Recycling of plastics is a troublesome business.
If plastics are broken down into their constituent parts in the refining process, the products obtained are simply ones which can be made more cheaply from oil, especially when the costs of collection and separation of the waste to be recycled is taken into account. Things would naturally be different, if it were possible to make useful chemicals from old plastics which the chemical industry can only produce at great cost by other methods. This idea is at the heart of a technique now proposed by American chemists Ayusman Sen and Anne Pifer from Pennsylvania State University.