“Ziegler process”的概念、定义、翻译、参考文献-科学参考

Ziegler process

Chemistry

An industrial process for the manufacture of high-density polyethene using catalysts of titanium(IV) chloride (TiCl₄) and aluminium alkyls (e.g. triethylaluminium, Al(C₂H₅)₃). The process was introduced in 1953 by the German chemist Karl Ziegler (1898–1973). It allowed the manufacture of polythene at lower temperatures (about 60°C) and pressures (about 1 atm.) than used in the original process. Moreover, the polyethene produced had more straight-chain molecules, giving the product more rigidity and a higher melting point than the earlier low-density polyethene. The reaction involves the formation of a titanium alkyl in which the titanium can coordinate directly to the pi bond in ethene.
In 1954 the process was developed further by the Italian chemist Giulio Natta (1903–79), who extended the use of Ziegler’s catalysts (and similar catalysts) to other alkenes. In particular he showed how to produce stereospecific polymers of propene.

Chemical Engineering

1. A process used for the manufacture of high-density polyethylene using catalysts known as Ziegler–Natta catalysts. First introduced in 1953, they improved on the original manufacturing process and were able to use a lower temperature of 60^ºC and pressure of around one atmosphere. They are named after German chemist Karl Waldemar Ziegler (1898–1973) and the Italian chemist Giulio Natta (1903–79) who developed the process further in 1954 for the use with other alkenes. They were awarded the Nobel Prize in Chemistry in 1963.

2. A process used for the production of tetraethyl lead by electrolyzing a molten complex of ethyl potassium with triethyl aluminium. It was invented by Karl Waldemar Ziegler (1898–1973) in 1963.

单词	Ziegler process
释义	Ziegler process Chemistry An industrial process for the manufacture of high-density polyethene using catalysts of titanium(IV) chloride (TiCl₄) and aluminium alkyls (e.g. triethylaluminium, Al(C₂H₅)₃). The process was introduced in 1953 by the German chemist Karl Ziegler (1898–1973). It allowed the manufacture of polythene at lower temperatures (about 60°C) and pressures (about 1 atm.) than used in the original process. Moreover, the polyethene produced had more straight-chain molecules, giving the product more rigidity and a higher melting point than the earlier low-density polyethene. The reaction involves the formation of a titanium alkyl in which the titanium can coordinate directly to the pi bond in ethene. In 1954 the process was developed further by the Italian chemist Giulio Natta (1903–79), who extended the use of Ziegler’s catalysts (and similar catalysts) to other alkenes. In particular he showed how to produce stereospecific polymers of propene. Chemical Engineering 1. A process used for the manufacture of high-density polyethylene using catalysts known as Ziegler–Natta catalysts. First introduced in 1953, they improved on the original manufacturing process and were able to use a lower temperature of 60^ºC and pressure of around one atmosphere. They are named after German chemist Karl Waldemar Ziegler (1898–1973) and the Italian chemist Giulio Natta (1903–79) who developed the process further in 1954 for the use with other alkenes. They were awarded the Nobel Prize in Chemistry in 1963. 2. A process used for the production of tetraethyl lead by electrolyzing a molten complex of ethyl potassium with triethyl aluminium. It was invented by Karl Waldemar Ziegler (1898–1973) in 1963.
随便看	lithium oxide lithium star lithium sulphate lithium tetrahydroaluminate(III) litho- lithoclast lithofacies lithofacies map lithography lithologic symbol lithologic trap lithology lithology classification lithomarge lithomorphic soil lithophile lithophysae lithosequence lithosiderite lithosome lithosphere lithospheric plate lithostatic stress lithostratigraphic unit lithostratigraphy