Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Blending is the Trick: Tailored Pores in Block Copolymer Membranes

06.05.2015

A simple trick generates custom-tailored pores. Maryam Radjabian has developed a surprisingly uncomplicated method for obtaining the desired pore size in block copolymer membranes. The results of her research were published in the distinguished international scientific journal Advanced Materials.

Whether it’s water treatment or virus and protein separation, porous membranes are utilised in many different separation functions. What is particularly fascinating and highly promising is isoporous membrane production from block copolymers.


Tailored Pore Sizes in Integral Asymmetric Membranes Formed by Blends of Block Copolymers

[HZG, Abetz]

Under suitable conditions, block copolymers can form highly ordered structures, ideally uniform pores, through self-assembly (see “Block Copolymer Information” below).

In order to develop effective membranes for special separation functions, the correct pore size is crucial. This objective presents the greatest challenge: how must the block copolymer be composed in order to obtain the desired pore size?

To date, for every newly developed isoporous membrane a special block copolymer was synthesized, which then resulted in the necessary pore size. In cooperation with the director of Geesthacht’s Institute of Polymer Research, Prof. Volker Abetz, Dr. Maryam Radjabian has now developed a time-saving and surprisingly simple method: by blending of two block copolymers, the pore size can be adjusted via the blending ratio.

The two block copolymers consist of the same monomers but differ in the number of repetition units in the blocks. A different pore size then arises in the particular membrane cast from each block copolymer. Dr. Radjabian’s concept of obtaining an average pore size by blending two block copolymers has been corroborated in experiments.

This opens up entirely new possibilities for designing new membranes. The scientist at the Institute of Polymer Research explains, “There is a substantial advantage in not having to synthesize a precisely suitable block copolymer to obtain the desired pore size, but in simply mixing two approximately suitable copolymers together.”

Block Copolymer Information:
Block copolymers consist of at least two types of monomers, each covalently linked together as polymer blocks (a group of the same monomers) in the form of a macromolecule. Because the blocks of macromolecules are selected so that they are not mixable (“immiscible”), self-assembly of the macromolecules takes place through rejection reactions (microphase separation).

Isoporous Membranes can be produced from a block copolymer solution under defined conditions by utilising the phase inversion principle. The foundations for this research were developed within the HZG-coordinated European Union project SELFMEM (2009-2012).

DOI: 10.1002/adma.201404309: Tailored Pore Sizes in Integral Asymmetric Membranes Formed by Blends of Block Copolymers, Maryam Radjabian, Volker Abetz
Advanced Materials 2015, 27, 352-355, (online 20 Nov.V 2014)

Weitere Informationen:

http://www.hzg.de/public_relations_media/news/058880/index.php.en - website HZG
http://dx.doi.org/10.1002/adma.201404309 -- Publication

Dr. Torsten Fischer | Helmholtz-Zentrum Geesthacht - Zentrum für Material- und Küstenforschung

More articles from Materials Sciences:

nachricht Strange but true: Turning a material upside down can sometimes make it softer
20.10.2017 | Universitat Autonoma de Barcelona

nachricht Metallic nanoparticles will help to determine the percentage of volatile compounds
20.10.2017 | Lomonosov Moscow State University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>