INNOVATION: Bioplastic derived from “poo molecule”.

01. April 2019 | Material | via Lunduniversity.lu.se

Ping Wang (Credit: Theo Hagman-Rogowski)

According to an article on Lunduniversity.lu.se almost all plastic is made from crude oil, and plastic production currently accounts for 4-6% of global oil consumption. The development of renewable bioplastics is progressing, but relatively few are actually being used.

A strong candidate among bioplastics is polyethylene furanoate (PEF). Instead of oil, PEF contains the hydrocarbon, furan, which can be extracted from maize, wood and certain types of grain. The main market for PEF is packaging. Experiments have shown that PEF is superior to standard polyethylene terephthalate (PET) in protecting against oxygen, carbon dioxide and water, which gives products enclosed in plastic greater durability.

The success of PEF made researchers at Lund University interested in other renewable materials that could potentially be used for plastic production. Chemical engineering doctoral student Ping Wang has produced a plastic based on indole, a heavier hydrocarbon molecule than furan, that is present in human faeces and smells accordingly. The compound is also found in lower concentrations in certain flowering plants and has a more agreeable aroma. This effect is due to our sense of smell decoding the aroma differently depending on the amount and combination.

The research team is thought to be the only one researching indole polyesters, and their results are promising. A regular PET bottle’s glass-liquid transition temperature – when the material softens and deforms – is 70 degrees. The most successful PEF experiments withstand about 86 degrees. However, one of Ping Wang’s indole plastics is stable up to 99 degrees.