Page 92 - Plastics News August 2024
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IN THE NEWS
waste. contaminated plastics.
NTU scientists have developed a synthetic ma- Researchers from NTU explored using difficult-
trix to culture cells using ABS from discarded to-recycle plastics as a source of solid carbon
keyboards. The matrix is porous like a sponge material for application in polymer foams. The
and functions as a support structure, providing a researchers first obtained gas and oil by heat-
framework for cells to attach and grow. ing different types of plastic waste at high tem-
peratures (600 degrees Celsius) in the absence
The matrix can culture spherical clusters of cells, of oxygen. Then the gas and oil were heated at
called cancer spheroids, that resemble actual over 1000 degrees Celsius to break down the
tumours. Due to their 3D shape, these “mini tu- molecules into solid carbon and hydrogen. The
mours” more accurately represent tumours than solid carbon can be added to polymer foam to
conventional cell cultures. increase its strength and resistance to abrasion
for cushioning applications. The foam containing
To fabricate the matrix, the scientists dissolved
plastic scraps from discarded keyboards in an the synthesised solid carbon derived from plas-
organic solvent, acetone and poured the solu- tic waste exhibited properties comparable to
tion into a mould. other carbon-based and conventional reinforc-
ing materials available on the market.
The matrix supported the growth of breast, colo-
rectal and bone cancer spheroids. The cancer At the same time, the hydrogen produced could
spheroids had properties similar to those grown be collected and used as fuel.
using commercially available matrices and may A bright way to break down plastics into valu-
be used for biomedical applications such as drug able compounds
testing.
Although plastics can be broken down by heat-
“Our innovation not only offers a practical means ing them at high temperatures, such processes
to reuse e-waste plastics but could also reduce are energy intensive and generate greenhouse
the use of new plastics in the biomedical indus- gases, contributing to global warming.
try,” said Assoc Prof Dalton Tay of NTU’s School
of Materials Science and Engineering, who led Addressing the need for greener methods of
the research. breaking down plastics, NTU scientists have de-
veloped a process that can upcycle most plas-
Converting hard-to-recycle plastic tics into chemical compounds useful for energy
waste into hydrogen and carbon addi- storage. The reaction uses light-emitting diodes
tives for polymer foams (LEDs) and a commercially available catalyst and
occurs at room temperature. It can break down
While some types of plastics can be repurposed
into new products, it is not as easy to recycle a wide range of plastics, including polypropyl-
other kinds of plastics. Household plastics, pack- ene, polyethylene and polystyrene, all common-
aging waste and marine plastic litter recovered ly used in packaging and discarded as plastic
from the environment are all examples of plastic waste.
waste that are difficult to recycle. There are also Compared to conventional plastic recycling
limited economic benefits to treating mixed and
94 PLASTICS NEWS August 2024
