Process for producing homogeneous polyethylene material

A polyethylene and catalyst technology, applied in chemical instruments and methods, chemical/physical processes, chemical/physical/physicochemical processes, etc., to achieve the effects of excellent mechanical properties, excellent appearance, and excellent water vapor barrier properties

Inactive Publication Date: 2001-09-05
ボレアリステクノロジーオイ +1
View PDF6 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

While this method can be used continuously to produce polyethylene with a good balance between processability and uniformity over a wide range of densities, it occasionally presents problems in the production of specialty materials with excellent uniformity

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0127] Complex preparation

[0128] 8.6g (66.4mmol) of 2-ethyl-1-hexanol is slowly added in 27.8g (33.2mmol) of 19.9wt% butyl-octylmagnesium, and the reaction temperature is kept below 35°C. This complex For catalyst preparation.

[0129] Catalyst preparation

[0130] 5.3g (5.1mmol) of the complex prepared above was slowly added to 4.7ml (5.1mmol) of 20wt% EADC, and the mixture was stirred at 25°C for 12 hours, then 0.48g (2.6mmol) of tetrachloromethane was added titanium oxide, and the mixture was stirred at 40-50°C for 1 hour, then the catalyst was washed with pentane and dried at 40-50°C for 2 hours.

[0131] The catalyst composition is: Al1.4%, Mg9.5%, Ti8.9%, Cl47.2%

[0132] test aggregation

[0133] The catalysts described above were tested during the polymerization of ethylene. Hydrogen was metered into the 3-liter autoclave from a 500ml steel cylinder, the pressure in the cylinder was dropped by 500kPa, 1.8 liters of n-pentane was introduced into the reactor and ...

Embodiment 2

[0135] The experimental setup comprising a loop reactor and a gas phase reactor was operated as follows. Ethylene, propane diluent and hydrogen were fed into the loop reactor together with a commercially available unsupported catalyst whose Available under the trade name Lynx760 from Mallinkrodt. The reactor was operated at a temperature of 95°C and a pressure of 60 bar. Produce ethylene homopolymer at a rate of 24kg per hour, and the MFR of the polymer coming out of the loop reactor 2 It is 600g / 10min. Therefore, low molecular weight fractions were prepared in a loop reactor, the density of the polymer was not measured, but previous experience indicated that a homopolymer with this MFR would have a density of about 974 kg / m 3 . The polymer slurry can be withdrawn from the reactor and passed to a separation step where the hydrocarbons are removed from the polymer. The polymer containing the active catalyst was transferred to a gas phase reactor where additional ethylene, h...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
densityaaaaaaaaaa
thicknessaaaaaaaaaa
densityaaaaaaaaaa
Login to view more

Abstract

The present invention concerns a process for producing homogeneous polyethylene materials and processes for making high density, medium density and low density films therefrom. The process involves producing a polyethylene composition in a multistage reaction sequence of successive polymerization stages in the presence of an ethylene-polymerizing catalyst system. According to the invention, the process is carried out using an unsupported catalyst having magnesium and titanium as active constituents, in at least one loop polymerization stage and at least one gas phase polymerization stage and, operated with different amounts of hydrogen and comonomers to produce a high molecular weight portion in one of the polymerization stages and a low molecular weight portion in another so as to provide a polyethylene composition with the low molecular weight part having a MFR2 of 250 g / 10 min or more. With this process it is possible to obtain homogeneous bimodal polyethylene material.

Description

field of invention [0001] The present invention relates to a process for the preparation of homogeneous polyethylene materials by polymerizing ethylene in a two-step or multi-step process, which facilitates the manufacture of films. More specifically, the present invention relates to a process comprising a loop and a gas phase reactor, wherein the material has excellent homogeneity and the polymer powder has a low amount of fines. Background of the invention [0002] A number of methods for producing bimodal polyethylene are known in the art. Processes involving two or more slurry reactors in series are known for the production of homogeneous polyethylene materials with good processability in end-use applications. However, these methods are limited in that only high densities such as higher than about 935 kg / cm can be produced 3 bimodal polyethylene. [0003] On the other hand, it is also known in the art to disclose processes using two or more gas phase reactors connecte...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C08J5/18B29C55/28C08F2/14C08F2/34C08F4/646C08F4/658C08F10/00C08F10/02C08F110/02C08L23/04C08L23/06
CPCC08F10/00C08F110/02Y10S526/901C08L23/06C08F10/02Y10S526/905C08L2205/02C08F4/651C08F4/6555C08F2/001C08L2666/04C08F2500/12C08F2500/18C08F2500/19C08F2500/02C08F2500/01C08F4/654C08F2/34B01J19/2435C08L23/04C08J5/18
Inventor 奥利·简·迈雷A·努米拉-帕卡里恩J·林德罗斯P·沃格尔T·加罗夫
Owner ボレアリステクノロジーオイ
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap