Bioplastics are an emerging and growing trend in the packaging industry. But before these plastics are discussed in more detail one needs to know what bioplastics are. Bioplastics are plastics that are based on raw materials from renewable sources and that they can be recycled through composting. Most of us have come in contact with a bioplastic in the form of the liner bag for the kitchen garbage that goes into the green bin for curb-side collection. The first time I came in contact with this type of plastic I realized that it felt different from the known plastics. This is quite understandable since bioplastics are made from a different type of polymer than the plastics that are based on petrochemicals.
Bioplastics are made from starch which is derived from potato peels and corn husk and from polylactic acid (PLA), which is obtained from the same type of raw material source. The raw materials for bioplastics are not specifically grown for this purpose, but rather the leftovers from corn and potato processing are used to manufacture these new plastic materials. This means that no agricultural area is taken out of the food chain to grow the raw material base for bioplastics.
Starch and polylactic acid can be mixed and together with a now available biodegradable polyethylene can form a variety of foils and packaging items. Manufacturers of these materials are striving to get the products certified for use in industrial composting facilities. In order to achieve this certification the product needs to fully decompose within 90 days in an industrial composting facility. This means the bioplastic is really decomposing and not breaking up into smaller particles, like oxo-degradable plastics, which are not visible anymore, but the plastic is still there; only the particles are quite small and therefore not visible.
During the InterPack trade show in May 2011 there was a special exhibition in regards to bioplastics. Manufacturers of the resins used for manufacturing bioplastic-based materials were present, as well as distributors and manufacturers of items made from these materials. This starts with the compostable bag for kitchen garbage and the compostable shopping bag. A compostable shopping bag can be used many times and does not rot as soon as it comes in contact with food and moisture. The decomposing only takes place in the composting facility.
One company showed many different items that were made from bioplastics and they include clear or coloured drinking cups, cutlery, food plates and small boxes for transporting take-out food. These items looked like the ones based on petrochemicals, but in contrast to the current products they are fully compostable. One company handed out candy bags that were also made from a compostable bag, but the bag looked and felt like one made from petrochemicals. A few multinational plastic and ink manufacturing companies were behind this product to showcase what is already possible today.
A large multinational dairy company announced that they will be using yoghurt cups made from bioplasctic as they handed out filled yoghurt cups together with a compostable spoon. Let’s see how long it will take for these products to hit the Canadian market.
Bioplastics are manufactured by companies in Germany and Asia. Large and well-known chemical companies are going into the manufacturing of bioplastics and they presented their line of products at the Interpack trade show.
Everyday plastic products based on bioplastics will start to replace their petrochemical cousins. Soon one will be able to throw the yoghurt cup and other items made from bioplastics into the green bin, knowing very well that they will decompose and transform into soil that can be used in anyone’s garden. Plastic products will lose their stigma of being wasteful once they are replaced by biodegradeable ones.
The only difficulty at this point in time is, that the consumer needs to pay very good attention to what type of plastic he or she holds in his/her hands and puts them in the proper recycling bin. Bioplastics should be thrown into the green bin and other plastics into the blue bin. When more bioplastic-based items come onto the market it might be a good idea to have manufacturers put a well identifiable logo onto bioplastics so the consumer knows that this item can be thrown into the green bin.