Researchers from the Nagoya University have created a catalyst that works under mild conditions, which can be used to process plastics. Scientists presented the results of their work in the journal Scientific Reports.
The protein and nylon from which, for example, jackets are made, have something in common. They are polymers whose monomer units are bound by amide bonds. These strong chemical bonds are found not only in proteins, but also in other biomolecules, for example in urea. Urea serves as a starting material in the synthesis of certain plastics.
Amid bonds provide high strength to different plastics, but when it comes to processing, breaking these ties becomes a challenge. This means that it is not possible to extract chemical compounds from an unfit plastic material, which can still be used.
The destruction of amide bonds in a synthetic polymer requires severe conditions and a large amount of energy. But recently, Japanese scientists have developed an organometallic catalyst that can help break down the amide bond and does not require high pressure and temperature. The catalyst is a complex ruthenium compound with organic (bipyridine) ligands.
The amide bond can be broken by hydrogenation (hydrogen addition). In a new catalyst, the ruthenium ion, surrounded by a lump of ligands, is able to hold the hydrogen molecule and then deliver it to the amide bond to initiate its decay. According to scientists, this catalyst can be used to recover materials from waste plastics. It can also be used in the manufacture of medicines.