​ Making new plastics that are easier to recycle and more profitable

 

One of the basic problems of recycling plastics is that when they are recycled often they weaken with each reuse and sometimes recyclers have no idea how many times the plastic coming in has been recycled. Most plastics contain carbon hydrogen bonds which are some of the strongest chemical bonds found in nature and this heist ability makes it difficult to turn natural products into other chemicals and is a challenge to recycling commodity plastics. By modifying the carbon hydrogen bonds are in common polymers the lifespan of these polymers could be extended beyond a single use. The Leibfarth group how developed a system by selectively pulling hydrogen atoms from a polyolefin so that they can extend the life of a single use plastic into a high-value plastic known as an ionomer. Most recycle plastic is down cycled into lower quality products like carpets or polyester clothing and this still ends up in landfills, but if the chemistry can be repeatedly applied to polymers it will help them be recycled over and over again without weakening. Using a newly identified reagent they can strip hydrogen atoms off various different medicinal compounds and polymers and the UNC chemists were able to make new bonds in place of previously unreactive bonds.

 

Timothy J. Fazekas et al.; "Diversification of aliphatic C–H bonds in small molecules and polyolefins through radical chain transfer"; Science; 3 Feb 2022

Jon Gardiner/ University of North Carolina Chapel Hill



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