Polypropylene is currently one of the fastest growing polymers. Much of this growth is attributed to polypropylene’s ability to displace conventional materials (wood, glass, metal) and other thermoplastics at lower cost. Polypropylene (PP) is a tough, rigid plastic and produced in a variety of molecular weights and crystallinities.

Polypropylene is made from the polymerization of propylene gas in the presence of a catalyst system, usually Ziegler-Natta or metallocene catalyst. Polymerization conditions (temperature,

pressure and reactant concentrations) are set by the polymer grade to be produced.

Various production and manufacturing processes of PP exist with some general similarities. They are taking place either in a gas-phase (fluidized bed or stirred reactor) or a liquid-phase process (slurry or solution).