Preparation method of polypropylene with high melt strength

A high melt strength, polypropylene technology, applied in the field of polypropylene preparation, can solve problems such as strong complexing ability, and achieve the effects of easy operation, broad application prospects, and high melt strength

Active Publication Date: 2014-05-14
CHINA PETROLEUM & CHEM CORP +1
View PDF19 Cites 53 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method also has the disadvantage that the first external electron donor has a strong complexing ability with the activ

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Preparation method of polypropylene with high melt strength
  • Preparation method of polypropylene with high melt strength
  • Preparation method of polypropylene with high melt strength

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0043] Example 1:

[0044] The polymerization reaction was carried out on a set of 25Kg / hr polypropylene pilot plant. Its main equipment includes a prepolymerization reactor, a first loop reactor and a second loop reactor. The polymerization method and steps are as follows:

[0045] Step ⅰ

[0046] Pre-polymerization reaction:

[0047] Main catalyst (DQ-III catalyst, provided by Sinopec Catalyst Company Beijing Aoda Branch), co-catalyst (triethylaluminum), first external electron donor (dicyclopentyldimethoxysilane) at 6℃, 20min After the pre-contact, the continuous stirred tank pre-polymerization reactor is continuously added to the pre-polymerization reactor. The flow of triethyl aluminum (TEA) entering the pre-polymerization reactor is 6.33 g / hr, dicyclopentyl dimethoxy silane The (DCPMS) flow rate is 0.63 g / hr, the main catalyst flow rate is 0.01 g / hr, and the TEA / DCPMS ratio is 20 (molar ratio), where DCPMS is the first external electron donor. The prepolymerization is carrie...

Example Embodiment

[0055] Example 2:

[0056] The steps are the same as in Example 1, except that a small amount of hydrogen is added to the first loop reactor in step i, the hydrogen concentration detected by online chromatography is 300 ppmV, and the hydrogen concentration in the second loop reactor in step iii is changed It is 1000ppmV. The polymerization process conditions, the analysis results of the obtained polymer and the physical properties of the polymer are listed in Tables 1 to 3.

Example Embodiment

[0057] Example 3:

[0058] The steps are the same as in Example 2, except that the ratio of aluminum alkyl to external electron donor in the two steps is adjusted, and the TEA / DCPMS in the first reactor of step i is adjusted to 60 (molar ratio ), the TEA / DIBMP in the second reactor is adjusted to 10 (molar ratio), and the hydrogen concentration in the second loop reactor in step iii is changed to 5000 ppmV. The polymerization process conditions, the analysis results of the obtained polymer and the physical properties of the polymer are listed in Tables 1 to 3.

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

No PUM Login to view more

Abstract

The invention discloses a preparation method of polypropylene with high melt strength. The method includes i) a step of, under the action of a Ziegler-Natta catalyst containing a silane type external electron donor, subjecting propylene or propylene with other alpha-olefin to polymerization to obtain a polymer A having a melt mass flow rate of 0.01-0.4 g/min, with a hydrogen concentration being not more than 400 ppmV; ii) a step of adding a 1,3-diether type external electron donor and premixing the 1,3-diether type external electron donor and the polymer A; iii) a step of, under the existence of hydrogen and the premixed materials in the step ii), subjecting the propylene or the propylene with other alpha-olefin to polymerization to obtain a polymer B having a melt mass flow rate of 1.0-60 g/10min; and a step of preparing polypropylene C with high melt strength comprising the polymer A and the polymer B. The melt mass flow rate of the polypropylene C is 0.8-15 g/10min. The preparation method is simple and feasible and is convenient to operate and prone to industrial production. High-performance products with high melt strength and wide molecular weight distribution can be prepared by the method. The method has wide application prospect.

Description

technical field [0001] The invention relates to a method for preparing polypropylene, in particular to a method for preparing polypropylene with wide molecular weight distribution and high melt strength. Background technique [0002] Due to its high melt strength, yield strength, flexural modulus, heat distortion temperature, melting point, crystallization temperature and short crystallization time, high melt strength polypropylene is widely used in thermoforming, foaming, extrusion coating and other fields. Has been widely used. In these applications, the use of high melt strength polypropylene for thermoforming can make the parts demould at a higher temperature, shorten the molding cycle, and increase the output; Bubble magnification, reduce density, increase closed cell ratio; exhibit faster coating speed and small necking during extrusion coating. Therefore, high melt strength polypropylene is the research focus of polypropylene production technology innovation. The s...

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
IPC IPC(8): C08F110/06C08F210/06C08F4/646C08F4/649
Inventor 宋文波毕福勇张晓萌魏文骏郭梅芳张师军
Owner CHINA PETROLEUM & CHEM CORP
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