A more sustainable product, bioplastics reduce the use of non-renewable, oil-based resources, which are increasingly scarce and unstable in price. Bioplastics also reduce greenhouse gas generation in the plastics industry. By incorporating bioplastics to offset the use of fossil fuel-based materials in the industry, it makes finished products made with bioplastics more valuable to conscientious consumers in the new plastics economy. Products made with bioplastics may meet unique requirements for combinations of recyclability and biodegradability in a variety of environments such as soil, landfill and home composting. Incorporating biobased options helps us achieve greater environmental sustainability in the new plastics economy also helping companies meet corporate objectives and environmental policies.
WHAT IS A BIOPLASTIC?
A bioplastic is a plastic that is made partly or wholly from materials derived from biological sources such as sugar cane, potato starch or the cellulose from trees, straw and cotton and wheat. Bioplastics are often designed so that they biodegrade or compost, aided by fungi, bacteria and enzymes. Bioplastics can generally be directly substituted for their oil-based equivalent. They can also be made to be chemically identical to the standard industrial plastics.
BIOBASED, BIODEGRADABLE AND COMPOSTABLE: WHAT IS THE DIFFERENCE?
Biobased is defined as commercial or industrial products (other than food or feed) that are composed, in whole or in significant part, of biological products or renewable agricultural or forestry materials. Biobased content is determined by the ASTM D6866 testing method. This method, similar to radiocarbon dating, compares how much “new” or organic carbon (biological-based as defined above) is in a material compared to the amount of “old” or fossil fuel-based carbon it contains.
Biodegradation occurs when materials are broken down by bacteria, fungi, or other biological means. Composting requires biodegradation in order for organic matter to decompose and be turned into fertilizer and soil conditioners. Biodegradation and decomposition are processes that are a part of composting. Biodegradation can occur without composting, but composting cannot occur without biodegradation! Biodegradation is a process, not an end result.
Biodegradation is not the same as composting. Composting requires high heat conditions (50-700 C), usually in an industrial facility, for organic matter to decompose and be turned into fertilizer and soil conditioners. To claim compostability, a material must first disintegrate, and then biodegrade by 90% within 180 days. It must also pass tests for low levels of plant toxicity and heavy metal content. Meeting all of these standards leads to meeting ASTM D6400 compostability standards.
TWO TYPES OF BIODEGRADATION
Anaerobic digestion occurs when microorganisms break down material in the absence of oxygen. It is used in industrial processes to manage waste or to produce fuels. Anaerobic digestion occurs naturally in some soils as well as in landfills. Methane (CH4) and carbon dioxide (CO2), both greenhouse gases, are two end products of this process.
Aerobic digestion occurs when material is broken down in the presence of oxygen. It has traditionally been used as a sewage treatment process, but recent technology allows for the aerobic treatment of food, cardboard, and plant waste in industrial compost facilities and water environments. Water vapor, carbon dioxide, and ammonia (NH4) are end products of this process.
BEWARE OF “GREENWASHING” OXO-BIODEGRADABLE PRODUCTS
Oxo-biodegradable plastic is made by blending a pro-degradent additive into a plastic during the extrusion process. This additive is a catalyst which speeds up plastic degradation in the environment, leaving residue and small fragments. However, there is a considerable risk that these fragmented plastics will not fully biodegrade and the subsequent risk of an accelerated and accumulating amount of harmful microplastics in the environment. The most desirable result for waste plastic products is that they completely biodegrade.
Beware of “biodegradable” claims, and remember to make sure when purchasing biodegradable products that they meet specified BPI-approved, ASTM D6400 or D6868 standards.
Please keep in mind that your company is responsible for any claims that it makes regarding the functional and environmental performance of products or polymers that are biobased. Please consult your sustainability, regulatory and legal departments before making such claims. Proper certification also promotes proper use, disposal and reuse of plastic products.
We can help you develop a certification roadmap that includes the testing protocols that can lead to your specific product being promoted and/or certified as biobased, compostable or biodegradable. Feel free to contact us at New Composite Partners for more information.