What are bioplastics and what are they used for?
The term bioplastics is composed of the two words bio and plastics – two conflicting terms for many people. Nevertheless, plastics can also be biological. Since the term is not sufficiently legally protected, there are different definitions. For some people, bioplastics are plastics made of renewable resources. For other people, bioplastics are all biodegradable plastics (including petroleum-based). Our bioplastics are both biodegradable and made of renewable resources. Most of our plastic products consist of the bioplastic polylactic acid (PLA) which is based on corn starch. Only our biodegradable plastic bags are made of Mater-Bi®, a bioplastic that does not only contain corn starch but also plant oil (no palm oil!). Further information about bioplastics can be found in our infofolder for bioplastics, the Indeo Journey and in our Mater-Bi® info PDF.
Bioplastics are an environmentally friendly alternative to petroleum-based plastics such as PP (polypropylene) and PS (polystyrene) and possess comparable characteristics. They are transparent and can be processed easily into various commodities, for example into cups, bowls, and bottles. These commodities belong to the most important sales market for bioplastics: the packaging industry, in particular the one for food. Here, bioplastics have a great advantage over conventional plastics because they can be disposed with food left-overs. The legal framework for the disposal is regulated in the German Packaging Ordinance (VerpackV) and in the Biowaste Ordinance (BioAbfV).
Until now, only 0,05% of the industrial starch production is used for bioplastics. This means that only a very small amount of petroleum-based plastics is substituted by biological plastics so far. According to different researches (amongst others „Global Bioplastic Market Forecast to 2020“, 2016 & „Marktstudie Biokunststoffe“ von Ceresana, 2014), bioplastics still have a huge market and growth potential because technical progress and increasing production capacities enhance their competitiveness against petroleum-based plastics. It is expected that the amount of bioplastics will continue to increase within the next years and replace old plastics.
From corn plants to cups and bowls made of bioplastic
Maize (zea mays), better known as corn, is an annual summer plant and belongs to the family of sweet grasses. It originally comes from Mexico but by now, it blooms from July to September in many parts of the world. In Germany, the farmers also plant corn during the summer months. The corn plants are 1 to 3 meters in height and bear piston-like fruit bunches with corn grains, which appear in different colours, depending on the species.
Just like every plant, maize performs photosynthesis. By the aid of the sunlight, it converts absorbed CO2 and water into glucose and oxygen. The non-required sugar is stored in the form of starch. This corn starch is relevant for is because it forms the raw material for the production of bioplastics.
Between September and October, the farmers harvest the corn cobs with field choppers. It is important to note that this corn is solely cultivated for industrial use and is not suitable for human consumption. After the harvest, the corn cobs are brought into so-called wet mills where the grains are processed into corn starch. In the following, we explain the necessary steps to convert corn starch into sustainable greenbox PLA cups and bowls.
Production steps for bioplastic products:
The corn starch is fermented into lactic acid by the aid of lactobacilli. This lactic acid is then transformed into long-chain carbon polymers (polylactic acid) by polymerization.
The polylactic acid (PLA) is molded into small plastic pellets which are then used to produce many different objects. In our case, the plastic pellets are used to produce bioplastic foil. Subsequently, this foil is used to produce PLA cups and bowls. It runs through different machines and is shaped into objects by the aid of forms, die cutters, and impact of heat.
Ready to go! The greenbox PLA cups and bowls are ready for transport and shipping and cannot wait for their application in your company.
Sustainability: No waste of non-renewable resources
Bioplastics consist of a renewable herbal resource (corn) and does not contribute to the waste of non-renewable resources such as petroleum. The corn used for the starch production is not intended for human consumption; it is specifically cultivated for industrial use. Only 0,05% of the global starch production is used for the manufacturing of bioplastics. Therefore, the cultivation has no impact on the food supply of humans and animals. As a matter of course, the corn used for bioplastics also requires cultivation areas. But only 1.500 hectare of sustainably managed areas in Europe and in the USA are used to plant corn. For comparison: Just the state Mecklenburg-West Pomerania has 1,36 million hectare of utilized agricultural area. If the amount of bioplastics continues to increase, the farmers require larger cultivation areas. For this reason, it is important to also use other agricultural waste for the starch production as well, for example cellulose from maize straw and sorghum.
According to studies of our suppliers, bioplastics such as polylactic acid (PLA) have an advantage over conventional plastics in terms of production. In contrast to petroleum-based plastics (PS & PET), the production of PLA causes 60% less CO<sub>2</sub> emission and wastes 50% less non-renewable energies. In „cradle to cradle“ researches, it also has advantages in terms of the greenhouse effect, the conservation of resources as well as the overall environmental balance. Here, it must be kept in mind that studies may differ, depending on different calculation factors for the overall environmental balance.
Polylactic acid is a biodegradable and compostable bioplastic. According to EN/DIN 13432, the bioplastic decomposes up to 90% into its organic substances within 90 days in an industrial composting facility. Due to different factors, the decomposition in open nature generally takes longer than in a composting facility. But no toxic residual materials such as chlorine-hydrocarbon compounds or other inorganic substances remain after the product’s decomposition. In contrast, the decomposition of petroleum-based plastics may take centuries or millenniums. Even then tiny, possibly toxic, micro particles remain and are eaten by animals and humans. In the ocean, the micro plastic particles even absorb poisons from the water. In open nature, plastics may also release toxic substances and affect the fertility of the soil. For this reason, it is important to replace petroleum-based plastics with sustainable bioplastics.
Special characteristics of bioplastics (PLA & Mater-Bi®)
• High stability
• Free from BPA and other harmful substances
• Consist of 100% herbal raw materials
• Biodegradable according to EN/DIN13432
• Thermoplasticity and therefore moldable into any object
By choosing products made of bioplastic, you also engage in the reduction of disposable solutions made of petroleum-based plastics. If you are interested in this particular material, then feel free to take a look at our PLA cups und food bowls in our online shop.