Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Pearls to Prevent Relaxation

29.04.2014

Additive stops aging in super glassy polymer membranes

Putting a stop to aging has now been made possible for highly porous polymer membranes whose efficiency in the separation of gases falls off fast when parts of their polymer chains rearrange, as so do their pores.

In the journal Angewandte Chemie , a team of Australian and American researchers has now introduced a method for preventing this relaxation of the polymer chains: special porous particles made of an aromatic framework incorporate the polymer chains and hold them in their original position.

Separation processes like purification and adsorption are especially energy-intensive procedures; it is thus correspondingly important to find alternatives to replace existing technologies.

One possible approach is gas separation using polymer membranes. The theory behind this separation technique is that different gases pass through the membrane at different rates. This allows for the separation of CO2 from nitrogen, for example, which is relevant for carbon capture from flue gases. Currently, liquid absorbents that operate in a batch rather than continuous process are typically used.

The polymer membranes used must be extremely porous, so that as much of the surface area as possible is accessible to the gas molecules. It is no problem to produce highly porous membranes by using the appropriate “molds”.

However, any celebration of the high separation performance of these super glassy membranes, as they are known, does not last long as the membranes “age”. Despite the rigid state of the polymer, individual polymer segments are not fully “frozen” into position but can move to some extent. For thermodynamic reasons, the polymer chains attempt to stay as evenly distributed as possible.

This also causes them to fill the empty space within the pores. Because of their residual mobility, the polymer chains “relax” little by little, slowly reducing the free volume of the pores. The separation performance of the membrane falls off correspondingly. It has not previously been possible to effectively halt this process.

Led by Matthew R. Hill and Richard D. Noble, a team from the Division of Materials Science and Engineering at the Commonwealth Scientific and Industrial Research Organization (CSIRO) and the University of Colorado (USA) has now developed a method that prevents aging of super glassy membranes.

The trick is to include a specific additive during production of the membranes. The additive consists of porous microparticles made of a special three-dimensional framework of aromatic compounds and carbon atoms. The microparticles are strung along the particle chains like pearls on a string. This causes the chains to be “frozen” in place.

The pores remain as open as they were when first manufactured and the membrane does not age. As a side effect, the porous aromatic microparticles improve the ability of the membranes to separate nitrogen and carbon dioxide up to three-fold.

About the Author

Dr. Matthew Hill is a senior research scientist with the CSIRO, Australia’s national science agency. He specialises in ultraporous materials with applications in separation, storage and triggered release. He is a 2014 awardee of the MIT Technology Teview ‘Innovators under 35’ award for the South-East Asia region.

Author: Matthew R. Hill, CSIRO Division of Materials Science and Engineering, Clayton South (Australia), https://wiki.csiro.au/display/MEWE/Matthew+Hill

Title: Ending Aging in Super Glassy Polymer Membranes

Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201402234

Dr. Matthew Hill | Angewandte Chemie
Further information:
http://pressroom.angewandte.org

Further reports about: Aging Engineering Membranes Polymer Relaxation Super compounds volume

More articles from Life Sciences:

nachricht A Map of the Cell’s Power Station
18.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht On the way to developing a new active ingredient against chronic infections
18.08.2017 | Deutsches Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>