Replacing fossil-based plastics with bio-based and biodegradable plastics: it’s complicated, but it can be done!

This is the sixth blog in a blog series on the Circular & Climate-neutral research programme. This programme (KB-34) focuses on research that contributes to circular and climate-positive production systems for food and non-food products.

Fighting the fossil-based blanket. That’s the combative name for the research we’re conducting as part of the Knowledge Base (KB-34) research programme Circular & Climate-neutral Society. In collaboration with a variety of WUR research associates and disciplines, we’re working at three different levels to show how new polymers can tackle the problem of pollution caused by fossil-based plastics. We’re looking at the technological development of new plant-based materials, and predicting the effect of these and other plastics on pollution and on the accumulation of microplastics. Finally, we’re using an economic model to calculate the impact on the global economy. Replacing fossil-based plastics with bio-based and biodegradable plastics is complicated, but it can be done!

We’re using a multidisciplinary team to investigate how best to use plastic for particular products in a way that avoids dependence on fossil-based raw materials and leaves no trace afterwards. For hard plastics, for example, we now have good bio-based alternatives, with the added advantage that the products made from them – such as toys and kitchen appliances – generally don’t end up in the natural environment when they come to the end of their lives, making them fairly easy to reuse.

Selection tool for circular alternatives

Thinking about this led Evelien Maaskant and me to the idea of developing a selection tool for circular alternatives to fossil-based plastics. But under the traditional design method, product developers emphatically prioritise functionality over anything else, and that isn’t conducive to the selection of bio-based and biodegradable alternatives. So in addition to the selection tool, we’re also proposing a different design strategy: rather than functionality, the starting point for choosing raw materials should be a product’s end-of-life.

Fighting the fossil-based blanket

This design vision, along with the selection tool, is underpinning the launch of our new multidisciplinary research: Fighting the fossil-based blanket. We’re working at three levels to develop and drive substitution with bio-based plastics:

1. New plastics based on plant technology

We’re working with Wageningen Plant Research to conduct research into the technology of plants, which are in effect small factories that make new molecules, with a wide variety of different properties. The range of different materials with specific properties is theoretically many times greater than we can currently imagine, assuming we can make use of the advanced technology found in plants. We see potential here to create bio-based building blocks for new high-barrier biodegradable plastics (to preserve food for longer) and elastic, rubbery plastics for products such as tyres, which according to RIVM are the major contributors to microplastics and for which there are as yet no biodegradable alternatives.
Initial results are promising. An article on our development of new plastics is currently up for review with a renowned academic journal.

2. Model for accumulation of traditional and new plastics in the environment

Other scientific studies are telling us more and more about the impact of microplastics: where they end up, the implications for nature and for humans, how quickly or slowly they break down and under what conditions. Within the project, Wageningen Food & Biobased Research is developing a model that can extrapolate the effect of specific types of plastic on the formation and accumulation of microplastics in the environment. This will enable us to demonstrate at the product level what replacing plastic X with Y (or Z) would mean for plastic pollution in the environment. This will in turn encourage the preferred option of back engineering, with design based on the end-of-life perspective.

3. Modular Applied General Equilibrium Tool for traditional and new plastics

As part of this project, we’re working with Wageningen Economic Research on extending the MAGNET model. This model sheds light on the impact on the global economy of replacing fossil-based plastics with bio-based plastics. It considers a variety of issues, from land use to oil extraction, water needs, and transport. Using MAGNET, we can show the economic impact of producing plastic X, Y or Z. This will enable manufacturers to make better choices and to understand what the switch to a different (possibly bio-based) plastic entails in financial terms.

Stimulate and accelerate

We believe that these three micro, macro and mega-level studies will stimulate and accelerate the transition from fossil-based to bio-based plastics within the next few years. This will help create a world in which we carefully scrutinise our use of plastic: where is it really needed and where can we do without it? Wherever the use of plastic is unavoidable, our multidisciplinary WUR approach is encouraging the use of bio-based plastics and effective recycling, while also reducing and preventing the accumulation of microplastics in the environment. This transition is complicated, but certainly not impossible. Fighting the fossil-based blanket? It really is achievable!