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Issue 03/2019

Highlights: Toys Injection Moulding Basics: Microplastics Mind the right terms Captured CO2

Basics Mind the right

Basics Mind the right terms Biodegradable vs. compostable vs. oxo-degradable plastics: A straightforward explanation As consumer demand for sustainable products grows, bioplastics —which can reduce our reliance on fossil fuels and decrease greenhouse gas emissions— will become more prevalent. Production of bioplastics is expected to grow by as much as 20% by 2022 [1], and as it does, consumer understanding of bioplastics will need to grow with it. A major source of confusion is the difference between three terms: Biodegradability, compostability and oxodegradability. Although these terms are often used interchangeably, they are not synonymous. Confusion regarding common bioplastics terminology such as these, especially where it concerns the disposal of bioplastic products, can have dire consequences. Companies need to understand the distinctions between each category in order to accurately and honestly market their products. And consumers need to understand these terms in order to make educated purchasing decisions and properly dispose of bioplastic products at the end of use. Understanding bioplastics: Biobased vs. biodegradable To understand these three terms (i.e., biodegradability, compostability and oxo-degradability), it is important first to clearly understand the definition of bioplastics [2]. Bioplastics refer to a large family of plastics which are sourced from biomass at the beginning of their life (biobased), metabolized into organic biomass at the end of their life (biodegradable), or both. Based on this, bioplastics can be broken down into three distinct classifications [3]: • Fully or partially biobased but NOT biodegradable. (e.g., biobased PET, biobased PE, Terratek® SC or Terratek® WC) • Fully or partially biobased AND biodegradable (e.g., PLA or starch blends such as Terratek® BD). • Biodegradable and petroleum-based (e.g., PCL). Biodegradable plastics are a relatively small subset of bioplastics which can be converted into water, carbon dioxide (CO2) and bio-mass over time with the help of micro-organisms — this process is called biodegradation. And because the biodegradability of a plastic lies within the chemical structure of the polymer —and not the source of the feedstock— biodegradable plastics can be either bio- or petroleum-based. Biodegradable vs. compostable vs. oxodegradable plastics Nearly every material will biodegrade, given enough time. But the length of the biodegradation process is highly dependent on environmental parameters such as humidity and temperature, which is why claiming that a plastic is “biodegradable” without any further context (i.e., in what timeframe and under what environmental conditions) is misleading to consumers. Reputable companies will often make more specific claims, primarily certifying that their bioplastics are compostable. Compostable plastics are a subset of biodegradable plastics, defined by the standard conditions and timeframe under which they will biodegrade. All compostable plastics are biodegradable, but not all biodegradable plastics would be considered compostable. Certified compostable: A more specific claim of biodegradability Compostable plastics are those plastics which have been tested and certified by a third party (e.g. BPI [4], DIN Certco, TÜV Austria etc.) to adhere to international standards such as ASTM D6400 (in the U.S.) or EN 13432 (in Europe) for biodegradation in an industrial composting facility environment. Materials certified according to ASTM D6400 or EN 13432 will disintegrate within 12 weeks and biodegrade at least 90% within 180 days in a municipal or industrial composting facility. Approximately 10% of solid material will be left at the end of the six-month-long process in the form of valuable compost, or biomass and water. These standards also ensure that the leftover compost will be free of toxins, so the compost will not cause harm when the facility sells it for gardening or agricultural applications. Unless otherwise denoted, certified compostable products must be disposed of in a designated municipal composting facility, not at home. Many certified compostable materials require the higher temperatures of industrial settings to biodegrade quickly enough, or in some cases at all. Other than in many countries (in Europe e.g. Germany, Italy, France, Sweden, The Netherlands etc.) few areas in the USA have curbside collection for industrial composting, which is why certified compostable products are best utilized in closed systems such as amusement parks, stadiums and schools, where compostable and organic waste is carefully monitored and controlled to ensure proper disposal in an industrial composting facility. San Francisco International Airport [5] and Safeco Field in Seattle [6] are two good examples of organizations using composting as a means of reducing their carbon footprint and diverting organic waste from landfills. Find more info on the differences in different countries in bM 05/2018. A quick note on oxo-degradable plastics While often confused with biodegradable plastics, oxo-degradables are a category unto themselves. They are neither a bioplastic nor a biodegradable plastic, but rather a conventional plastic mixed with an additive in order to imitate biodegradation. Oxo-degradable plastics 54 bioplastics MAGAZINE [03/19] Vol. 14

By: Kevin Ireland Communications Manager Green Dot Bioplastics Emporia, Kansas, USA COMPEO quickly fragment into smaller and smaller pieces, called microplastics, but don’t break down at the molecular or polymer level like biodegradable and compostable plastics. The resulting microplastics are left in the environment indefinitely until they maybe eventually fully break down. A scientifically backed evidence for “bio”degradation was not presented until today. The importance of clearly and accurately labeling plastic products As bioplastics continue to gain market share in the coming years, being clear about the environmental benefits in product and material marketing is imperative. Looking to the U.S. Federal Trade Commission’s (FTC) Green Guides [7] is a good place to start. The Green Guides outline best practices for clearly labeling and marketing green products to ensure the expectations of the consumer align. Not only will transparency allow consumers to make smarter purchasing decisions, but it will ensure bioplastics are disposed of through the proper channels. Ultimately, better end-of-life disposal of bioplastics strengthens their environmental value proposition of diverting organic waste from landfills, reducing greenhouse gas emissions and ensuring the sustainable consumption of resources. For further reading we also suggest previous articles published in bioplastics MAGAZINE [8, 9, and 10]. They are available for download at en/miscellaneous/downloads.php Leading compounding technology for heat- and shear-sensitive plastics References [1] [2] [3] Material-Koordinatensystem_eng_2015_150109-1.jpg [4] [5] [6] [7] [8] Narayan, R.: Biodegradability - Sorting through Facts and Claims; bioplastics MAGAZINE 01/2009 [9] Narayan, R.: Misleading Claims and Misuse of Standards Continues to Proliferate in the Bioplastics Industry; bioplastics MAGAZINE 01/2010 [10] Ißbrücker, C.: Can Additives make conventional plastics biodegradable? bioplastics MAGAZINE 01/2017 Uniquely efficient. Incredibly versatile. Amazingly flexible. With its new COMPEO Kneader series, BUSS continues to offer continuous compounding solutions that set the standard for heat- and shear-sensitive applications, in all industries, including for biopolymers. • Moderate, uniform shear rates • Extremely low temperature profile • Efficient injection of liquid components • Precise temperature control • High filler loadings bioplastics MAGAZINE [03/19] Vol. 14 55

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