Page 57 - Plastics News March 2019

TECHNOLOGY

A better way to make plastics out of sulfur

cientists at the University of Liverpool have discovered inverse vulcanization that reduces the required reaction
Sa new process to make polymers out of sulfur which times and temperatures, whilst preventing the production
could provide a way of making plastic that is less harmful of harmful by-products. It also increases the reaction
to the environment. Sulfur is an abundant chemical yields, improves the physical properties of the polymers,
element and can be found as a and allows a wider range of crosslinkers to be used.
mineral deposit across the world. Synthetic polymers are ubiquitous to human life and are
It is also a waste product from among the most extensively manufactured materials on
the refining of crude oil and gas earth. However, with nearly 350 million tonnes of plastic
in the petrochemicals industry, produced annually, coupled with increasing environmental
which generates huge stockpiles concerns and decreasing petrochemical recourses, there
of sulfur outside refineries. Whilst is an urgent need to develop new polymers that are
being identified as an interesting more sustainable. Dr Tom Hasell, Royal Society University
possible alternative to carbon in Research Fellow at the University, whose group conducted
the manufacture of polymers, the research, said: "Making polymers (plastics) out of sulfur
sulfur cannot form a stable is a potential game changer. To be able to produce useful
polymer on its own but, as revealed in a process called plastic materials from sulfur, a by-product of petroleum,
'inverse vulcanization' it must be reacted with organic could reduce society's reliance on polymers made from
petroleum itself. In addition, these sulfur polymers may
crosslinker molecules to make it stable. This process be easier to recycle, which opens up exciting possibilities
can require high temperatures, long reaction times, for reducing current use of plastics. The properties of
and produce harmful by-products. However, researchers sulfur are very different to carbon, and this has already
from the University of Liverpool's Stephenson Institute opened up a world of possible applications for sulfur
of Renewable Energy, working in the field of materials polymers including thermal imaging lenses, batteries,
chemistry have made a potentially game changing water purification and human health. "This research now
discovery. In a study published in Nature Communications, marks a significant step forward in the development of
they report the discovery of a new catalytic process for inverse vulcanized polymers.

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