What is PLA?
Polylactic acid ( abbreviated as PLA) is a type of plastic that has become very popular i.a. because it can be produced cheaply from recyclable resources such as maize starch (and therefore not petroleum/oil, like normal plastic). Plastic types produced from biomaterial (such as PLA) are also known as bioplastics. In 2010, PLA was the second most used bioplastic in the world (measured by volume). However, it is the most used material within 3D printing.
PLA is also popular because it can be used for the production of many different things. In addition to 3D printing, it is also used for making of:
- Plastic bottles
- Biodegradable medical devices (such as screws and plates that are expected to degrade within 6-12 months)
- Prototypes within pharma and other industries
PLA has a low melting point of around 160 °C, which makes it ideal for 3D printing, as you do not have to spend much energy on heating in the production process. However, it also has the disadvantage that it can limit the possibilities of use, as deformations will occur in the product if you used it in, for example, an oven.
How is it produced?
As previously mentioned, PLA is made from renewable and natural resources such as maize. The starch in corn is extracted from plants and converted into dextrose by adding enzymes. It is then converted into lactic acid using microorganisms, which can eventually be made into PLA. This process results in PLA resembling petroleum-based plastics on a molecular level.
It is very positive that PLA is made from recyclable resources, as traditional production methods of plastic use oil, which is a limited resource. But of course a question arises as to whether food should be used to produce plastic instead of using it to feed the world's population.
Is it that environmentally friendly?
Although there are elements of "greenwashing", PLA is biodegradable and therefore a step in the right direction away from plastics made from oil. In addition to being plant-based, the production of PLA also significantly fewer greenhouse gases and use much less energy in the production process.Does this mean that you can just throw it into nature without thinking?
Biodegradable should not be confused with compostable, as there are important differences between these 2 definitions and they are often misunderstood. A biodegradable material can be broken down under certain conditions. PLA can be 100% recycled if it is included in the recycling system. Although it is labeled as biodegradable, it only breaks down in nature under the right conditions and becomes, for example, only partially degraded over a period of 6 months at a temperature of about 60 °C. However, it can be burned and produce only carbon, oxygen and hydrogen at the combustion
So you can't just throw it into nature and have a clear conscience. The best is still to include it in the recycling system.
Why do we use it at WeShape?
At WeShape we use PLA in our production because:
- It is the most environmentally friendly alternative. Although it is far from a natural product, it is still better for the environment than traditional plastic.
- In addition, there are also some practical advantages of PLA, e.g. that it has a relatively low melting temperature, which is an advantage in the printing process
- It is relatively cheap, which means it is also cheaper for our customers
- It is a reliable material, as there has been a high use of PLA for a long period. This has meant that massive investments have been made in making high-quality PLA, which gives good and stable prints in a 3D printer.