Q. What are bioplastics?
Bioplastics are biodegradable plastic materials that are made using renewable resources including vegetable oil, corn starch, cellulose, wood and derivatives of these resources. Bioplastics may not always be entirely made of these products, and are sometimes made of a composite of renewable resources and some petrochemical resources. However, bioplastics are biodegradable and must contain renewable resources.
Q. How are bioplastics being used in the packaging industry?
In general terms there is increasing interest in renewable resources in Australia. Australia is catching up to the UK in this respect, where renewable resources have been a part of public consideration for some time. Bioplastic materials are used widely in Europe for two primary reasons, firstly, because of increasing public interest in sustainable resources, and secondly, because of the limited space in Europe for waste disposal. Just recently Australia manufacturers that traditionally use petroleum based plastics have started to develop their awareness of renewable resources. There are also marketing advantages to using bioplastics and biodegradable packaging.
Q. What can manufacturers gain from using bioplastics?
The main benefit for manufacturers using bioplastics is the reduction of their overall environmental footprint. Bioplastics have a lower environmental footprint than traditional plastic packaging and can be disposed of through composting. There is little commercial composting infrastructure available at present in Australia, but it is starting to grow. While there are little financial benefits for the packager of the goods at this stage, environmental benefits are growing increasingly important. At this stage the total energy used in the manufacture of bioplastic packaging material is very similar to traditional plastic packaging. If a manufacturer was to make a bag or a thermo-formed blister pack with conventional plastic and bioplastic, the process is much the same, and there would be no benefit, nor disadvantage in the processing stages. However, manufacturers must consider the entire life cycle of the material, from producing the polymer, through to processing and, finally, the disposal of the product. If manufacturers look at the total lifecycle of a bioplastics product, and assume it is composted, the overall contribution to greenhouse gases and the overall environmental footprint is lower.
Q. What classifies as biodegradable?
There are currently standards in place in Australia, North America, Europe, and Japan. The most common standard is EN13432, which is a European standard, and that is for compostable packaging materials. The Australian standard in AS 4736-2006 Biodegradable plastics — Biodegradable plastics suitable for composting and other microbial treatment sets. To meet the requirements of this standard the materials must be biodegradable. To be biodegradable the material must biodegrade up to a minimum of 90% compared to pure cellulose, and that is determined by measuring the Carbon Dioxide given off from a material as it biodegrades. The amount of Carbon Dioxide is compared to a minimum theoretical amount of Carbon Dioxide that can come off a known mass of material. The product must also be compostable, so it must disintegrate within a certain amount of time, and must be non-toxic so that the biodegradation process has no effect on animal or plant growth. To receive certification for the Australian standard all of these requirements must be met. The Australasian Bioplastics Association supports the adoption of international bioplastics standards across the world.
Q. What are the challenges in using bioplastics?
One of the challenges in using this material is sorting out the wheat from the chaff, so to speak. Materials that are said to be biodegradable are sometimes not, and simply disintegrate rather than compost. It is sometimes difficult for a manufacturer or packager to know what is the real thing. One of the ways to do determine the viability of a material is to refer to the Australian standard, and label to those standards. In other parts of the world there are standards that are instantly recognised within the industry and the general public. The Australasian Bioplastics Association is currently in the process of implementing that infrastructure in Australia, and developing a standard that can be recognised by consumers and manufacturers alike. Many applications that conventional plastics are used for can be functionally serviced by bioplastics technology already. Just as manufacturers use a combination of conventional plastics, users can use composites of bioplastics when seeking certain properties from the products. The big hurdle for manufacturers has typically been the higher cost of implementing some bioplastic materials into their packaging, but that gap is narrowing. For example, polylactic acid (PLA) polymers are being used to bottle mineral water. PLA has very similar properties to polyethylene terephthalate (PET) plastic. In the past PLA was a lot more expensive than PET, but that gap has significantly narrowed. Bioplastic technology will only continue become less expensive than the traditional plastics.
Q. What steps should manufacturers take before implementing bioplastics packaging?
The Australasian Bioplastics Association exists to be a point of contact for industry to come to, so we would suggest that manufacturers contact the association. The association’s membership is comprised of the main participants of bioplastics in Australia and can provide manufacturers with all of the information required.
Key contact:
Australasian Bioplastics Association
warwickh@plastral.com.au
www.plastral.com.au
Add a comment