>Are picoplastics possible? A single hydrogen atom is about 0.1 nanometers in diameter. You can't really have complex molecules that are smaller than nanometer

>Are picoplastics possible? A single hydrogen atom is about 0.1 nanometers in diameter. You can't really have complex molecules that are smaller than nanometer scale. >And what would single molecule of plastic be called? A monomer is what the smallest unit of a polymer is called. They're a single molecule, but so is a long polymer chain of a bunch of them bonded together, and the properties of the material often depend heavily on the number of monomers in the average chain in the bulk material. For example, the monomer of polyethylene, one of the most common plastics, is a gas at room temperature/pressure. So it may not really make sense to call a monomer a molecule of plastic.