We encounter plastics, known as polymers, everywhere: in electronics, clothing, sport and leisure - to name just a few examples. Although bio-based materials are now available as ‘greener’ alternatives, their share of global plastics production in 2021 was less than two per cent - a fraction of the total of more than 390 million tonnes. ‘The future of the plastics industry essentially depends on the development of sustainable polymer materials that are obtained from renewable raw materials and are suitable for chemical recycling as part of a circular economy,’ says Prof Dr Thomas Werner from Paderborn University and associated scientist at the Leibniz Institute for Catalysis. The chemist is leading a research project that aims to develop various methods for the chemical recycling of bio-based polymers. The aim is to convert bio-based materials into valuable, reusable products in order to help reduce CO2 emissions and plastic waste. As part of the Leibniz Association's ‘Collaborative Excellence Programme’, scientists from the Leibniz Institute for Catalysis (LIKAT), the Leibniz Institute for Plasma Science and Technology (INP), the Leibniz Institute for Polymer Research (IPF) and Paderborn University are working hand in hand to find solutions. The Leibniz Association is funding ‘SUSTAIN’ - as the programme is called - with around one million euros.
‘There are currently three options for dealing with plastic waste: incineration for energy recovery, which is associated with a large carbon footprint, and mechanical recycling, which often results in a significant loss of performance properties. These limitations have led to an increasing interest in the third option, chemical recycling,’ explains Werner. This primarily involves depolymerisation, i.e. the breakdown of polymers into monomers. Starting materials or smaller fragments should ultimately be reprocessed into high-quality products as part of the repolymerisation process. Werner: ‘We are investigating various approaches with different levels of technological maturity and suitable combinations. The main focus is on the use of catalytic processes. Mechanochemical, electrochemical, photochemical and plasma-based methods are also being used.’
To produce the condensates, several monomers can be obtained from renewable sources through catalytic conversion. ‘Typically, these are oxidised products such as diols and dicarboxylic acids or even diamines,’ explains Werner. It can therefore be expected that bio-based polycondensates will become increasingly important in the future - for industry, end consumers and, above all, for the environment. The team expects initial results in the middle of next year.
This text was translated automatically.
