RU2287000C1 - Fluoroplastic lacquer for coating - Google Patents

Abstract

FIELD: lacquers.

SUBSTANCE: invention relates to fluoroplastic lacquer based on soluble fluoropolymers designated for coating different surfaces. Lacquer comprises copolymer of tetrafluoroethylene with vinylidene fluoride (F-42L) as a fluoropolymer dissolved in acetone as an organic solvent and comprises additionally ethyl acetate in the following ratio of components, wt.-%: copolymer of tetrafluoroethylene with vinylidene fluoride, 10-20; acetone, 60-80; ethyl acetate, 10-20. Invention provides improving exploitation and consumer properties of lacquer and to expand the field of its using.

EFFECT: improved and valuable properties of lacquer.

4 cl, 1 tbl

Description

The invention relates to organic chemistry, in particular to fluoroplastic varnishes based on soluble fluoroolefins, intended for coating various surfaces: metals, concrete, wood, fabrics, plastics, etc. to protect them from exposure to water and aggressive environments.

Known fluoroplastic varnishes, primers and enamels based on them, containing copolymers of fluoroolefins, soluble in a mixture of esters or ketones with aromatic hydrocarbons, which are used to protect components and products for various purposes, operated in any climatic zone under the influence of water and aggressive environments. These varnishes are used for applying on top of coatings based on other film-forming materials, for example polyacrylates, with the aim of hydrophobizing them and increasing the weather resistance (Chemical Encyclopedic Dictionary, M .: Soviet Encyclopedia, 1983, p.639). The main disadvantage of the known fluoroplastic varnishes is their lack of adhesion to the substrate.

Fluoroplastic varnishes are known, as well as primers and enamels based on them, containing soluble copolymers of trifluorochlorethylene with alkyl vinyl and hydroxyalkyl vinyl ethers in an organic solvent - xylene (LPR varnish), used to protect metal, plastic, concrete and other surfaces exposed to atmospheric influences in construction, auto, ship, car building, in the chemical industry (SU 2066328, class C 08 F 214/24, publ. 1996; SU 2088600, class C 08 F 214/24, publ. 1997; SU 2208018 Cl. C 08 F 214/24, 127/12, publ. 2003; SU 2209215, cl. 08 F 214/24, 127/12, publ. 2003). The disadvantage of these known varnishes containing trifluorochlorethylene copolymers is the use of 100% xylene with a maximum concentration limit of 50 mg / m ³ as an organic solvent for the fluoropolymer, which poses a sufficient danger to personnel working with varnishes and reduces its consumer properties (Karjakina MI, Poptsov VE Technology of polymer coatings, M .: Chemistry, 1983, p.15).

Known fluoroplastic varnishes containing a copolymer of trifluorochloroethylene with vinylidene fluoride (F-32L), dissolved in a mixture of esters or ketones with aromatic hydrocarbons, from which coatings are obtained, characterized by low moisture permeability, high water and weather resistance; thermal and frost resistance. The lack of varnishes containing the F-32L copolymer is the use of toluene in the composition of the organic solvent, which has a high MPC of 50 mg / m ³ , which poses a danger to personnel working with varnishes and reduces its consumer properties. In addition, the well-known fluoroplastic varnish F-32L has insufficient adhesion to the substrate. Weak adhesion to metals does not allow to obtain products with high performance characteristics. The composition and specific properties of the varnish are not given. (Chemical Encyclopedic Dictionary, M .: Soviet Encyclopedia, 1983, p.639; Encyclopedia of Polymers, M .: Soviet Encyclopedia, 1972, v.3, p.797).

The closest composition to the proposed varnish is a known composition that can be used to coat various surfaces, containing a copolymer of tetrafluoroethylene with vinylidene fluoride (F-42L), dissolved in an organic solvent - acetone with a ratio of components, wt.%:

tetrafluoroethylene copolymer with vinylidene fluoride 5-20 acetone 80-95

(see Morozova NI and others. The phase state and mechanical properties of compositions based on solutions of a copolymer of tetrafluoroethylene with vinylidene fluoride, Colloid Journal, 1988, Volume 50, Issue 4, pp. 698-702).

A disadvantage of the known composition containing the F-42L copolymer is the use of 100% acetone in the organic solvent, which has high volatility, low boiling point and flash point, which is dangerous for personnel working with the composition and reduces its consumer properties. The known composition based on only acetone has insufficient adhesion to the substrate. Weak adhesion to metals does not allow to obtain products with high performance characteristics. In addition, obtaining from it multilayer coatings up to 200 microns is complicated. When applying a large number of layers, the coating wrinkles, small cracks, gels and irregularities are formed on it, which also reduces the quality of the products.

The technical result, the achievement of which the present invention provides, is to improve the operational and consumer properties of the fluoroplastic varnish based on soluble fluoropolymers of a copolymer of tetrafluoroethylene with vinylidene fluoride, in expanding the scope of its application.

The specified technical result is achieved in that a fluoroplastic varnish based on soluble fluoropolymers intended for coating various surfaces, which as a fluoropolymer contains a copolymer of tetrafluoroethylene with vinylidene fluoride (F-42L), dissolved in an organic solvent - acetone, additionally contains ethyl acetate in the following ratio of components, wt.%:

tetrafluoroethylene copolymer with vinylidene fluoride 10-20 acetone 60-80 ethyl acetate 10-20

The fluoroplastic varnish additionally contains a mixture of amyl acetate and cyclohexanone in the following ratio of components, wt.%:

tetrafluoroethylene copolymer with vinylidene fluoride 5-10 acetone 10-20 ethyl acetate 30-35 amyl acetate 30-35 cyclohexanone 10-15

Ftoroplastovy varnish additionally contains a diluent - ethyl cellosolve in the following ratio of components, wt.%:

tetrafluoroethylene copolymer with vinylidene fluoride 5-20 acetone 10-15 ethyl acetate 25-30 amyl acetate 25-30 cyclohexanone 5-10 ethyl cellosolve 10-15

Ftoroplastovy varnish in the following ratio of components, wt.%:

tetrafluoroethylene copolymer with vinylidene fluoride 5-15 acetone 35-50 ethyl acetate 25-30 cyclohexanone 5-10 ethyl cellosolve 10-15

Lacquer based on acetone and a mixture of solvents is suitable for forming fibers, for casting film, coating fiberglass, fabrics, metals and other materials.

The method was tested in laboratory conditions.

To prepare the varnish, take a copolymer of tetrafluoroethylene with vinylidene fluoride grade F-42L and dissolve at 40-50 ° C in an appropriate mixture of the following solvents: acetone, ethyl acetate, amyl acetate, cyclohexanone. All components are added within the claimed limits sequentially with stirring until completely dissolved. If necessary, a diluent, ethyl cellosolve, is added at the end.

The proposed compositions of fluoroplastic varnish for coatings are shown in the table (examples 1-8).

From the varnishes presented in the table, coatings are prepared.

The varnish coating is obtained by irrigation on a 100 × 100 mm size aluminum foil defatted in a 10% sodium hydroxide solution and dried at room temperature. The properties of varnishes and coatings obtained from them are determined by standard methods:

- conditional viscosity on a viscometer B3-246 according to GOST 8420-74;

- adhesion - by the method of trellised notch according to GOST 15140-78;

- film elasticity in bending according to GOST 6806-73;

- the drying time of the coating according to GOST 19007-73;

- the thickness of a single layer coating on a metal plate is measured with a micrometer.

Properties of varnishes and properties of coatings are given in the table.

At the same time, varnish is prepared and a coating is formed on the metal in accordance with the prototype (examples 9 and 10) and analogs (examples 11 and 12).

From the presented data it is seen that the proposed fluoroplastic varnish based on a copolymer of tetrafluoroethylene with vinylidene fluoride (F-42L) provides the production of coatings on metal with the required properties from it.

The proposed ratios of the copolymer F-42L, acetone, solvents and diluent provide stable production of varnish with a viscosity of 30 to 90 s, while the drying time of the varnish in air does not exceed 6 hours.

The exclusion of xylene and toluene from the organic solvent allows one to reduce the toxicity of the varnish and the danger to personnel working with it, to increase the consumer properties of the varnish in comparison with analogues - the well-known fluoroplastic varnishes F-32L and FPR.

Replacing part of the acetone with other less volatile solvents can reduce the fire hazard when working with varnish.

The use of a mixture of the proposed solvents with high volatility in the manufacture of varnish makes it possible to obtain durable coatings on its basis without heating. Coatings are obtained without smudges, smooth and shiny. This makes it possible to apply multilayer coatings with high performance characteristics on the surface of wood, gypsum and concrete, which allows the proposed varnish to be used in construction and expands the field of its application.

Table
Compositions, properties of varnishes and coatings based on them No. Name Examples of the proposed method Control According to the prototype By analogs one 2 3 four 5 6 7 8 9 10 eleven 12 2 Ftoroplast, brand 42L 42L 42L 42L 42L 42L 42L 42L 42L 42L 32L FPR 3 amount 10 twenty 5 10 twenty 5 fifteen 5 5 twenty 25 40 four Acetone 80 60 10 twenty 10 fifteen 35 fifty 95 80 thirty - 5 Ethyl acetate 10 twenty 35 thirty 25 thirty thirty 25 - - twenty - 6 Amyl acetate - - 35 thirty thirty 25 - - - - - - 7 Cyclohexanone - - fifteen 10 5 10 5 10 - - - - 8 Ethyl cellosolve - - - - 10 fifteen fifteen 10 - - - - 9 Toluene - - - - - - - - - - 25 - 10 Xylene - - - - - - - - - - - 60 Properties of varnish eleven Viscosity, s 40 fifty 35 fifty 70 thirty 60 thirty thirty fifty 90 70 12 1 layer thickness, microns fifteen twenty fifteen twenty 25 10 twenty fifteen 5 10 twenty fifteen 13 Drying time, h 5 5 5 6 6 5 6 5 3 four 7 9 Properties of the multilayer coating (200 μm) fourteen Appearance smooth smooth smooth smooth smooth smooth smooth smooth smooth smooth smooth smooth smooth smooth smooth smooth wrinkled, rough smooth smooth - fifteen Adhesion score one one one one one one one one 0.5 0.5 0.5 one 16 Elasticity, mm one one one one one one one one one one one one

Claims (4)

1. Fluoroplastic varnish based on soluble fluoropolymers, designed to cover various surfaces, which as a fluoropolymer contains a copolymer of tetrafluoroethylene with vinylidene fluoride (F-42L), dissolved in an organic solvent - acetone, characterized in that it additionally contains ethyl acetate in the following ratio of components, wt .%: Tetrafluoroethylene copolymer with vinylidene fluoride 10-20 Acetone 60-80 Ethyl acetate 10-20 2. Fluoroplastic varnish according to claim 1, characterized in that it further comprises a mixture of amyl acetate and cyclohexanone in the following ratio of components, wt.%: Tetrafluoroethylene copolymer with vinylidene fluoride 5-10 Acetone 10-20 Ethyl acetate 30-35 Amyl acetate 30-35 Cyclohexanone 10-15 3. Fluoroplastic varnish according to claim 2, characterized in that it further comprises a diluent - ethyl cellosolve in the following ratio of components, wt.%: Tetrafluoroethylene copolymer with vinylidene fluoride 5-20 Acetone 10-15 Ethyl acetate 25-30 Amyl acetate 25-30 Cyclohexanone 5-10 Ethyl cellosolve 10-15 4. The fluoroplastic varnish according to claim 1, characterized in that it further comprises cyclohexanone and a diluent - ethyl cellosolve in the following ratio of components, wt.%: Tetrafluoroethylene copolymer with vinylidene fluoride 5-15 Acetone 35-50 Ethyl acetate 25-30 Cyclohexanone 5-10 Ethyl cellosolve 10-15