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Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer propylene. Polypropylene belongs to the group of polyolefins and is partially crystalline and non-polar.
Therefore, the polypropylene product generally did not require additional purification steps to remove the atactic or low crystalline fraction. This meant that the APP supply from polypropylene plants using standard first- and early second-generation Z-N catalysts decreased as commercial plants adopted the new catalysts.
All polymers (amorphous or semi-crystalline) go through glass transitions. The glass-transition temperature ( T g ) is a crucial physical parameter for polymer manufacturing, processing, and use. Below T g , molecular motions are frozen and polymers are brittle and glassy.
The word plastic derives from the Greek πλαστικός (plastikos), meaning "capable of being shaped or molded;" in turn, it is from πλαστός (plastos) meaning "molded." [ 8 ] As a noun , the word most commonly refers to the solid products of petrochemical-derived manufacturing.
For example, atactic polypropylene is usually amorphous and transparent while syndiotactic polypropylene, which has crystallinity ~50%, is opaque. [30] Crystallinity also affects dyeing of polymers: crystalline polymers are more difficult to stain than amorphous ones because the dye molecules penetrate through amorphous regions with greater ease.
The Oxford Word of the Year for 2023 was rizz, understood as short for "charisma" Natalie Neysa Alund is a senior reporter for USA TODAY. Reach her at nalund@usatoday.com and follow her on X ...
JEPQ data by YCharts.. Long-term dividend yields. The monthly payouts added up to $5.38 per share over the last year, or a 10.7% yield against the current share price of approximately $58.
In condensed matter physics and materials science, an amorphous solid (or non-crystalline solid) is a solid that lacks the long-range order that is characteristic of a crystal. The terms " glass " and "glassy solid" are sometimes used synonymously with amorphous solid; however, these terms refer specifically to amorphous materials that undergo ...