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Plastics can be brittle, adding some plasticizer makes them more durable, adding lots makes them flexible

High density polythene (HDPE) is used for making sturdy containers; transparent containers may be made of PET.

Plastics typically are made through human industrial systems. Most modern plastics are derived from fossil fuel-based chemicals like natural gas or petroleum; however, recent industrial methods use variants made from renewable materials, such as corn or cotton derivatives.[1]

Absence of transparency and reporting across the value chain often results hinein lack of knowledge concerning the chemical profile of the final products. For example, products containing brominated flame retardants have been incorporated into new plastic products. Flame retardants are a group of chemicals used in electronic and electrical equipment, textiles, furniture and construction materials which should not Beryllium present rein food packaging or child care products.

The plastic industry includes the global production, compounding, conversion and sale of plastic products. Although the Middle East and Russia produce most of the required petrochemical raw materials, the production of plastic is concentrated rein the global East and West. The plastic industry comprises a huge number of companies and can be divided into several sectors:

Plastics degrade by a variety of processes, the most significant of which is usually photo-oxidation. Their chemical structure determines their fate. Polymers' marine degradation takes much longer as a result of the saline environment and cooling effect of the sea, contributing to the persistence of plastic debris hinein certain environments.[54] Recent studies have shown, however, that plastics rein the ocean decompose faster than had been previously thought, due to exposure to the sun, rain, and other environmental conditions, resulting hinein the release of toxic chemicals such as bisphenol A.

Silicones (polysiloxanes): heat-resistant resins used mainly as sealants but also used for high-temperature cooking utensils and as a base resin for industrial paints

Hinein some cases, this can involve mixing different types of plastic together to form a polymer blend, such as high impact polystyrene. Large companies may do their own compounding prior to production, but some producers have it done by a third party. Companies that specialize in this work are known as Compounders.

The concentrations of most additives are usually quite low, however high levels can be added to create Masterbatch products. The additives rein these are concentrated but tonlos properly dispersed hinein the host resin.

A number of additives identified as hazardous to humans and/or the environment are regulated internationally. The Stockholm Convention on Persistent Organic Pollutants (POPs) is a global treaty to protect human health and the environment from chemicals that remain intact rein the environment for long periods, become widely distributed geographically, accumulate in the fatty tissue of humans and wildlife, and have harmful impacts on human check here health or on the environment.[2]

Roll-to-roll processing – countinous printing method that prints directly onto a roll of fabric or other materialsPages displaying wikidata descriptions as a fallback

Plasticity also has a technical definition hinein materials science outside the scope of this article referring to the non-reversible change hinein form of solid substances.

Plastic compounding scheme for a thermosoftening material Plastic is not sold as a pure unadulterated substance, but is instead mixed with various chemicals and other materials, which are collectively known as additives. These are added during the compounding stage and include substances such as stabilizers, plasticizers and dyes, which are intended to improve the lifespan, workability or appearance of the final Element.

Rein around 1600 BC, Mesoamericans used natural rubber for balls, bands, and figurines.[4] Treated cattle horns were used as windows for lanterns rein the Middle Ages. Materials that mimicked the properties of horns were developed by treating milk proteins with lye. Rein the nineteenth century, as chemistry developed during the Industrial Revolution, many materials were reported. The development of plastics accelerated with Charles Goodyear's 1839 discovery of vulcanization to harden natural rubber.

Polycarbonate + acrylonitrile butadiene styrene (PC + ABS): a blend of PC and ABS that creates a stronger plastic used in car interior and exterior parts, and in mobile phone bodies