People have been using polymers since the Stone Age: wool and leather are made up of proteins, cellulose is the main component of fabrics, papyrus and paper. Once in the environment, such polymers decompose rather quickly. At the beginning of the 20th century, mankind mastered the production of synthetic polymers. Products made from them turned out to be light and strong, but ... The advent of the polymer age was overshadowed by the inability of nature to quickly destroy such compounds. As a result, "man-made" polymers accumulate in gigantic quantities in landfills, and scientists are looking for ways to save the Earth from destructive plastic.
Polymers, despite their low specific gravity, have a high molecular weight. In these compounds, certain elements are periodically repeated - structural links. In fact, polymers are as old as life. The essential components of living systems include proteins, nucleic acids and polysaccharides. These polymers are called natural. Those that appeared thanks to man are artificial and synthetic.
Artificial polymers are obtained by chemical modification of natural ones. The first artificial polymer, nitrocellulose, was produced in 1829 by the Swiss chemist Christian Friedrich Schönbein. Initially, nitrocellulose was used to replace ivory products (for example, billiard balls) and to produce photographic and film films. Now, mostly smokeless gunpowder is made from it.
Synthetic polymers are those that are obtained by polymerization or polycondensation of low molecular weight compounds (most often refined products). We usually call them "plastic" in everyday life. Five synthetic polymers are produced on the largest scale: polyethylene, polypropylene, polystyrene, polyvinyl chloride and polyethylene terephthalate.
The method for producing the first synthetic polymer was patented in 1909. The phenol-formaldehyde resin, which hardens when heated, was named Bakelite after its inventor, Belgian chemist Leo Bakeland. Yet the era of industrial synthetic polymer production is believed to have begun in the 1950s, when Karl Ziegler and Giulio Natta developed catalysts to make polyethylene and polypropylene without high pressure and temperature. Thanks to Ziegler-Natta catalysts, the chemical industry quickly mastered the production of construction and packaging materials.
But less than ten years later, environmentalists began to sound the alarm. As early as the 1960s, it was clear that the growth in the production of disposable bags and food packaging posed a threat to the environment. Waste plastic began to litter city streets, suburban areas and even the seas. The fears were confirmed. If in the 1950s no more than 2 million tons of plastics were produced per year, then in 2015 their output increased to 400 million tons. At least 4 billion tons have been shipped from the factories over the past 13 years. Simplicity and large volumes of production have led to the fact that plastic products have really become disposable: only 9% of all produced synthetic polymers were recycled, another 12% was burned in the furnaces of incinerators and thermal power plants. It is easy to calculate that 79% of the plastic ended up in landfills, landfills and simply in the environment. More than 8 million tons of synthetic polymers enter the World Ocean annually. Sea and ocean currents collect them into "garbage islands", which, over time, risk turning into "garbage continents". By 2050, the total mass of polymer waste will be 12 billion tons.