Obviously, monomers don't think. Which means that they don't wake up one day and decide they want to join up with a bunch of other monomers and create a polymer. Rather, monomers link up with their own kind with the help of a chemical reactor, a device that facilitates controlled chemical reactions. UC Berkeley's Kingsbury explains a bit about how the monomer-to-polymer reaction takes place.
"Typically, you would have to keep them at high temperatures or high pressures or with some solvent to keep them flowing. Otherwise, reactors get gummed up with a giant chunk of plastic," Kingsbury says. Once out of a reactor, resins come out of the factory door as pellets that look like grains of rice, which are shipped to companies that make them into a wide variety of products.
The impacts resins have on the environment are varied. First of all, the very fact that they are derived from oil and natural gas means the use of a substantial amount of fossil fuels, albeit far less than what's used for, say, transportation. But the environmental effects of resin wastes go even further.
"[Resins] are known for being flammable and toxic, and the fumes produced after they catch fire are quite dangerous," says Ross O'Lochlainn, who works with ERA Environmental Management Solutions, an environmental consultancy.
O'Lochlainn says that the use of resins as surface coatings and applications requires them to be sprayed as part of a volatile mixture of chemicals, known as volatile organic compounds (VOCs). "These chemicals are required as the delivery medium, and because of their volatility, they evaporate quickly, leaving behind the resin coating. These VOCs are harmful to the environment and are closely monitored by environmental protections agencies," he says.
O'Lochlainn adds that resin mixtures can lead to the contamination of waterways if, for example, they're poured down the drain. Most wastewater treatment plants aren't designed to break down the chemicals and simply discharge them.