What type of plastic is PP?

Polypropylene uses

This plastic works well as an aroma barrier, providing good protection for food packaging. It is impermeable, unbreakable, glossy and lightweight, and can be presented in both rigid and flexible forms. It has good temperature resistance, so that hot products can be packaged in polypropylene containers.

Polypropylene is produced from petroleum or natural gas by a polymerization process. These polymers are solid thermoplastics that can be processed by extrusion and by molding or injection molding.

Most modern PP production processes have no liquid or gaseous effluents. Being 99% carbon and hydrogen, which are harmless and abundant in nature, PP is chemically non-polluting.

PP contains energy comparable to fossil fuels, making PP waste an excellent alternative for use as a fuel to produce electricity and heat.

Polypropylene disadvantages

Industrially manufactured polypropylene is a linear polymer, the backbone of which is a saturated hydrocarbon chain. Every second carbon atom of this main chain has a branched methyl group (CH3). This makes it possible to distinguish three isomeric forms of polypropylene:

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Impact copolymers are ethylene-propylene block copolymers that exhibit high impact strength at both ambient and low temperatures. The product line offers an extensive range of fluences. The range of impact resistance extends from moderate to very high, with materials having a high rubber content and high impact resistance at very low temperatures. At the other extreme is 2240P, which is a moderate impact material with high stiffness and high resistance to heat deformation.

Random copolymers have a lower degree of crystallinity than homopolymers, so they have a wider melting range, greater transparency and are more resistant to impact at room temperature.

Polypropylene characteristics

Polypropylene (PP) is the thermoplastic, partially crystalline polymer obtained from the polymerization of propylene (or propene). It belongs to the polyolefin group and is used in a wide variety of applications including food packaging, textiles, laboratory equipment, automotive components and transparent films. It is highly resistant to various chemical solvents, as well as alkalis and acids. Polypropylene has good stiffness, hardness and strength, but minimal resilience. At normal temperatures, it is not susceptible to cracking, but at temperatures below 0º, embrittlement occurs. The temperature of continuous use is +5º Ca +100ºC.

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P

Polypropylene (PP) is the thermoplastic, partially crystalline polymer obtained from the polymerization of propylene (or propene). It belongs to the polyolefin group and is used in a wide variety of applications including food packaging, textiles, laboratory equipment, automotive components and transparent films. It is highly resistant to various chemical solvents, as well as alkalis and acids.

PP molecules are composed of a main chain of carbon atoms linked together, from which methyl groups (CH3-) hang on either side of the chain. When all the methyl groups are on the same side, we speak of “isotactic polypropylene”; when they are alternated on one side or the other, of “syndiotactic polypropylene”; when they have no apparent order, of “atactic polypropylene”. The properties of PP depend greatly on the type of tacticity of its molecules.

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When the percentage of ethylene exceeds a certain value, the material starts to behave like an elastomer, with properties very different from those of conventional PP. This product is called ethylene-propylene rubber (EPR).