 325 DOI: 10.1021/la4034996

Cite This Page:

The Agency for Science, Technology and Research (A*STAR). "Transparent polymeric films with near-uniform, continuous nanoprotrusions show high water pinning abilities." ScienceDaily. ScienceDaily, 14 August 2014. <www.sciencedaily.com/releases/2014/08/140814003755.htm>.
The Agency for Science, Technology and Research (A*STAR). (2014, August 14). Transparent polymeric films with near-uniform, continuous nanoprotrusions show high water pinning abilities. ScienceDaily. Retrieved December 22, 2014 from www.sciencedaily.com/releases/2014/08/140814003755.htm
The Agency for Science, Technology and Research (A*STAR). "Transparent polymeric films with near-uniform, continuous nanoprotrusions show high water pinning abilities." ScienceDaily. www.sciencedaily.com/releases/2014/08/140814003755.htm (accessed December 22, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Monday, December 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Will New A350 Help Airbus Fly?

Will New A350 Help Airbus Fly?

Reuters - Business Video Online (Dec. 22, 2014) Qatar Airways takes first delivery of Airbus' new A350 passenger jet. As Joel Flynn reports it's the planemaker's response to the Boeing 787 Dreamliner and the culmination of eight years of development. Video provided by Reuters
Powered by NewsLook.com
Man Parachutes Off Lawn Chair Airlifted By Helium Balloons

Man Parachutes Off Lawn Chair Airlifted By Helium Balloons

Buzz60 (Dec. 22, 2014) A BASE jumper rides a lawn chair, a shotgun, and a giant bunch of helium balloons into the sky in what seems like a country version of the movie 'Up." Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Touch-Free Smart Phone Empowers Mobility-Impaired

Touch-Free Smart Phone Empowers Mobility-Impaired

Reuters - Innovations Video Online (Dec. 21, 2014) A touch-free phone developed in Israel enables the mobility-impaired to operate smart phones with just a movement of the head. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Existing Chemical Compounds Could Revive Failing Antibiotics, Says Danish Scientist

Existing Chemical Compounds Could Revive Failing Antibiotics, Says Danish Scientist

Reuters - Innovations Video Online (Dec. 21, 2014) A team of scientists led by Danish chemist Jorn Christensen says they have isolated two chemical compounds within an existing antipsychotic medication that could be used to help a range of failing antibiotics work against killer bacterial infections, such as Tuberculosis. Jim Drury went to meet him. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins