Two federal agencies, the Drug Enforcement Administration and the Food and Drug Administration, determine which substances are added to or removed from the various schedules, although the statute passed by Congress created the initial listing.
Polycarbonate is a versatile, tough plastic used for a variety of applications, from bulletproof windows to compact disks (CDs). The main advantage of this material over other types of plastic is its great strength combined with light weight. While acrylic is 17% stronger than glass, polycarbonate is nearly unbreakable.
Polyethylene is a thermoplastic polymer consisting of long hydrocarbon chains. Depending on the crystallinity and molecular weight, a melting point and glass transition may or may not be observable.The temperature at which these occur varies strongly with the type of polyethylene.DPE has a high degree of short and long chain branching, which means that the chains do not pack into the crystal structure as well. It has, therefore, less strong intermolecular forces as the instantaneous-dipole induced-dipole attraction is less. This results in a lower tensile strength and increased ductility.