Polyolefin

Polyolefins is a collective term for produced from alkenes such as ethylene, propylene, 1- butene or isobutene by polymerization of polymers such as polyethylene and polypropylene.

There are saturated hydrocarbons which are the most abundant group of plastics. Polyolefins are semicrystalline thermoplastics can be processed easily. They are characterized by good chemical resistance and electrical insulation properties.

Polyolefins represent 11.2 million tonnes about 47 % of Europe's total annual consumption of plastic from 24.1 million tons dar.

Raw materials

The raw materials ethylene, propylene and C4 olefins are mainly from petrochemical steam crackers processes. Renewable resources such as ethanol from sugar cane provide regionally another source of ethene dar. by dehydration

α - olefins such as 1 -hexene derived inter alia from the SHOP process by oligomerization of ethene.

Production

The starting monomers - propene and ethene - are gaseous at room temperature, forming at their concatenation ( polymerization) long molecular chains, the so-called polymers.

The polymerization requires high temperatures, often high pressure and the use of a catalyst system. The catalysts used are usually mixtures of titanium and aluminum compounds. Without such substances, the polyolefin production is not feasible, that is, the success of the polyolefins is based to a large extent on the development of ever more efficient and more complex catalyst systems.

Polyolefins are robust, flexible plastic with many applications.

End products

The main representatives of this group of plastics are polyethylene (PE), polypropylene (PP ) and polymethyl (PMP ). Furthermore, polyisobutylene (PIB) and polybutylene (PB, polybutene -1) polyolefins industrially produced and used.

Of low density polyethylene ( LDPE / LDPE ) are prepared films, blown films, shrink films, shrink tubing, and coatings packaging. From linear low-density polyethylene ( LLDPE / LLDPE ) packaging and plastic containers are mainly produced. High-density polyethylene ( HDPE / PE -HD) is a raw material for the manufacture of containers, toys and gasoline tanks, pipes and household goods. Polypropylene (PP), especially isotactic polypropylene, is used as a packaging in the medical and food industry, for the fibers and tubes.

Flexible polyolefins ( FPO) are used since the early 1990s widely as FPO geomembranes for waterproofing and serve as an alternative to the previously common PVC geomembranes.