453. Why is it so expensive to recycle plastic?
Different plastics are handled differently for recycling. Thermosets, such as rubber in tires, cannot be melted and cannot be recycled. Only thermoplastics can be melted for true reuse. There are 6 common thermoplastics that are recycled. These are numbered 1 through 6 on their bottoms. Objects made from one of these plastics can be collected together, melted, and then reformed into new useful objects. Unfortunately, the melted and reformed plastic isn't as pure as the original. The plastics manufacturers would rather clean up petroleum into petrochemicals and then make pure plastics than start with plastic objects, clean them, and reuse them. Because the recycler can't control what was in the plastic objects, these objects cannot be used for critical applications such as food containers or plumbing. Thus most recycled plastic is used for less profitable applications. If the recycler could be absolutely sure that the plastic hadn't been contaminated, some of it could be reused very easily. Plastic milk jugs could be reformed into plastic milk jugs over and over again.