Plantics-GX: a biodegradable and cost-effective thermoset plastic that is 100% plant-based.

We recount here the story of the discovery and invention of a family of thermoset resins that are fully biodegradable and plant-based. The resin is prepared by polymerising glycerol, the simplest trialcohol, with citric acid, the simplest abundantly available triacid. Mixing these two chemicals at moderate temperatures begins a multi-step esterification that results in a network-like resin foam. The hardness, brittleness, and toughness of this resin can be controlled by changing the alcohol : acid ratio, the temperature, and the presence of additives. Remarkably, this resin is fully biodegradable, breaking down to its molecular components in water. The degradation period can be varied from a few days to a few months, depending on the degree of polymerisation. We have prepared over 800 different formulations of this new material, which is now being produced on the ton scale by Plantics BV in The Netherlands under the trade names Glycix and Plantics-GX. This resin is made from inexpensive and widely available starting materials. It is 100% biobased, non-toxic and biodegradable. Thus, it has the potential to replace petro-based thermoset polymers and foams in a variety of real-life applications.