Renewable Monomers for Biodegradable Polyester Synthesis

As mentioned before, there are a few biodegradable polyesters which were historically obtained from renewable sources as their production concerns fermentation or microbial processes from vegetable raw material (i.e., PLA, PHA and more recently polyhydroxyfattyacid). Moreover, in the last 5 years an increasing interest in renewable raw material for polymer synthesis has been developed, not only for biodegradable polyester production but also for nonbiodegradable polymers such as polyethylene or PET. 

With regards to biodegradable polyester production, the use of renewable monomers can be of particular interest as not only can the final products be biodegraded, hence avoiding plastic accumulation in landfills, but also the biodegradation products (usually CO2 and water) are used by plants to produce the renewable monomers. As can be deduced, this cradle-to-grave cycle can significantly reduce the carbon footprint due to plastic production. 

In recent years, a breakthrough towards renewable monomer production has been possible with the help of genetic science, which can manipulate microorganisms to produce specific molecules from vegetable raw materials. 

The main monomers for the most common biodegradable polyester production, which can now be obtained from renewable resources are succinic acid, 1,4-butanediol, 1,2-ethanediol, sebacic acid and azelaic acid. 

So far, wholly renewable biodegradable polyesters belong only to the aliphatic family, but efforts are being made to obtain aromatic dicarboxylic acids from renewable resources in order to fill this gap, as demonstrated by the research achievements involving aliphatic-aromatic copolyesters based on furandicarboxylic acid [59-61]. 

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