JPS6046123B2 - Fluorine-containing copolymer and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention describes novel polymers of tetrafluoroethylene and α
-Relating to a copolymer with β/β-trifluorostyrene and a method for producing the same.

Tetrafluoroethylene (hereinafter referred to as TFE) and α
・β・β-Trifluorostyrene (hereinafter referred to as TFS)
Each individual polymer is known.

TFE polymers are typical among fluororesins and are widely used because of their extremely excellent heat resistance, chemical resistance, and electrical properties. On the other hand, TFE polymer is not as widely used as the former, but its manufacturing method and polymer properties are known, and as a polymer it has a high softening temperature (approximately 240°C) and good electrical properties. It has the following characteristics. It is also known that sulfonated products are used as heat-resistant ion exchange resins. However, sulfonated TFS polymers have poor flexibility and have many practical problems when used as ion exchange membranes. The present inventors have focused on the property that the phenyl group of TFS can be substituted with various functional groups by sulfonation, amination, etc., and that the substituted products are expected to have various useful applications. T that does not reduce flexibility
The present invention was completed by attempting to produce a fluorine-containing copolymer containing an FS component.

The present invention contains repeating units represented by formula: (CF2CF2) and in proportions of 5 to 95 mol% and 95 to 5 mol%, respectively, and has an intrinsic viscosity of at least about 0.1d11f measured as a methyl ethyl ketone solution at 35°C. The present invention relates to a copolymer characterized by: and a method for producing the same.

The copolymer of TFE and TFS of the present invention is a new polymer that has high chemical resistance, high heat resistance, and excellent flexibility. Even if introduced, the physical properties will not be deteriorated.

The content of TFE component in the copolymer according to the present invention is 5 to 9
5 mol% is preferred.

This copolymer can be produced by including 25 to 99 mol % of TFE in the polymerization system and polymerizing using a radical polymerization initiation source. The copolymers of the present invention have an intrinsic viscosity of at least about 0.1 d1'y, measured as a solution in methyl ethyl ketone at 35°C.

If the intrinsic viscosity is lower than this, the copolymer will have a low molecular weight and poor shape retention, and the molded product will be brittle and impractical. The TFE-TFS copolymer of the present invention has a content ratio of TFE. If TF is high, the crystallinity is relatively high, and conversely
When the S content is high, the crystallinity decreases, resulting in an amorphous polymer. A particularly remarkable property of this polymer is that its second-order transition temperature (Tg) becomes very high when the TFS content is relatively high. For example, as shown in Example 4, TFS
The secondary transition point of the copolymer with a content of 90.7 mol% is 180
℃, which is at the highest level compared to known polymers. This copolymer also has a thermal decomposition temperature of 350 to 450°C.
Therefore, it has excellent moldability. Furthermore, this copolymer is thermoplastic in nature;
Unlike the homopolymer E, it can be molded by any method such as extrusion, injection, compression, etc. by heating and melting. Furthermore, it can be dissolved in organic solvents such as acetone, methyl ethyl ketone, chloroform, benzene, toluene, etc., and therefore can be used as a coating material or film material. Substituents such as sulfone groups and amino groups can be introduced into the phenyl group in the molecule by conventional methods, making it possible to synthesize various derivatives. It can be used as a heat-resistant ion exchange membrane, which was previously impossible. The copolymer of the present invention is TFE and T
FS can be produced by mixing each monomer and using a known radical polymerization initiation source.

The radical polymerization initiation source refers to redox polymerization methods using inorganic or organic peroxides, methods using ionizing radiation, and the like. Polymerization may be carried out by suspension polymerization or emulsion polymerization using water as a medium. Polymerization temperature is O~80℃, pressure 5~300℃
A range of k91cIt is appropriate. Example 1 TF in a stainless steel autoclave with an internal volume of 100 m1
'Sl6yl(NH4)2S2080.1g, NaHS
O3O. O5 da, Cl2H25NH2・HCll. 45
Add f and 50y of water.

The autoclave was then sealed, cooled with dry ice, evacuated, and TFEl. Add 5y. Adjust the internal temperature to 40°C and shake for 2 minutes. Methanol is added to the reaction product to coagulate the resulting polymer. The precipitate was dissolved in chloroform and poured into methanol to obtain a precipitated purified powdery polymer 2.2f. The physical properties of this purified polymer are shown below.
Shown in 1. From the elemental analysis values, the molar ratio of the produced polymer is TFS
:'IFE=90.7:9.3. This copolymer is dissolved in acetone, cast on a glass plate, and the acetone is evaporated to yield a transparent, rigid film.
Example 2 TF'S was placed in a stainless steel autoclave with an internal volume of 2e.
l6fl. ．． FeSO4.7H202.4y1 ascorbic acid 12y1 sodium lauryl sulfate 10y and water 500y are charged.

Seal the autoclave and add 25 Oy of TFE. Adjust the internal temperature to 0~5℃ and add hydrogen peroxide solution (
Add 50 ml of 3%) over 24 hours using a metering pump. The polymerization liquid was taken out from the autoclave, and the copolymer was purified in the same manner as in Example 1 to obtain powdered copolymer 3q. The elemental analysis values of this copolymer are F: 46.1% by weight, C
:51. The weight percentage, H: was 2.25% by weight. The composition of the copolymer calculated from this is TFS:TFE=64:3
The molar ratio is 6. Also, the limiting viscosity [η] is 0.15d11
y (35°C, in MEK). Similar to the copolymer of Example 1, a transparent film can be obtained from this copolymer from an acetone solution. Example 3 Reaction time was 4 using TFS16y and TFE8OOy.
Copolymerization was carried out in the same manner as in Example 2 except that the heating time was 8 hours.

Claims (1)

[Claims] 1 Contains repeating units represented by formula: (CF_2CF_2) and formula: ▲Mathematical formula, chemical formula, table, etc.▼ in proportions of 5 to 95 mol% and 95 to 5 mol%, respectively, A copolymer having an intrinsic viscosity of at least about 0.1 dl/g, measured as a solution in methyl ethyl ketone at 35°C. 2 Formula: (CF_2CF_2) and formula: ▲Mathematical formula, chemical formula, table, etc., which are characterized by copolymerizing tetrafluoroethylene and α, β, β-trifluorostyrene using a radical polymerization initiation source. A copolymer containing repeating units represented by 5 to 95 mol% and 95 to 5 mol%, respectively, and having an intrinsic viscosity of at least about 0.1 dl/g as measured as a methyl ethyl ketone solution at 35°C. Production method.