How plastics made from plants could be the solution to the world’s waste problem

Plastics are incredibly useful materials with extremely diverse properties.

Bottles, tubes, boxes, medical devices, the list is endless.

A fundamental part of this issue is that non-sustainable, single-use plastics account for up to 40% of global plastic production. The vast majority of these plastics have low recycling rates and do not biodegrade in an acceptable time. Polypropylene can take millennia to break down properly.

Worse still, if these plastics find their way into the marine environment, the motion of the sea along with sunlight can cause the plastics to fracture into small particulates called “microplastics”.

The presence of macro and microplastics in our oceans has been shown to have a detrimental effect on marine life.

But while it’s known that plastics can be a problem for the environment, what isn’t often known is that the persistence of plastics in the environment is actually closely linked to how they are made.

The overwhelming majority of plastics are made using oil-based materials, meaning that, by their chemical nature, many plastics have no oxygen content. This makes them very hydrophobic (water hating) and, as such, it is very difficult for common bacteria or enzymes to break them down.

Sustainable bio-based material can be waste crops, waste wood, waste food or any waste biological matter.

Most importantly, these natural, bio-based materials can easily be broken down into smaller chemical building blocks which in turn, can be used to make other useful chemicals, including plastics.

Green Chemistry Centre of Excellence at the University of York, has been working to create a new generation of bio-based polyesters. The resulting materials are entirely plant based, recyclable and fully biodegradable.

By using bio-based materials to make bio-based plastics, the oxygen content is kept in the material. The hope is that by having a high oxygen content, the bio-based plastics will have high, but controlled biodegradability. This means that the bio-based plastic can totally and safely break down into benign starting materials.

Plastics are a fundamental part of modern society and they are here to stay. Ultimately, society has to move away from oil-based products towards sustainable bio-based alternatives.

Regardless of whether a plastic is oil-based or plant-based, the biggest impact you can have on the life cycle of a plastic product is to reuse and recycle it.