Referát: Polyethylene and its properties

Plastics are organic polymeric materials (those consisting of giant organic molecules) that are plastic—that is, they can be formed into desired shapes through extrusion, moulding, casting, or spinning. The molecules can be either natural—including cellulose, wax, and natural rubber—or synthetic—including polyethene and nylon. The starting materials are resins in the form of pellets, powders, or solutions; from these are formed the finished plastics.