Preparing method of tetrafluoroethylene-hexafluoropropylene copolymer concentrated dispersion liquid

A polyperfluoroethylene propylene and dispersion technology, applied in the chemical industry, can solve the problems of easy carbonization of emulsifiers, thick coating film, poor gloss, etc., and achieve the effects of simple process, strong operability and high concentration efficiency

Active Publication Date: 2014-10-29
CHENGUANG RES INST OF CHEM IND
View PDF3 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

But because it contains benzene ring in its molecule, therefore, there are following problems in application: (1) emulsion surface tension is big, can not form the thick coating film of coating during processing; Formed coating film is easy to crack, and glossiness is poor; (2) It is easy to decompose in the sintering process, releasing harmful atmospheric gases, such as benzene, xylene, etc.; (3) The emulsifier is easy to decompose incompletely during the sintering process, and the residual emulsifier is easy to carbonize, which aff

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

Example Embodiment

[0030] Example 1 Preparation method of polyperfluoroethylene propylene concentrated dispersion

[0031] The batch free radical emulsion preparation was carried out in a 50L autoclave to prepare polyperfluoroethylene propylene resin.

[0032] Add 30L of ion-free water to the reaction kettle, raise the temperature to boil, and keep the temperature constant for 80 minutes. The air in the vapor space in the reactor is first replaced with nitrogen to an oxygen content of 20 ppm. Add 60g50g / L ammonium perfluorooctanoate aqueous solution to the reaction kettle through a metering pump, and raise the temperature of the reaction kettle to 85°C. Add 4.5Kg of initial mixed monomer (0.9kg tetrafluoroethylene and 3.6kg perfluoropropylene) within 5min. Turn on the stirring, fully mix the mixed monomers in the reactor, and then add 30g50g / L potassium persulfate solution to start the reaction. During the reaction process, additional mixed monomers (tetrafluoroethylene:perfluoropropylene=15:1, mo...

Example Embodiment

[0035] Example 2 Preparation method of polyperfluoroethylene propylene concentrated dispersion

[0036] Take 2kg of the emulsion prepared in Example 1, filter to remove the demulsifier and other impurities in the emulsion, add it to a 3L round bottom flask; add 0.23g of metal chelating agent hydroxyethylethylenediaminetriacetic acid (HEDTA), and start stirring Mix well, then let stand for 40min; turn on the stirring, slowly add 35g fatty acid polyoxyethylene emulsifier (H(CH 2 ) 11 COO(CH 2 CH 2 O) 9 H), after mixing uniformly, stop stirring; turn on the vacuum system and temperature control system, set the vacuum degree to 0.075MPa, and the temperature to 65°C; after about 3 hours of heating and concentration under reduced pressure, the specific gravity of the emulsion reaches 1.390, stop the vacuum With temperature control system, the emulsion is released; the pH value of the concentrated dispersion is adjusted to 9 with ammonia water.

[0037] Sample delivery test results: The s...

Example Embodiment

[0038] Example 3 Preparation method of polyperfluoroethylene propylene concentrated dispersion

[0039] Take 2kg of the emulsion prepared in Example 1, remove the demulsifier and other impurities in the emulsion by filtration, and add it to a 3L round-bottom flask; add 0.22g of a metal chelating agent citric acid (CA) and glycolic acid compound (mass The ratio is 1:1), start to stir and mix evenly, then let it stand for 40 minutes; turn on the stirring, slowly add 25g fatty acid polyoxyethylene emulsifier (H(CH 2 ) 11 COO(CH 2 CH 2 O) 9 H), after mixing uniformly, stop stirring; turn on the vacuum system and temperature control system, set the vacuum degree to 0.075MPa, and the temperature to 65℃; after about 3 hours of heating and concentration under reduced pressure, the specific gravity of the emulsion reaches 1.405, stop the vacuum With temperature control system, the emulsion is released; the pH value of the concentrated dispersion is adjusted to 9 with ammonia water.

[0040]...

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
Particle sizeaaaaaaaaaa
Particle sizeaaaaaaaaaa
Particle sizeaaaaaaaaaa
Login to view more

Abstract

A preparing method of a tetrafluoroethylene-hexafluoropropylene copolymer concentrated dispersion liquid is provided. The method includes: adding polyoxyethylene aliphatate and a metal chelating agent into an aqueous polymerization solution of tetrafluoroethylene-hexafluoropropylene copolymer, mixing uniformly, heating, concentrating under vacuum until the solid content is 30-70 wt%, and adding a pH conditioning agent into the concentrated dispersion liquid to adjust the pH value of the dispersion liquid to 5-10, then a finished product of the tetrafluoroethylene-hexafluoropropylene copolymer concentrated dispersion liquid is obtained. The product is free of floating substances and color changes after the product is allowed to stand for 6 months. The stability of the product can be higher than 300 s. The method has characteristics of simple process, high operability and high concentration efficiency, and is environmental friendly and suitable for industrial production.

Description

technical field [0001] The invention relates to the field of chemical industry, in particular to a method for preparing a concentrated dispersion of polyperfluoroethylene propylene. Background technique [0002] Polyfluoroethylene propylene (FEP) is a copolymer of tetrafluoroethylene (TFE) and perfluoropropylene (HFP), its molecular structure is equivalent to a part of the fluorine atoms on the molecular chain of polytetrafluoroethylene (PTFE) The structure formed after group substitution. It has excellent properties similar to polytetrafluoroethylene, and has the characteristics of thermoplastic molding. Except that the use temperature is lower than that of polytetrafluoroethylene, other properties such as corrosion resistance, electrical properties and physical and mechanical properties are similar to polytetrafluoroethylene. . It is widely used in electronics, electrical, chemical and chemical industries, especially in the preparation of high-performance, high-quality w...

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): C08J3/07C08L27/12C08L27/18
Inventor 兰军张建新李斌张廷健余金龙王先荣赵少春赵媛媛常映军
Owner CHENGUANG RES INST OF CHEM IND
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