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Polylactic acid PLA and other bioplastics

Polylactic acid PLA and other bioplastics

PLA is not a cute diminutive of plastic but it stands for PLA polylactic acid. It is a material with interesting characteristics that we hope to see in the future in fierce competition with the plastic that we so much want to eliminate from the planet. It is a thermoplastic polyester that is obtained from corn, is biodegradable if stored under appropriate conditions, and is one of the first bioplastics to be marketed and used on a large scale, the second to be precise.

PLA polylactic acid: characteristics

It is a bioplastic that has some aspects that can still be improved, for example it is very sensitive to humidity and this can make it no longer biodegradable. At high levels of humidity it also becomes very sensitive to temperatures, so much so that above 60 ° C it even decomposes. Unfortunately today we are not able to take advantage of this advantage because the PLA is recycled along with traditional plastic.

Today this material is beginning to spread and to no longer be a niche. The first sector that sees it used is that of packaging in which we find 70% of that produced. Let's imagine food packaging such as milk and bread, juices and water, but also perfumes, soaps and fats. For now it is necessary to pay close attention to hot liquids, they cannot be stored in PLA polylactic acid containers because this material would lose its consistency and become soft.

In the meantime, while trying to improve its characteristics, it has also begun to be used in other contexts with interesting but still experimental results. For the agricultural sector it is still too expensive while for cars it may be affordable. We find on the market some cars with coatings made with blends of PLA and fibers. There are attempts to use PLA even in the computer world. Fujitsu already produces injection-molding keyboard keys and computer cases, while Sony has started producing electrical equipment cases with 85% PLA. In Japan, the first compact disc entirely in PLA was also created, with a single cob we can produce about ten.

Other bioplastics. features

When we talk about bioplastics we try to find an alternative to traditional plastic that has a lower impact on the environment because it is made from organic and therefore non-polluting material.

Before we saw that it can be obtained from corn but not only: they exist bioplastics which also come from wheat, beet or other cereals. The goal is to arrive at a material comparable to plastic but absolutely biodegradable that after a few months disappears from the face of the Earth as if by magic or becomes a fertilizer to fertilize our fields. Traditional plastic, made from petroleum, remains for unimaginable times.

One of the products that we can have in our hands is the bioplastic bag, not always easy to recognize, the only solution is to check the presence of the wording "biodegradable and computable". If the European standard is mentioned (UNI EN 13432: 2002). And finally if the trademark of a certifying body appears, which protects the consumer as a third party (Cic, Vincotte and Din Certco are some of the best known).

For what concern recycling process it is important to know that only bioplastic can be recycled together with virgin plastic, when it reaches the end of its life cycle only for 10%. It is necessary to dispose of it separately in order not to ruin the recovery of virgin plastic because only I enter the 10% threshold, bioplastics they do not damage in any way the separate collection of virgin plastics. At home we must pay close attention and put biodegradable packaging, dishes and glasses in the organic fraction, in the waste bin, in biodegradable bags.

Other bioplastics: use

Let's see how the bioplastic, with some success. We find it in cultivated fields, in bioteli for mulching where it solves the problem of waste disposal because the film is left to decompose in a natural way.

And in the future? There are high hopes for biopolymers which, according to a study by the University of Utrecht, could replace most of the plastics of petroleum origin. The game is still to be played but in the meantime bioplastic production could double over the next decade but the question of costs, too high and not very competitive, must certainly be resolved. There is certainly a more present awareness of many countries and institutions of the danger of a plastic invasion and we are seeing many courageous initiatives and positions but it is very important that being an environmentalist stops coinciding with having to break the budget.



Video: Biodegradable Plastic PLA+Starch Compounding and Pelletizing Twin Screw Extruder Machine (January 2022).