What are bio-based polymers?

Bio-based polymers are materials produced (at least in part) from biomass, generated from renewable resources, such as plant waste and algae. This family of materials can be biodegradable (such as polylactic acid) or nondegradable (such as bio-polyethylene). As the world increasingly seeks alternatives to non-renewable feedstocks, bio-based polymers are set to become more widespread throughout the chemicals industry.

Why are bio-based polymers important?

Conventional polymer production requires the use of fossil fuels – finite resources that typically produce significant amounts of greenhouse gases (GHGs) during their production and use. Fossil-based products, such as plastics, are also dangerous persistent pollutants that can harm ecosystems and threaten the global food chain. Scientists have therefore been searching for more renewable, and less polluting, solutions to meet the world’s manufacturing needs.

Bio-based polymers are one such alternative. Many decompose (“biodegrade”), naturally when broken down by microorganisms – under aerobic or anaerobic conditions. This decomposition produces carbon dioxide (CO2), methane, and water, without giving off other toxic emissions.

How are bio-based polymers made?

There are two main methods. The first is direct production, also known as “biosynthesis”, in which algae, plants, and certain types of fungi synthesize bio-based polymers through enzyme activity. Polymers produced in this way include cellulose, hemicellulose, starch, inulin, and pectin. These polymers can then be extracted through chemical or mechanical processes.

The second method is the polymerization of bio-based monomers – taking simple compounds that occur in nature and linking them together through chemical reactions. This technique often uses the compound 1,3 Propanediol (PDO) as a chemical building block. Products made using this kind of polymer include composites, adhesives, laminates, coatings, moldings, aliphatic polyesters, and copolyesters.

What are the challenges with bio-based polymers?

Although bio-based polymers have many environmental upsides, there is still potential to improve their production efficiency and environmental impact. Modern agricultural methods, which are often used to produce the building blocks for polymerization, can themselves be highly polluting. Reducing the environmental impact of bio-polymers is, therefore, a high priority for the industry.

Scaling up the production of bio-based polymers is also a challenge, and there is a way to go before they can compete with the versatility and low cost of plastic. Since fossil-based options often remain the most cost-effective, significant investments and innovations are needed to reduce the cost of producing bio-based polymers.

What does the future hold for bio-based polymers?

With more and more organizations reducing their use of plastic and fossil-based materials, the size of the global bio-based polymer market is forecast to grow dramatically. In 2021, the market was worth USD 10.7 billion; by 2026, this is expected to reach USD 29.7 billion. With proper investment and support, bio-based polymers have the potential to revolutionize manufacturing processes all over the world.

There have also been several promising technological innovations in recent years. Labs are using plasticizers to make bio-based polymers less fragile, combining different polymers to deliver materials with a range of properties, and expanding compatibilizers to balance out polymer mixes. Scientists have also improved the hindrance and mechanical properties of these polymers by focusing on nanocomposites – minuscule polymer networks that can mimic the properties of conventional plastic with far greater success than before. These innovations will increase the usefulness of bio-based polymers in medicine, industry, agriculture, and beyond.

Learn about our CHAMPION project, which aims to replace conventional fossil-based materials with bio-based polymers. And you can browse Stahl’s full portfolio of products containing bio-based technologies here.