Process for producing fluorubber of wide-molecular weight distribution

A wide molecular weight, fluororubber technology, applied in the field of wide molecular weight distribution fluororubber polymerization, can solve the problems of poor processing performance of special products, poor physical and mechanical properties of vulcanized rubber, power consumption, increased labor costs, etc., to achieve control of molecular structure and The effects of molecular weight distribution, guaranteed processing and application performance, and easy control of the polymerization process

Active Publication Date: 2011-09-28
SHANDONG HUAXIA SHENZHOU NEW MATERIAL
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the structure of fluororubber, it also brings disadvantages, such as poor processability, poor rheological properties, etc.
[0003] At present, there is a contradiction between the processing performance of raw rubber and the physical and mechanical properties of vulcanized rubber in fluorine rubber. The mold has few openings, and it is easy to produce flow marks or even cracks during vulcanization, resulting in low production efficiency, high scrap rate, increased power consumption and labor costs, and poor processing performance for special products

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

[0040] Take a 10L polymerization kettle as an example to prepare binary fluororubber. Add 7.2kg of ion-free water, 100ml of 10% sodium perfluorooctanoate solution, and 12g of dipotassium hydrogen phosphate to the cleaned polymerization kettle; evacuate and remove oxygen until the oxygen content is ≤ 30ppm; then use 25mol% hexafluoropropylene monomer The mixture prepared with 75mol% vinylidene fluoride monomer is used to increase the pressure of the polymerization tank to 2.1 MPa. When the temperature of the polymerization tank rises to 110 ° C, the prepared tert-butyl peroxide with a concentration of 30% is pumped in with a metering pump. Hydrogen peroxide 7g initiates reaction, adds the molecular weight modifier diethyl malonate of 20ml when reaction pressure drops to 0.6 of total pressure drop, and adds 30% tert-butyl hydroperoxide initiator at any time according to polymerization reaction situation, Until the remaining 0.4 pressure drop after the reaction, stop the reaction...

Embodiment 2

[0042] Take a 10L polymerization kettle as an example to prepare binary fluororubber. Add 7.2kg deionized water, 100ml10% ammonium perfluorooctanoate solution, and 12g sodium tetraborate to the cleaned polymerization kettle; evacuate and remove oxygen until the oxygen content≤30ppm is qualified; then use 20mol% hexafluoropropylene monomer and The mixture prepared by 80mol% vinylidene fluoride monomer is used to increase the pressure of the polymerization kettle to 2.1MPa. When the temperature of the polymerization kettle rises to 110°C, inject the prepared 30% dicarbonate peroxide with a metering pump. Propyl fat 7g initiates reaction, adds the molecular weight modifier dodecyl mercaptan of 15ml when reaction pressure drops to 0.4 of total pressure drop, and adds 30% isopropyl peroxydicarbonate initiator at any time according to polymerization reaction situation, Until the remaining 0.6 pressure drop after the reaction, stop the reaction. Coagulate, wash, dry, and finally kne...

Embodiment 5

[0047] By a polymerization method similar to Example 1, the difference is that the pressure is 1.0MPa, the reaction temperature is 115°C, the monomers are 30mol% tetrafluoroethylene and 70mol% propylene, and the molecular weight distribution coefficient M w / M n It is 3.1; the tensile strength is 12.9MPa; the elongation at break is 300%, the glass transition temperature of the fluororubber is -5°C, and the weight average molecular weight is 558688.

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
glass transition temperatureaaaaaaaaaa
tensile strengthaaaaaaaaaa
glass transition temperatureaaaaaaaaaa
Login to view more

Abstract

The present invention relates to wide molecular weight distributed fluororubber and a preparation method thereof, wherein the glass-transition temperature of the fluororubber is between 20 DEG C and 60 DEG C below zero. The preparation method is characterized in that organic groups are led into chain terminal groups of fluororubber, wherein the weight-average molecular weight is between 10,000 and 9,000,000; Mw / Mn is between 2.50 and 20; the tensile strength is between 13.0 and 20.0 MPa; and the maximum elongation is between 150 and 300 percent. Water is adopted as a medium and organic peroxide is adopted as an initiator, and the chemical coagulation method is utilized for coagulation, washing and dehydration. The crude fluororubber obtained has wide molecular weight distribution, good processability and application performance, high production efficiency, low rejection rate and superior processability, and is difficult to generate rill marks in the process of vulcanization; the processability of subsequent products under the condition of certain strength is maximumly improved; and hermetical and continuous production is realized. The polymer can be formed by means of die stamping, extruding, injection and so on when being processed and applied.

Description

technical field [0001] The invention relates to a method for polymerizing fluorine rubber with a wide molecular weight distribution, from which the fluorine rubber with a wide molecular weight distribution is prepared. Background technique [0002] Fluorine rubber refers to a polymer elastomer with special properties that is connected to a carbon atom in the main chain or side chain. Due to the structural characteristics of fluorine atoms in its molecule, it has excellent properties compared with other rubbers. The high temperature resistance, oil resistance and corrosion resistance of various chemicals are widely used in cutting-edge scientific and technological fields such as aviation, missiles, rockets, and space navigation. However, due to the structure of fluororubber, it also brings disadvantages, such as poor processability, poor rheological properties and so on. [0003] At present, there is a contradiction between the processing performance of raw rubber and the ph...

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 Patents(China)
IPC IPC(8): C08F214/18C08F210/06C08F216/14C08F4/34C08F2/24
Inventor 王汉利王军李文薇姬生涛张鹏于克波
Owner SHANDONG HUAXIA SHENZHOU NEW MATERIAL
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