We cannot imagine our daily life without plastics. Generally, the day starts and ends with a toothbrush, typically completely made of plastics. Plastics take over varying tasks, like packaging for the protection of food or medicine ensuring the products’ hygiene and durability. As plastics barely conduct heat, houses are isolated with corresponding insulating materials to avoid heat loss. Polymer components almost do not corrode, are light-weighted but durable and thus are resistant to many outside influences over a long period. Apparel made of synthetic fiber textiles or of synthetic fiber components can provide comfortable wearability properties as well as functionalities such as water repellency and/or breathability.
However, we should not oversee the disadvantages of polymers and their occurring hazards. Immediate advantageous properties, like outstanding durability, could be a tremendous disadvantage if it is disposed in nature. Then, polymers are only degraded extremely slowly in nature and will remain as waste for centuries to come. In addition, we can nowadays find nano plastic particles everywhere: added in toothpaste or detergents, to improve its cleaning impact, or in cosmetics to boost the covering power.
Biopolymers make the difference
Next to these environmental and health hazards, there remain other non-solved functionality deficiencies related to petro-chemical plastics. For instance, compound systems from different plastics are required to achieve varied barrier effects in packaging to protect food. These systems lead to a limited recyclability and lastly to a “downcycling”, as these materials, produced at great effort, cannot be separated at their end of life.
Therefore, it is important to substitute petro-chemical plastic products with environmentally friendly alternatives at large scale as soon as possible. These alternatives must ensure the positive application properties of plastic materials in daily use and must not lead to the mentioned, negative environmental impacts and health hazards. “Bioplastics” lend themselves as these alternatives due to their nearly similar characteristics, related material properties and manufacturing processes. On top of that, we can expect properties (e.g., barrier effects) of certain biopolymers that cannot be met by petro-chemical plastics. The most well-known, technically usable, bio-based polymers comprise polylactide (PLA), polybutyl-succinate (PBS), an polysaccharides like starch and polyhydroxyalkanoate (PHA).