January 23, 2009
The Promise of Bioplastics: Can They Save Packaging In Time to Save the Earth
by Eric Hartman, Product Ventures VP Technologies and Commercialization
Technically speaking, bioplastics are plastics manufactured using biopolymers, which are polymers that are present in or created by living organisms. These include polymers from renewable resources that can be further processed to create bioplastics.
Bioplastics can be derived from renewable biological resources such as corn, vegetable oils, soybeans, wood, grasses, or other natural feedstock. They are generally regarded as being more sustainable than those derived from fossil fuels as a carbon source and are believed to introduce less net new greenhouse gasses into the atmosphere if or when they degrade.
Unfortunately, the cultivation and production of bioplastic materials is not energy-neutral. In our current society, the energy used for the growing of raw materials to produce bioplastics and polymers, and the energy used in the conversion process to turn them into workable materials, is most often based on the consumption of fossil fuels. This non-renewably sourced energy is used to power farm machinery and irrigate crops. It is used for transporting crops to processing plants and also in the production of the fertilizers and pesticides necessary to derive acceptable yields from the crops. It is also used to extract the processable biomaterials from the biomass, and ultimately, to produce the bioplastic.
An economic shift
Our fossil fuel-based economy has been in place for well over a century. During that time, the economy has had the opportunity to develop a level of efficiency in the conversion process of fossil fuels to produce a wide variety of materials and energy products. Bioplastics, on the other hand—at least those which are being explored as substitutes for petroleum-based materials—are relatively new to the global scene.
One could argue that cellulose, one of the oldest plastics and itself a bioplastic, has had sufficient time in which to fulfill its potential for widespread use. Unfortunately, cellulose (like many newer bioplastics) has a limited range of functionality that restricts it to a narrow scope of applications. Fossil fuel-derived materials, on the other hand, have been the target of significant research efforts that have resulted in an ever-expanding array of polymeric entities and have been tailored to a wide variety of properties and uses. These non-sustainable materials have long since eclipsed cellulose in their versatility.
In order to completely replace petroleum-derived materials, bioplastics still have a long way to go, even though advances are being made in temperature resistance and other physical property improvements. For example, the sourcing of bioplastics has seen significant developments in recent days. From developments such as bio-derived polyethylene to developing bacteria or plants that directly produce certain plastic materials such as PHA, more research is focusing on and succeeding in developing options for new sourcing of bioplastics.
It has been noted that current bioplastic sourcing competes directly with food production, since the part of the plant that is consumed is also the same part that is used to produce the bioplastic or biopolymer. New research is focusing on the development of methodologies to that still allow the fruit or seed of the plant to be harvested for food production while utilizing the non-food portion (leaves, stalks, etc.) to be used as the source of the bioplastic material. Although these technologies are in their infancy and still must undergo a significant amount of development effort before they are commercially and economically viable, they are in the same position as petrochemical-based polymers were at the beginning of the 20th century.
Of course, one key issue here is that we don't have another hundred years to wait for bioplastics to become mainstream. Our need for more sustainable replacement of petrochemical-based materials is urgent, as is the need for reducing our dependence on the use of fossil fuels to drive our economy. Just as we must now invest in technologies for clean and alternative energy sources, so must we make the investment in the development of bioplastics.
We also need to develop the infrastructure to effectively manage end-of-life scenarios for bioplastics. Not all bioplastics are readily biodegradable. Like petroleum-based polymers sourced from finite materials, as long as the energy required to reprocess or recycle the material is less than that originally required for the production of the virgin material, it makes more sense to recycle and reprocess the biopolymer, rather than attempt to dispose of it through other means, such as composting or waste-to-energy conversion. For biopolymers that are easily biodegradable, the alternative is to allow them to undergo the degradation process and convert back to carbon dioxide, water, and biomass.
Currently, the use of biopolymers is in its infancy, but there is a need to change our mindset away from fossil fuelderived non-sustainable materials and to embrace and develop new materials and technologies that will allow our society to continue to grow and prosper. While bioplastics are not the only answer, they are one viable solution to the creation of a sustainable society that we need to nurture and develop further. The alternative route and the current mindset are not sustainable. Bioplastics are a critical technology that must be embraced to not only help save the planet for future generations, but to expand options to help us better manage resources and enjoy a healthier environment and economy today.
Eric Hartman is director of technology and development at Product Ventures, a creative agency for structural packaging innovation. With a background in Polymer Science and Engineering, and more than 25 years of packaging development and engineering experience, Eric has been instrumental in the development and implementation of innovative packaging solutions in many industries. He can be reached at 203-319-1119 or www.productventures.com.