After being used for military purposes during the Civil War, coal was first used to generate electricity for homes and factories in the 1880s. As a fossil fuel, coal played an important role in the industrial revolution and also the industrialization that took place in the 1940s and 1970s. While our modern life is supported by electricity generated by coal, the pollutions that come with it must be addressed.
Technological Innovation is Usually a Good Tool to Solve a Problem
Through technological innovation, coal is gradually being replaced by hydrocarbons (oil and natural gas), nuclear power and renewable sources (solar, hydronic, wind, geothermal and biomass energy). The same transition is happening in the materials field. Plastics, as a material, is also transitioning from fossil-based to recycled and bio-based plastic.
Based on my experience in leading global research and innovation relating to sustainable materials, I've seen firsthand the misconceptions around bio-based material. To better understand the differences and nuances of these materials, it's important to first look at the terminology.
More and more “eco-friendly” plastics have been developed, and the terms bio-based, fossil-based, bioplastics, biodegradable and degradable appear in various media channels. While all these terms come with certain technical contexts, they're easy to misuse. It's not uncommon to see people holding inaccurate assumptions or perceptions of these terms.
Two common misconceptions are that bio-based plastics are biodegradable and fossil-based (petroleum-based) plastics are non-degradable. The truth is that 100% bio-based plastics could be non-biodegradable, while 100% fossil-based plastics can be biodegradable. There is no absolute correlation between the raw materials used to make plastics and their biodegradability. Instead, biodegradability is determined by the chemical structure of the material.
Bio-Based Materials and Fossil-Based Materials
Bio-based materials are materials wholly or partly derived from biomass. For example, corn, sugarcane wastes and cellulose are common bio sources for bio-based plastics. The fact is bio sources are renewable, which means theoretically we can generate continuously without harming the environment. However, the underlying assumption is the plants are grown in a proper system that does not generate negative impacts on humans, such as competing with our food sources and harming the environment (e.g., deforestation).
Currently, not all types of plastics can achieve 100% bio-based status. Achieving higher bio-based content is the goal. There is only a fixed amount of fossil fuels on our planet, and with an aim to slow down the usage of fossil fuels (mainly crude oil), a considerable amount of R&D efforts have been put into renewable energy, recycling technology and alternative raw material sources in the past decades.
Bio-based plastics are one example of an alternative raw material source where plastics are made from biomass instead of fossil-based materials. Thanks to the efforts invested in R&D, bio-based plastics, in general, come with similar properties and performance to fossil-based plastics.
Biodegradability and Degradability
“Biodegradable” means that, with the help of microorganisms, a material can be broken down into natural elements (such as water, biomass, compost, etc.). It is a chemical process that turns bio-based plastics into natural substances. However, the speed and the efficiency of the process depend on the conditions and environments where the biodegradable process takes place.
There are a few international standards in determining biodegradability. For example, packaging material can be claimed as biodegradable if it can be biodegraded at least 90% within 12 months. A responsible company should declare clearly which biodegradable standard they are using.
“Degradable” means a material disintegrates over time when exposed to sunlight, moisture and/or heat. It does not require the material to turn into biomasses. By introducing an additive to plastics, the plastics can be degraded. However, it is not ideal, as the plastics will turn into very small pieces called microplastics, which will create an even bigger problem if not controlled. Collecting, sorting and recycling is a better way to handle it.
Bioplastics can also be confusing. Bioplastic is a general term that includes bio-based non-biodegradable, bio-based biodegradable and fossil-based biodegradable plastics. In another word, only fossil-based non-biodegradable materials are excluded from this terminology.
The key takeaway is bioplastics and bio-based plastics are not necessarily biodegradable.
Why You Should Know
It is a big and yet common misunderstanding that bio-based material should also be biodegradable. Another common misconception is everything that can be degraded is good for the environment.
We all understand bio-based materials help reduce the use of non-renewable sources, and biodegradable materials help ease the land and marine pollution problems. If people can have a clearer understanding of the technical aspects of these terms, we can enhance communications and, eventually, help better circulate the correct information and ultimately make the right decisions, including policymaking.
Natalia Scherbakoff is a member of Forbes Technology Council. Get more insights from Scherbakoff’s thought leadership by reading her posts published on Forbes.com.