Because plastic is resistant
Researchers Jorge Conde, Aurelio Ramírez and Leticia Navarro, from the Institute of Applied Chemistry of Unpa, developed a chemical process that uses ethylene glycol (C2H6O2) and potassium hydroxide (KOH) to destroy the polymeric chains that make up PET.
In an interview for Agencia Informativa Conacyt, Dr. Jorge Conde emphasized the negative impact of the accumulation of PET bottles, mainly in seas and rivers, because they cause the death of species.
Regarding the side effects of the chemical process, he mentioned that it is less aggressive compared to other methods used by the industry, and that it is carried out in a controlled environment.
The chemical process proposed by Unpa researchers decreases temperature conditions and uses less toxic chemicals, unlike the hydrolysis used by some industries, which releases toxic substances into the environment. In addition, the process can be used for PET recycling.
Table of chemical resistance of plastics
There are seven raw material polymers in use today: polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, polystyrene, polycarbonate and poly(methyl methacrylate) (Plexiglas). These make up 98% of all polymers and plastics present in everyday life. Each of these polymers has its own characteristic degradation modes and resistance to heat, light and chemicals. Polyethylene, polypropylene and poly(methyl methacrylate) are sensitive to oxidation and UV radiation,[2] while PVC can discolor at high temperatures due to the loss of hydrogen chloride, thus becoming brittle. PET is sensitive to hydrolysis and attack by strong acids, while polycarbonate depolymerizes rapidly when exposed to strong alkalis.[1] PET is also sensitive to hydrolysis and attack by strong acids, while polycarbonate depolymerizes rapidly when exposed to strong alkalis.[1] PET is also sensitive to hydrolysis and attack by strong acids.
Increasing chain polymers such as poly(methyl methacrylate) can be degraded by thermolysis at high temperatures to give rise to monomers, oils, gases and water.[3] Degradation takes place by:
Plastic corrodes easily
Aluminum foil: It is an element that can be found in any home, it is a simple solution to eliminate rust, just cut pieces of aluminum foil, moisten it in water or vinegar and rub it on the rusted material and it will magically disappear.
Sodium chloride (salt) and lemon juice: The oxidized part is covered with salt and the juice of a lemon is added, after an hour, it is removed, rubbing the oxide with a brush of strong bristles until eliminating it, it is washed with water and ready, likewise, this mixture, serves to eliminate the stains of the oxidized fabric.
Baking soda and lemon: The chemical reaction resulting from the union of these substances is ideal to carry out the process of rust removal. Mix two tablespoons of baking soda and the juice of a lemon, stir until a pasty form is obtained, apply it to the rusted surface and clean it strongly with sandpaper.
White vinegar: It is an acid that reacts when it enters in contact with the oxidized metal, it eliminates the oxide. The piece is soaked in the vinegar for a while, then with a scouring pad it is cleaned by scrubbing it strongly.
Why plastics do not rust
PVC outdoors yellows and releases dust, the agricultural film becomes rigid and brittle in the sun and loses its flexibility properties. Therefore, the property of not degrading is not only convenient or necessary, but indispensable, because being already a material with many advantages over the others, it is even more suitable not only for the application of the 3R’s (Recirculate, Reuse, Recycle) but also for the application of the four M’s Less weight, Less volume, Less cost and Less electrical energy consumption, great advantages against competing materials.
With the purpose of appearing advanced, modern, in, cool or smart, many influential people and institutions use terms out of place because their indiscriminate, generalized, popularized use debases what wanted to be something positive. As examples we have the term recycled, now everything is recycled without basis or study, simply a very popular term used dishonestly.
The fact that its presence is very apparent in garbage dumps or in dirty streets does not make it polluting. The problem is different. We repeat, it is not pollutant because it does not react chemically with other materials, therefore it does not form undesirable products.