In the last decade, interest in biodegradable plastics and biodegradable packaging has skyrocketed. Indeed, when more than 67 million kilos of packaging waste is generated in the EU alone, and a substantial amount turns into everyday waste. Food packaging, in particular, is one of the most common sources of packaging waste in the UK.
Biodegradable packaging – sometimes referred to more generally as ‘green packaging’ – has often had an exceptionally positive reception among the general public. This is not surprising, because, more than ever, we need to try and reduce our carbon footprint as much as possible. However, there is still much misinformation around the topic. In this post, we aim to explain the biggest advantages and disadvantages around biodegradable shrink wrap in particular.
What is Biodegradable Packaging?
According to the ISO (the International Organization for Standardization), biodegradation of plastic waste refers to degradation caused by biological activity, such as enzymatic action, leading to a significant change in the material’s chemical structure. Something has ‘biodegraded’ when about 90% of the maximum level of biodegradation has been reached.
Biodegradability is an end of life option that allows one to harness the power of microorganisms present in the selected disposal environment to completely remove biodegradable plastic products from the environmental compartment in a timely, safe and efficient manner. Biodegradation that can take place in water is sometimes referred to as hydro-degradable material.
Typically, biodegradation has to take place as a result of microorganisms found in either water or carbon dioxide. The nature of the environment, the degree of microbial utilisation (biodegradation), and the time frame in which biodegradation occurs are specified in an ASTM (formerly the American Society for Testing and Materials) standard. When we commonly refer to biodegradable plastics, we tend to be talking about things that biodegrade in a matter of years – some petroleum-based plastics technically will biodegrade over much longer time frames but are hardly environmentally friendly.
The most common types of biodegradable plastics are PLA and PCL – polylactic acid and polycaprolactone respectively. PCL’s low melting point (60 degrees Celsius) makes it unsuitable as a shrink wrap material. By contrast, PLA is not only biodegradable but also a bio-based plastic, typically made from vegetables such as corn that are transformed to lactic acid before polymerisation. You can read more about the varieties of bioplastic in our past blog post.
What You Need to Know About PLA Packaging
As we have established, PLA is one of the more popular kinds of biodegradable shrink wrap. This means that we can significantly mitigate the environmental impact of said shrink wrap in the environment, something which adds value to any business’ offerings. To evaluate biodegradable shrink wrap, we’ll take PLA as an example and go through its supposed strengths and its weaknesses.
However, to biodegrade, PLA requires a laundry list of conditions to effectively break down, specifically a temperature of over 140 degrees, high humidity, plenty of oxygen and a 2/3 cocktail of organic substrate mixed alongside PLA. Collectively, these are absent in any scenario outside of industrial composting facilities. This means that, without proper disposal, PLA plastic will sit in landfills and will not degrade. Furthermore, the high costs of proper disposal can come as a big surprise to many businesses.
Secondly, PLA is a bio-based plastic. As PLA is produced from polylactic acid, which in turn is produced from vegetables like sugarcane or corn. This reduces one’s reliance on petroleum-based products, which makes PLA seem environmentally friendly.
However, as we’ve talked about before on resource minimisation, using bio-based plastics can give you a false sense of security. Limited resources that have to be spent producing bio-based PLA could be spent in the food production or water supply, and the tools used to convert vegetables into PLA still have a significant environmental footprint.
Thirdly, PLA is a compostable plastic. Compostable plastics are a new generation of plastics which are degradable through composting. They are generally derived from renewable raw materials like starch, cellulose, soy protein, or lactic acid. They are not hazardous in production and decompose back to carbon dioxide, water and biomass when composted. Counterintuitively, some compostable plastics may not be derived from renewable materials at all but instead derived from petroleum or made by bacteria through a process of microbial fermentation.
However, PLA is not an easily compostable plastic. Compostability requires a commercial composting facility, where higher temperatures can be achieved, and total composting is realised in 90 to 180 days. As such, unless you send your plastic to a dedicated composting facility, it is unlikely to compost. Indeed, recent investigations at Berkeley show that compostable plastics don’t even often end up composted. PLA plastic will last as long as any non-compostable alternative if not properly degraded, meaning your environmental footprint might be the same.
What About Oxo-Degradable Plastics?
There is a lot of talk in the industry in the last few years about the development of oxo-biodegradable, sometimes called oxo-degradable, plastics. Oxo-biodegradation proposes that, indeed, the plastic progresses from degradation to being entirely assimilated by the microbial populations in the disposal infrastructure, but this requires complete decomposition within a reasonably short period under customary methods of disposal.
Current technology in display shrink film offers only oxo-biodegradable material; unfortunately, there are no compostable resins available that would work in shrink wrap. Should any high-quality shrink film come to market, rest assured we would be the first to offer it.
Kempner is consistently at the forefront of sourcing the most technologically advanced films. From our polyolefin shrink wrap to our PVC shrink wrap film, we are known for the most sophisticated shrink films in the lowest thicknesses yet with unbeatable performance. However, at the moment, all current thinking concerns reuse and recycling as the best ways to minimise our carbon footprint. That’s why Kempner remains focussed on resource minimisation to reduce the environmental impact of our films.
If you are looking for shrink wrapping machinery or a shrink wrap provider for your business, get in touch, and we would be happy to provide you with our expertise. Call us at 020 8952 5262 or leave us a message in our enquiry box on the right-hand side of this webpage to get in touch.