An “alphabet soup” of less-familiar biopolymer materials with packaging uses is being heavily studied around the world, according to articles in the new Journal of Renewable Materials and recent entries in the JRM’s blog. This posting will mention just a couple examples:
One new biopolymer example uses plant-based sugars having five and six carbon atoms as its building blocks – a particularly “green” approach if the sugars are sourced from non-edible materials such as corn cobs, oat hulls, bagasse (sugarcane fiber), or even microalgae. The sugars can then be used produce to furan-2,5-dicarboxylic acid (FDCA) – which can then be used to polymerize polyethylene furanoate (PEF), a material that’s a potential recyclable, biobased alternative to PET.
PEF reportedly has better gas-barrier properties than PET, making it a good fit for bottling beverages, though the researcher-author of the JRM paper notes that more understanding is needed about its properties and behavior.
Other research efforts are focusing on a natural nylon, a “nylon-4 derivative”: poly(γ-glutamic acid) (abbreviated as PGGA or γ-PGA). PGGA is based on γ-glutamic acid, which can be synthesized by certain bacteria.
A paper from the first issue of the JRM describes various chemical modifications of PGGA. These could expand its applications beyond just specialized biomedical uses into mainstream packaging applications of more conventional biopolymers, like polylactic acid and polyhydroxyalkanoates. So in coming decades, we might expect unfamiliar polymer abbreviations like PGGA to become household names, as PLA and PHA are already becoming.
Mike Tolinski is the author of Plastics and Sustainability, published in 2012 by Wiley-Scrivener, and he is Contributing Editor for Plastics Engineering magazine of the Society of Plastics Engineers in the USA. His views have been shaped by his engineering, university, and journalism experience in the plastics and manufacturing industries over the past 23 years. You can follow Mike and be alerted on his blog updates via Twitter.