A radical solution to the problem of polymer waste, according to some experts, is the creation of biodegradable polymers that decompose into substances harmless to animate and inanimate nature. First, polymers were created to withstand environmental influences. Nowadays, the concept has changed: now we need polymers that maintain working characteristics during their usage period (consumption) and then undergo transformations under the influence of environmental factors and are included in the natural process of exchange.
It is believed that polymeric materials created based on plant raw materials (cereals, wood, starch, polysaccharides) degrade into completely safe components: water, carbon dioxide, biomass, and other natural compounds. That is, they provide absolute environmental friendliness of the recycling processes. Besides, stocks of plant materials can be renewed forever. However, everything is not as simple as it seems at first glance. For the idea of biodegradation of the polymer material to be realized, a combination of three main factors is required:
- appropriate environmental conditions;
- the presence of microorganisms selectively affecting the polymer material;
- polymeric materials of a particular chemical structure.
The most promising and budding plastic for the chemical industry is polylactide. Its range of uses is extensive: lamination of paper for packaging, dishes for microwave ovens, waste bags, disposable tableware, food packaging.
Biodegradable materials with active plant fillers first appeared in the 70s — 80s of the 20th century on the packaging market in the USA, Italy, and Germany. These were compositions of starch with various synthetic polymers.
Now more than 30 different polymers are considered available, which are widely used not only in the packaging market, but also in the textile industry, agriculture, medical industry, and construction. Almost all large companies in the field of polymer production offered their range of biodegradable materials. The market for biodegradable polymers is one of the fastest-growing segments of the agrochemical complex in the countries of America, Europe, and Japan.
But biodegradable polymers don’t solve the environmental problem:
- it is hard to regulate the rate of degradation in dumpsites under the influence of environmental factors;
- a rather high cost of biodegradable polymers;
- the irretrievable loss of valuable raw materials, including food, especially given the presence of hunger in particular regions of the world;
- technological difficulties in the production of biodegradable polymers;
- the safety of such materials and their degradation products on flora and fauna hasn’t been fully proven.
Therefore, according to some specialists, disposal of waste polymers through the creation and use of biodegradable materials should have a controlled application and possibly limited. The moral aspect of the problem is also discussed: does humanity have the right to use agricultural raw materials for the production of chemical products if there is hunger in the world?
Advantages of Biopolymers
Like any product of modern industry, biopolymers have their own strengths and weaknesses. This is obvious since otherwise, they would have displaced “pure” polymers from everyday life in the shortest possible time. So, the main advantages of biodegradable polymers include:
- Complete degradation in a short period: from several months to several years;
- Low toxicity of degradation products;
- Possibility of using degradation products as fertilizer.
- Safety for humans (the material doesn’t emit harmful substances while using);
- Low level of oxygen and water vapor transmission, which guarantees the safety of the product packed in such a container.
- Relative resistance of the material to degradation under normal conditions.
Use of Biodegradable Polymers
Fortunately for nature, not all branches of human activity need polymers that are strong and resistant to various factors. Therefore, the use of biopolymers is quite popular today. Although, unfortunately, not as much as conventional polymer compounds. The following industries need biopolymers:
- Consumer goods manufacturing and services. Various types of containers and tableware made of degradable polymers will significantly reduce environmental pollution with toxic plastic.
- Medicine. Suture material allows performing complex operations and firmly fixing parts of the human body with subsequent resorption of the threads in the body under the influence of enzymes and bacteria.
The field of use of biopolymers has not yet been fully studied, so we can only guess what the inventors will come up with tomorrow. The potential of biopolymers is huge. Not far off is the day when the technological capabilities of humanity will save it from an environmental catastrophe.