Thermoset plastics contain polymers that form irreversible chemical bonds that make strong products that cannot be remelted: vulcanized rubber for tires, Bakelite kitchenware, jewelry and circuit boards, epoxy resins, Duroplast car bodies and toilet seats, polyurethane cushions, insulation and windshields, et cetera.
Styrofoam cups and egg cartons cannot be recycled without (rare) specialized equipment and processes.
Moreover, even thermoplastics can be recycled only 2-3 times, before their polymer chains get shortened to the point where quality and durability become so low that the products are unusable.
(Newspaper, magazines, copying paper and Kraft paper bags have the same degradation problem: 6-7 trips to the recycler, and the cellulose fibers are too shortened, damaged and degraded to be reused. Steel, aluminum and glass, by contrast, can generally be recycled endless times.)
All these complexities explain why only a small fraction of plastics are recycled. ExxonMobil recycling 60,000,00-80,000,000 pounds of plastics per year may seem minuscule, compared to 73,000,000 tons of annual US plastic waste. However, it’s equivalent to 430-570 offshore wind turbine blades (350 feet long; 140,000 pounds apiece) that only end up in Grand-Canyonesque landfills.
Plus, plastic wastes can also be converted into diesel, aviation and gasoline fuels, and even electricity.
An excellent solution is to turn plastics and most other garbage into electricity for our increasingly power-hungry society – especially as AI and data centers proliferate, and politicians mandate that we convert our gas stoves, ovens, furnaces and water heaters to electric models.