ethylenepropylene
Ethylenepropylene, in polymer science, refers to ethylene–propylene copolymers (EPCs), a family of polymers formed by polymerizing ethylene and propylene monomers. These copolymers are typically produced by coordinated-type catalysts (Ziegler-Natta or metallocene) and can be tailored by adjusting the ethylene-to-propylene ratio and polymerization conditions. The resulting materials range from flexible, rubbery elastomers to rigid, tough plastics. The copolymerization disrupts the crystallinity of polypropylene, yielding materials with improved clarity, impact resistance, and low-temperature flexibility compared with polypropylene homopolymer. The density is generally between that of polyethylene and polypropylene, and crystallinity is reduced relative to homopolypropylene due to random incorporation of ethylene units, resulting in materials with good impact resistance and clarity. The related ethylene–propylene–diene monomer (EPDM) is a distinct class of elastomer that includes a diene for crosslinking.
Applications: widely used in packaging films, automotive seals and weatherstrips, hoses, tubing, electrical insulation, and general-purpose
Processing: EPCs are produced in slurry, gas, or bulk processes and can be melt-processed by extrusion, injection
Safety and environment: as with most polymers, EPCs are chemically inert under normal use but can release