Page 51 - Plastics News April 2022

TECHNOLOGY

New Polymer Membrane Tech Improves Efficiency

cause CO2/nitrogen dioxide mixtures situation in which one needs to remove
are particularly relevant in the context CO2 from mixed gases -- whether it's
of reducing greenhouse gas emissions a biomedical application or scrubbing
from power plants," says Rich Spontak, CO2 from the air in a submarine." "In
co-corresponding author of a paper on short, with little change in permeability,
the work. "And we've demonstrated we've demonstrated that we can increase
that we can vastly improve the selectiv- selectivity by as much as about 150
ity of membranes to remove CO2 while times," says Marius Sandru, co-corre-
sponding author of the paper and senior
esearchers from the North Caro- retaining relatively high CO2 perme- research scientist at SINTEF Industry,
Rlina State Universityhave developed ability." "We also looked at mixtures of an independent research organization
a new membrane technology that al- CO2 and methane, which is important in Norway. "So we're capturing much
lows for more efficient removal of car- to the natural gas industry," says Spon- more CO2, relative to the other species
bon dioxide from mixed gases, such as tak, who is a Distinguished Professor of in gas mixtures." Our next steps are to
emissions from power plants and ap- Chemical and Biomolecular Engineer- see the extent to which the techniques
plication of this technology could be ing and Professor of Materials Science we developed here could be applied to
highly helpful in Chemical and further & Engineering at North Carolina State other polymers to get comparable, or
biomedical applications. We looked University. "In addition, these CO2- even superior, results; and to upscale the
at mixtures of CO2 and nitrogen, be- filtering membranes can be used in any nanofabrication process," Sandru says.

Enhancing The Electromechanical Behavior Of A Flexible Polymer

out to improve this because the relative from 10% efficiency before." This ro-
softness of polymers makes them ex- bust electromechanic performance,
cellent candidates for soft sensors and which is more common in stiff ceramic
actuators in a variety of areas, includ- materials, could enable a variety of ap-
ing biosensing, sonar, artificial muscles plications for the flexible polymer. This
and more." To create the material, the could be applied for use in medical im-
researchers deliberately implemented aging, underwater hydrophones or pres-
chemical impurities into the polymer. sure sensors. Polymers also tend to be
This process, known as doping, allows more lightweight and configurable than
researchers to tune the properties of a ceramics, so this polymer could pro-
iming Zhang, distinguished pro- material to generate desirable effects vide opportunities to explore improve-
Qfessor of electrical engineering -- provided they integrate the correct ments in imaging, robotics and more,
and a Pennislyvania State-led team of number of impurities. Adding too little Zhang said. Other contributors to this
interdisciplinary researchers developed a of a dopant could prevent the desired work include Xin Chen, with the Pen-
polymer with robust piezoelectric effec- effect from initiating, while adding too nyslyvania State Department of Ma-
tiveness, resulting in 60% more efficient much could introduce unwanted traits terials Science and Engineering in the
electricity generation than previous it- that hamper the material's function.The College of Earth and Mineral Sciences;
erations. They published their results efficiency of the polymer's electricity Hancheng Qin, Bing Zhang, Wenchang
in Journal of Science. "Historically, the generation was vastly increased," Zhang Lu and J. Bernholc with North Caro-
electromechanics coupling of polymers said. "With this process, we achieved a lina State University; Xiaoshi Qian with
has been very low," Zhang said. "We set 70% efficiency -- a vast improvement Shanhai Jiao Tong University in China.

51 PLASTICS NEWS April 2022