writes "Plastics which form by chemical reactions in the presence of heat are very useful. They can be very strong, and if you incorporate appropriate "filler" materials (chalk, glass fibre, carbon fibre), they can have very attractive engineering properties. But .. that chemical reaction makes them very difficult to recycle, because the new chemical formed during the reaction will often char before it melts. We're not talking about thermo-plastic polymers here (e.g. nylon, polypropylene, PET), but thermo-setting ones including epoxies, phenol-formaldehyde resins, etc.
But no more : an international team have discovered a new class of polymer-forming reactions that produce a thermo-setting polymer, but they can recover the initial components by digesting the polymer with moderately strong acid (pH 2 ; I'd wear gloves. And glasses.), so after a component is used and obsolete, or broken, it can be separated reasonably easily into it's original components (including valuable reinforcing materials, such as carbon fibre) and these then re-used. That is a pretty big step forward."Link to Original Source