Bioplastic
Gigantic amounts of plastic waste continue to end up in our environment and especially in our oceans. From shampoo bottles to plastic bags, the dimensions of this pollution are devastating and the effects hardly foreseeable. That “something” must be done is clear. However, completely eliminating plastic packaging seems unrealistic. After all, products such as cosmetics must be able to be offered in a hygienic and user-friendly manner. But a rethink is increasingly taking place among both suppliers and customers. More and more people want sustainable packaging to relieve the burden on our environment. But what can be the solution? One alternative for conventional plastic made from petroleum, which is increasingly on the rise, is said to be bioplastic. The possibility actually sounds sustainable and sensible. But what is actually behind it?
What is bioplastic?
First of all, the term bioplastic is not exactly defined. It can therefore either be plastic made from biological raw materials or plastic that is biodegradable. A material is always considered biodegradable if it can be broken down into its components again with the help of organisms. So, for plastic to be called bioplastic, at least one of the two criteria mentioned must be met. Understandably, it is not easy for consumers to keep track of this.
Renewable raw materials that can be considered for the production of biobased plastics do exist: corn, sugar cane or cellulose, for example. Already known, commercially available biobased plastics are cellulose derivatives such as cellulose esters (CA), the group of polyhydroxyalkanoates (PHA) and polylactide (PLA).
The current global market leader for biobased plastics can be found in Brazil. It has developed a process for the production of polyethylene based on bioethanol produced by fermentation.
This bioalcohol is in turn obtained from sugar cane. While bio-polyethylene has the same properties as conventionally produced polyethylene, it is also not biodegradable. Biodegradable bioplastics often decompose at low temperatures, which is why they cannot normally be used for all applications. For this reason, special substances are usually added to the bioplastic to prevent or at least slow down the rapid decomposition at low temperatures. However, these additives often prevent bioplastics from biodegrading.It must also be borne in mind that the cultivation of the raw materials is very energy-intensive and costly, and that fertilizers and/or pesticides are usually used in industrial agriculture.
The second group, which includes bioplastics, comprises biodegradable plastics. Here, the starting material is initially irrelevant, but it is important that it is at least 90 percent degradable. According to the DIN EN 13432 guideline (proof of compostability), a maximum of ten percent of the original mass may remain after three months of composting and subsequent screening through a sieve (2.00 millimeters). For biodegradability in aqueous media, it must be possible to demonstrate that at least 90 percent of the organic material is converted to CO2 within six months. If these requirements are met, bioplastics can receive DIN EN 13432 certification. It should be noted here that the biodegradable plastics do not necessarily have to be made from animal or renewable plant raw materials. Plastics made from fossil resources are also permissible for certification as bioplastics, provided they are biodegradable.
Other examples of bioplastics
Polyhydroxybutyric acid, a polyester that can be fermentatively produced from renewable resources, also falls under the bioplastic designation. The advantages of this material are primarily its biodegradability and simultaneous biocompatibility. As a packaging material for cosmetics, polyhydroxybutyric acid is basically very well suited, thanks in part to its hydrolysis and UV stability. PHB is also characterized by excellent tensile strength. Polyhydroxybutyric acid is also suitable for medical applications and/or contact with food. The material can be dyed, printed, and glued. It is non-toxic and free of catalysts. In nature, PHB can be degraded by bacteria, algae, or fungi, with the rate of degradation depending on the strength of the material and the environmental conditions. However, decomposition is also possible by hydrolysis as well as by mechanical, oxidative, thermal, or photochemical stress.
The production of bioplastics in the form of a fermentative synthesis is usually based on sugar (glucose) and starch. However, fermentative extraction from glycerol is also possible.
Polylactic acid (PLA) also falls into the bioplastic category. These are biodegradable or compostable and biobased polyesters produced from lactic acid. As a bioplastic, polylactic acid is a clear colorless thermoplastic with properties similar to polyethylene terephthalate (PET) and medium brittleness. Other advantages include low flammability and high capillary action. The areas of application for pure polylactic acid as a bioplastic are very diverse. The material is used in the packaging industry (also for cosmetics), for hygiene products, diapers, and organic garbage bags. PLA also lends itself to the biomedical sector. PLA starch blends are also frequently used in the catering sector, as they are suitable for use as tableware, for example. However, polylactic acid is relatively problematic for already established recycling processes due to its high temperature sensitivity, but with the help of various special methods, the material can be recycled well.
The possible disadvantages of bioplastic
Even though biobased plastics is a more sustainable alternative to conventional plastic, there are also disadvantages. For example, domestic compost hardly provides the ideal conditions for bioplastics to decompose. The Federal Environment Agency has even spoken of a deceptive package in this context. Many biodegradable plastics decompose during composting only under the special conditions of industrial composting plants. The (usually lower) moisture and temperature conditions of the domestic compost heap, on the other hand, mean that bioplastics do not decompose at all or only after a significantly longer time. If bioplastics end up in the sea, they take just as long to decompose as conventional plastics. For the environment and animals, bioplastics are therefore just as dangerous and harmful as conventionally produced yogurt pots and plastic bags. However, if cosmetics packaging made from bioplastics ends up in industrial composting plants, it is definitely a sensible alternative to conventional plastic packaging.
The market situation for bioplastics
In 2007, consumption of biodegradable bioplastics in Western Europe was around 60,000 to 70,000 metric tons. This represents less than 1.0 percent of the total plastics market. However, the growth rates are enormous. Consumption of biodegradable bioplastics based on sugar, starch and cellulose alone increased by 600 percent between 2000 and 2008. For 2007, global production capacity for biodegradable bioplastics was 315,000 metric tons, of which all 189,000 metric tons were produced on the basis of renewable raw materials. Europe is ahead of North America (80,000 tons) with a production capacity of 140,000 tons. The global market for bioplastics is expected to grow even more significantly by 2021, reaching a volume of around $5.8 billion. That would still be more than three times as much biobased plastics as in 2014. Finally, there are good reasons to support the further development of bioplastic. As is well known, crude oil is not available in unlimited quantities, and every piece of bioplastic that is not made from the finite raw material helps to save resources.
Currently, bioplastic is still and mostly put in the residual waste due to ignorance. However, degradable bioplastics can of course be disposed of in the organic waste garbage can.
The right packaging for your needs
Bioplastics made from biological raw materials or biodegradable plastics are an alternative for conventional plastics made from petroleum. Cosmacon is happy to help you choose the right packaging. In cooperation with packaging distributors, we will find sustainable packaging made from bioplastics for you. For less plastic waste in the environment and a conservation of petroleum resources.
Sources:
Innovations in applications and prospects of bioplastics and biopolymers: a review.; Environ Chem Lett. 2022;20(1):379-395.
Production of bioplastic through food waste valorization.; Environ Int. 2019 Jun;127:625-644.
Poly(lactic acid) (PLA) and polyhydroxyalkanoates (PHAs), green alternatives to petroleum-based plastics: a review.; RSC Adv. 2021 May 10;11(28):17151-17196.
Bioplastics: A new analytical challenge.; Front Chem. 2022 Sep 23;10:971792.