3 - Polyolefins

Abstract

This chapter discusses industrial processing for polyolefin production, and its classes. A polyolefin is a polymer produced from an olefin or alkene as a monomer. In organic chemistry, an alkene, olefin, or olefine is an unsaturated chemical molecule containing at least one carbon to carbon double bond. The simplest alkene is ethylene. A special family of these olefins are α-olefines, which have a double bond at the primary or a position. The most common industrial synthesis path for alkenes is the cracking of crude oil. Cracking is the process whereby complex organic molecules are broken down into simpler molecules by the breaking of carbonecarbon bonds in the precursors. There are various classes of polyolefins: low-density polyethylene, high-density polyethylene, linear low-density polyethylene, crosslinked polyethylene, polypropylene, and polybutene-1. Many processes have been developed for the polymerization of olefins. They differ in both the physical state of the reactor media and in the mechanical operation of the unit. The choice of process is determined by economics, feedstock availability, catalyst, and the desired range of products to be produced. In recent years, there has been a growing use of polypropylene materials in laundry appliances. Advances in mechanical performance and corrosion resistance have increasingly enabled advanced polyolefins to replace stainless steel in appliances, providing significant advantages in terms of material costs, manufacturing processes, and overall product design.