Also called macromolecule, a polymer is a gigantic molecule that has a chain of hundreds or even thousands of monomers (molecules) or smaller organic molecules attached to each other. Every polymer molecule is primarily a long carbon atom chain. The word ‘polymer’ in Greek means ‘many’ (poly) and ‘parts’ (mer), or many parts. These monomers bond to each other through polymerization to form a polymer. For example, ethylene is a monomer that turns into polyethylene when polymerized. Polyethylene is a polymer found in plastic.
Polymers can be naturally available or man-made. Starches, DNA, fats and proteins are examples of natural polymers. Rubber is a natural form of polymer and is known for its elastic traits. Artificial fibers and plastics are made from synthetic polymers. In fact, plastic is another name for polymer.
Structure and Molecular Arrangement
Most common polymer classes comprise hydrocarbons, and hydrogen and carbon compounds. These are polymers particularly developed from carbon atoms bonding together, into long chains. This chain forms the polymer’s backbone, and thanks to carbon’s nature, one or multiple other atoms could attach to the carbon atom. And there are polymers that comprise only hydrogen and carbon atoms.
For example, polyethylene, polystyrene, polypropylene, etc. are such polymers. Other commonly made polymers may comprise non-carbon elements. For example, polycarbonate and polyester contain oxygen. Some polymers may have the carbon backbone replaced by a phosphorus or silicon backbone.
A polymer could be linear or branched. Most polymers are linear in which molecules are attached to each other in a sequence, forming a long chain. This linear chain need not be a rigid, straight line. The chain could swivel or overlap a fair bit, but it would only have one ‘beginning’ and one ‘end’. In other words, the chain won’t have branches. The branched polymer, as the name indicates, has branches or additional beginnings along the chain, which means there are multiple ends as well.
Polymers can be made of different kinds of molecules or monomers, which determines how the polymer ends up being. Ultimately, how polymers feel, act and look depend on the arrangement of their molecules and atoms. Polymers can be elastic, rubbery, sticky, tough, soft, brittle and/or impact-resistant. Also, they could be translucent, inelastic, reflective, and have insulating traits.
Polymers are unreactive, which means they are ideal to safely store chemicals and food. The majority of polymers such as polypropene and polyethene aren’t biodegradable, so they cannot be broken down by micro-organisms. These polymers make good garbage dumps. Polymers can also be incinerated to create heat energy and generate electricity. However, such burning can release loads of carbon dioxide, and also many toxic gases if the incineration isn’t done at high temperatures.
As aforementioned, synthetic polymers are made through a chemical reaction called polymerization, which entails bringing together several monomers sequentially, to form a chain. Polymerization is not a standard process and can be conducted in different forms. However, pressure, heat, and catalysis are common in every polymerization process. Polyethylene, polyvinyl chloride, polypropylene, polystyrene, polyurethane, polyamide, etc. are polymers that can be prepared synthetically.
Polymers are used in several industries such as medicine (biomaterials like polyurethane, Teflon, and Dacron), consumer science (plastic containers, clothing, garbage disposal bags, etc.), manufacturing industry (automobile components such as windshields), sports equipment, etc. Polypropylene is a polymer used in the upholstery and carpet industry.
A low-density polymer, polyethylene is common in plastic grocery bags. Different polymers could also be used in pipes and decks (polyvinyl chloride), plastic bottles (polyethylene), toys and detergent bottles (polystyrene), nonstick pans (polytetrafluoroethylene), face shields and skylights (polymethyl methacrylate), wetsuits (polychloroprene) and paints (polyvinyl acetate).