Polystyrene is made in a process known as suspension polymerization. After styrene is produced by combining ethylene and benzene, it is merged with water and a mucilaginous substance to form droplets of polystyrene. Next, the droplets are heated and combined with an initiator, which begins the process of polymerization. The droplets combine to form chains, which in turn combine into beads. Stopping the process with terminators is difficult, since the chains must be of a certain length to be of use.
that protects the earth against harmful ultraviolet rays from the sun. In 1988 representatives from 31 nations signed the Montreal Protocol, a treaty with which they resolved to halve CFC production by 1998. This agreement brought EPF to the world's consciousness as a threat to the ozone layer. While foam packaging is responsible for less than three percent of the CFCs being released into the atmosphere, EPF reduction has been targeted as a way to lower CFC levels, and new technology that explores ways to produce EPF without CFCs has flourished. EPF has also been singled out by environmentalists because it is not being recycled. Action has been taken, however, and programs are under way to see that a greater percentage of EPF will be recycled in upcoming years.