By Keith Nuthall, Plastics & Rubber Weekly, a Crain publication
Canberra, Australia -- Australian scientists claim to have discovered molecular information proving that many plastics are not as inherently brittle as is currently thought and can be strengthened through improved manufacturing processes.
Researchers at the Canberra-based Australian National University have used supercomputers and quantum chemistry to model polymer degradation, and their work will be published in an upcoming edition of the Royal Society of Chemistry journal, Organic & Biomolecular Chemistry.
Working at the university's Australian Research Council (ARC) Centre of Excellence for Free Radical Chemistry and Biotechnology, the scientists dismissed assumptions that plastics left in the sun, such as clothing pegs, inevitably become brittle through autoxidation. This involves light or heat generating free radicals which attack polymeric chains within a plastic, causing a chain reaction that weakens them, ultimately leading to the failure and breakage of a plastic item.
However, the research suggests that most plastics should actually be inherently resistant to this problem, and are vulnerable to it because of tiny manufacturing defects within most polymer chains. Improving manufacturing reaction conditions and choosing more resistant polymers could yield more resistant materials and longer-lasting plastics and will be identified within the journal.
Researcher Anya Gryn'ova said: "The good news is that if you can remove these defect structures you could greatly improve the stability of many plastics." And study leader, associate professor Michelle Coote, added: "We have uncovered critical information about creating longer-lasting plastics which is important if we want to reduce the amount of plastic waste entering landfill every year."
There were no specific references to polyurethanes in the initial announcement from the RSC.