Polypropylene (PP plastic) belongs to thermoplastic polymers, partially crystalline, which is obtained from the polymerization of propylene (or propene). It belongs to the group of polyolefins and is used in a wide variety of applications that include packaging for food, textiles, laboratory equipment, automotive components and transparent films. It has great resistance against various chemical solvents, as well as against alkalis and acids.
Polyethylene (PE plastic) is chemically the simplest polymer. It is represented with its repetitive unit (CH2-CH2) n. Due to its high global production (approximately 60 million tons are produced annually (2005) around the world) it is also one of the cheapest polymers, being one of the most common plastics. It is chemically inert. It is obtained from the polymerization of ethylene (with the chemical formula CH2 = CH2 and called ethene by IUPAC), from which it derives its name.
This polymer can be produced by different polymerization reactions, such as for example: Free radical polymerization, anionic polymerization, polymerization by ion coordination or cationic polymerization. Each of these reaction mechanisms produces a different type of polyethylene.
It is a straight-chain unbranched polymer. Although the ramifications are common in commercial products. The polyethylene chains are placed under the softening temperature Tg in amorphous and semicrystalline regions.
PP plastic polypropylene and polyethylene PE plastic are two of the most used polymers, polypropylene was developed during the space race, looking for a lightweight material and with good impact resistance.
Polypropylene and polyethylene, is among the most economical plastic materials for the production of plastic parts.
Both polyethylene PE plastic and polypropylene PP plastic can be found, either in natural or additive with fiberglass / mineral filler. To give the base plastic more strength and / or rigidity, and dimensional stability.
Among the polymers, special mention must be made of polypropylene with long fiber, this plastic has unique characteristics that make it a viable substitute for iron and steel in a multitude of industrial and consumer goods applications. The versatility of polypropylene with long fiber together with its inferior wreck to other solutions, makes it arise in the short term as one of the materials with more commercial and industrial travel.
Polypropylene and polyethylene:
- Plastics that can be colored easily.
- They have an excellent behavior to chemical agents.
- They are plastics that have a good memory and resistance to stretching.
- Plastics that have an excellent impact behavior.
- We can find them UV resistant and / or flame retardant, although they are much more expensive than natural polypropylenes, too.
- These plastics are widely used in all areas of activity, especially toys, furniture, automotive, furniture sector …
- They are plastic that can be injected through the use of injection molds.