Translations in context of "polietilen tereftalat" in Romanian-English from Reverso Context: PET este o peliculă din polietilen tereftalat fără proprietăți. SOL-JEL YÖNTEMİ İLE DÜŞÜK SICAKLIKTA POLİETİLEN TEREFTALAT DOKUSUZ YÜZEY KUMAŞLARIN İNDİYUM ÇİNKO OKSİT ÇÖZELTİLER İLE. English Turkish online dictionary Tureng, translate words and terms with different pronunciation options. expandable braided polyethylene terephthalate textile.
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Tureng - polietilen-tereftalat - Turkish English Dictionary
It can be colored during processing. Replacing terephthalic acid right with isophthalic acid center creates a kink in the PET chain, interfering with crystallization and lowering polietilen tereftalat polymer's melting point.
Another common modifier is isophthalic acidreplacing some of the 1,4- para- linked terephthalate units. The 1,2- ortho- or 1,3- meta - linkage polietilen tereftalat an angle in the chain, which also disturbs crystallinity.
Polietilen tereftalat - Translation into English - examples Romanian | Reverso Context
On the other polietilen tereftalat, crystallization is important in other applications where mechanical and dimensional stability are important, such as seat belts. As a result, bottles are obtainable via stretch blow molding "SBM"which are polietilen tereftalat clear and crystalline enough to be an adequate barrier to aromas and even gases, such as carbon dioxide in carbonated beverages.
Methanol CH3OH is removed by distillation to drive the reaction forward. Polietilen tereftalat ethylene glycol is distilled off at higher temperature with the aid of vacuum.
Water is eliminated in the reaction, and it is also continuously removed by distillation: The main degradations that can occur are hydrolytic, and probably most important, thermal oxidation. When PET degrades, several things happen: Discoloration is due to the formation of polietilen tereftalat chromophoric systems following prolonged thermal treatment at elevated temperatures.
This becomes a problem when the polietilen tereftalat requirements of the polymer are very high, such as in packaging applications. The thermal and thermooxidative degradation results in poor processibility characteristics and performance of the material.
One way to alleviate this is to use a copolymer.
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Comonomers such as CHDM or isophthalic acid lower the melting temperature and reduce the degree of crystallinity of PET especially important when the material is used for bottle manufacturing.
This helps to prevent degradation, reducing the acetaldehyde content of the finished product to an acceptable that is, unnoticeable level.
See copolymersabove. Another way to improve the stability of the polietilen tereftalat is to use stabilizers, mainly antioxidants such as phosphites. Recently, molecular level stabilization of the material using nanostructured chemicals has also been considered.
Acetaldehyde[ edit ] Acetaldehyde is a colorless, volatile substance with a fruity smell. Although it forms naturally in some fruit, it can cause an polietilen tereftalat in bottled water.
Acetaldehyde forms by polietilen tereftalat of PET through the mishandling of the material.
When acetaldehyde is produced, some of it remains dissolved in the walls polietilen tereftalat a container and then polietilen tereftalat into the product stored inside, altering the taste and aroma.
This is not such a problem for non-consumables such as shampoofor fruit juices which already contain acetaldehydeor for strong-tasting drinks like soft drinks.
For bottled water, however, low acetaldehyde content is quite important, because, if nothing masks the aroma, even extremely low concentrations 10—20 parts per billion in the water of polietilen tereftalat can produce an off-taste.
Antimony[ edit ] Antimony Sb is a metalloid element that is used as a catalyst polietilen tereftalat the form of compounds such as antimony trioxide Polietilen tereftalat or antimony triacetate in the production of PET.
After manufacturing, a detectable amount of antimony can be found on the surface of the product. This residue can be removed with washing.