CN-116897174-B - Fluorine-containing copolymer

Abstract

The present invention provides a fluorine-containing copolymer comprising tetrafluoroethylene units, hexafluoropropylene units and perfluoro (propyl vinyl ether) units, wherein the content of hexafluoropropylene units is 7.0 to 8.5 mass% relative to the total monomer units, the content of perfluoro (propyl vinyl ether) units is 1.5 to 2.9 mass% relative to the total monomer units, and the melt flow rate at 372 ℃ is 9g/10 min to 15g/10 min.

Inventors

• Jing Banzhongqing
• YAMAMOTO YUKARI
• Kind family helps U.S.

Assignees

• 大金工业株式会社

Dates

Publication Date

20260512

Application Date

20220228

Priority Date

20210226

Claims (8)

1. 1. A fluorine-containing copolymer comprising tetrafluoroethylene units, hexafluoropropylene units, perfluoro (propyl vinyl ether) units and other monomer units, wherein, The content of tetrafluoroethylene unit is 88.6 to 91.5 mass% relative to the total monomer units, The content of hexafluoropropylene units is 7.0 to 8.5 mass% relative to the total monomer units, The content of perfluoro (propyl vinyl ether) units is 1.5 to 2.9 mass% relative to the total monomer units, The content of other monomer units is 0 to 2.9 mass% relative to the total monomer units, Wherein the total content of tetrafluoroethylene unit, hexafluoropropylene unit, perfluoro (propyl vinyl ether) unit and other monomer unit is 100% by mass, The melt flow rate at 372 ℃ is 9g/10 min-15 g/10 min.
2. 2. The fluorocopolymer as described in claim 1, wherein the content of hexafluoropropylene units is 7.2% by mass to 8.1% by mass based on the total monomer units.
3. 3. The fluorocopolymer as claimed in claim 1 or 2, wherein the content of perfluoro (propyl vinyl ether) units is 1.7% by mass to 2.2% by mass with respect to the total monomer units.
4. 4. The fluorocopolymer as claimed in claim 1 or 2, wherein the melt flow rate at 372 ℃ is from 10g/10 min to 14g/10 min.
5. 5. The fluorocopolymer as claimed in claim 1 or 2, wherein the number of functional groups of-cf=cf 2 、-CF 2 H、-COF、-COOH、-COOCH 3 、-CONH 2 and-CH 2 OH is 90 or less per 10 6 main chain carbon atoms.
6. 6. An injection molded article comprising the fluorocopolymer as defined in any one of claims 1 to 5.
7. 7. A coated electric wire comprising a coating layer comprising the fluorocopolymer as defined in any one of claims 1 to 5.
8. 8. A molded article comprising the fluorocopolymer as defined in any one of claims 1 to 5, wherein the molded article is a valve, a joint, a flowmeter, a wire coating or a film.

Description

Fluorine-containing copolymer Technical Field The present invention relates to a fluorine-containing copolymer. Background Patent document 1 describes a terpolymer containing (a) tetrafluoroethylene, (b) hexafluoropropylene in an amount of about 4 to about 12 wt% based on the weight of the terpolymer, and (c) perfluoro (ethyl vinyl ether) or perfluoro (n-propyl vinyl ether) in an amount of about 0.5 to about 3 wt% based on the weight of the terpolymer, in a copolymerized form. Prior art literature Patent literature Patent document 1 Japanese patent laid-open No. 52-109588 Disclosure of Invention Problems to be solved by the invention The purpose of the present invention is to provide a fluorocopolymer which can be molded at a high injection rate by an injection molding method to give an injection molded article having a beautiful appearance, which can be formed at a high rate by an extrusion molding method to give a thin coating layer on a core wire having a small diameter, which can be molded at a high molding rate by an extrusion molding method to give a film having a uniform thickness, and which can give a molded article having excellent wear resistance at 50 ℃, low hydrogen permeability, rigidity at 75 ℃ at a high temperature, tensile creep resistance at 140 ℃ and solvent crack resistance. Means for solving the problems According to the present invention, there is provided a fluorine-containing copolymer comprising tetrafluoroethylene units, hexafluoropropylene units and perfluoro (propyl vinyl ether) units, wherein the content of hexafluoropropylene units is 7.0 to 8.5% by mass relative to the total monomer units, the content of perfluoro (propyl vinyl ether) units is 1.5 to 2.9% by mass relative to the total monomer units, and the melt flow rate at 372 ℃ is 9g/10 min to 15g/10 min. The content of hexafluoropropylene units is preferably 7.2 mass% to 8.1 mass% relative to the total monomer units. The content of perfluoro (propyl vinyl ether) unit is preferably 1.7 to 2.2 mass% with respect to the total monomer units. The melt flow rate at 372℃is preferably 10g/10 min to 14g/10 min. The number of functional groups is preferably 90 or less per 10 6 main chain carbon atoms. Further, according to the present invention, there is provided an injection molded article comprising the above-mentioned fluorocopolymer. Further, according to the present invention, there is provided a coated electric wire comprising a coating layer containing the fluorocopolymer. Further, according to the present invention, there is provided a molded article comprising the above-mentioned fluorocopolymer, wherein the molded article is a valve, a joint, a flowmeter, a wire coating or a film. ADVANTAGEOUS EFFECTS OF INVENTION According to the present invention, it is possible to provide a fluorocopolymer which can be molded at a high injection speed by injection molding to obtain an excellent injection molded article, which can be formed by extrusion molding to form a thin coating layer on a core wire having a small diameter at a high speed, which can be molded at a high molding speed to obtain a film having a uniform thickness by extrusion molding, and which can give a molded article excellent in 50 ℃. Detailed Description Hereinafter, specific embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments. The fluorocopolymer of the present invention comprises Tetrafluoroethylene (TFE) units, hexafluoropropylene (HFP) units and perfluoro (propyl vinyl ether) (PPVE) units. As the fluororesin, a non-melt-processible fluororesin such as Polytetrafluoroethylene (PTFE) and a melt-processible fluororesin are known. PTFE has excellent properties, but has the disadvantage of being extremely difficult to melt process. On the other hand, as melt-processible fluororesin, TFE/HFP copolymer (FEP), TFE/PPVE copolymer (PFA) and the like are known, but have a disadvantage of inferior heat resistance and the like to PTFE. Accordingly, patent document 1 proposes the above-mentioned terpolymer as a fluorocarbon polymer which improves these drawbacks. However, there is a need for a fluorocopolymer which gives a molded article excellent in moldability, abrasion resistance at 50 ℃, hydrogen permeability at 75 ℃ and rigidity at high temperature, tensile creep resistance at 140 ℃ and solvent crack resistance as compared with conventional copolymers. For example, valves for controlling the pressure and flow rate of fluids such as chemical solutions are required to have high-temperature abrasion resistance, high-temperature rigidity, and tensile creep resistance so as not to be damaged by friction, tensile stress, load, and the like generated when the valves are opened and closed. Further, such a valve has a complicated structure having a thin wall portion, and thus a good moldability is also required for the copolymer. It has been found that by adjusting the content of HFP units and PPV