DE1167531B - Process for the preparation of homo- or copolymers of ketones - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Boarding school KI .: C 08 g

German class: 39 c-18

Number: 1 167 531

File number: P 22301 IV d / 39 c

Filing date: February 27, 1959

Opening day: April 9, 1964

It has been found that homo- and copolymers of ketones can be produced if one a ketone of the formula

F ₂ = C - C = O

F ₂ = CC = F ₂

in which F denotes fluorine atoms, polymerized or copolymerized with thiocarbonyl difluoride.

The production of perfluorocyclobutanone, which is not claimed in the context of the invention, is carried out by the following reaction scheme illustrates:

F ₂ C = C-OR F ₂ CC-OR

+ Cycloaddition | | F ₂ C = CF ₂ > F ₂ C - CF ₂

F ₂ CC = O
F ₂ C-CF ₂

Hydrolysis and drainage

The homopolymer produced according to the invention is a white, solid, powdery substance.

In all cases, regardless of the mechanism by which the polymerization takes place, are characterized is effected, the polymers and copolymers of perfluorocyclobutanone by a number repeating oxy (perfluorocyclobutylidene) units of the following structure

F ₂ = <

> = F ₂

The structure of these polymers can thus be understood as a recurring spiro structure. the The main chain of the polymer contains - apart from any units that may be present the comonomers - repeating oxygen and carbon atoms. With the chain carbon atoms of the polymer which are adjacent to the chain oxygen atoms are both remaining Valences through bonding to the α and γ carbon atoms of a perfluorotrimethylene double radical satiated. This particular structure is believed to be at least in part due to the particular properties be responsible for these polymers.

In the case of polymerizations using radicals, in the absence of processes for the preparation of homo- or in the presence of
Copolymers of ketones

Applicant:

E. I. du Pont de Nemours and Company,

Wilmington, Del. (V. St. A.)

Representative:

Dr.-Ing. W. Abitz, patent attorney,
Munich 27, Pienzenauer Str. 28

Named as inventor:

David Charles United Kingdom, Wilmington, Del.

(V. St. A.)

Claimed priority:
V. St. v. America February 27, 1958
(717 805),

dated August 28, 1958 (757 701)

Pathogens work. In general, affect or change the conventional, free radical forming Pathogen the polymerization process very little. Such polymerizations can optionally be carried out in Presence of inert diluents, e.g. B. liquid, organic solvent media take place. About complications however, to avoid these polymerizations it is generally preferred in the absence performed by any diluent.

A variety of pathogens can occur in anionic polymerizations and interpolymerizations or initiators are used. So you can alkali halides, ζ. B. Sodium Chloride, Sodium Fluoride, Potassium bromide, cesium fluoride, cesium chloride, rubidium fluoride, alkali cyanides, ζ. B. Potassium and sodium cyanide; Alkali carboxylates such as sodium acetate, quaternary ammonium salts; ζ. Β. Tetraethylammonium chloride; longer-chain quaternary salts, such as laurylmethyl-phenylsulphonium-methylsulphate; Arylphosphines, e.g. B. triphenylphosphine, or phosphites, such as triethyl phosphite, use. The anionic Polymerizations are preferably in the presence of organic auxiliaries, such as acyclic or cyclic hydrocarbon ethers, e.g. B. dimethyl ether, diethyl ether or tetrahydrofuran, or Ν, Ν-dihydrocarbylmonocarboxamides, e.g. B.

409 558/475

Ν, Ν-dimethylformamide carried out. One works in a conventional manner under anhydrous, oxygen-free conditions and at low temperatures, eg. B. Temperatures in the range of temperatures from liquid nitrogen to solid carbon dioxide (about -80 ° C) up to about room temperature. Preferably, the reaction temperature is below at least about - 50 ⁰ C maintained.

The new polymers and copolymers of perfluorocyclobutanone are suitable for production of molded bodies, e.g. B, of blocks, foils and fibers according to the conventional working methods polymer deformation, e.g. B. by extrusion or spraying from solution, by solution casting or spinning or by direct thermal Conversion from the powdery state. The new polymers and copolymers show an increasingly lower level with an increasing content of oxyperfluorocyclobutylidene units Solubility in solvents. Polymers and copolymers with a major proportion of these Units give excellent resistance to most common organic solvents and are accordingly more difficult to work with, but excellent for the purposes suitable for modern technology, where a high resistance to the dissolving action of organic Substances is desired, such as. B. in packaging materials, parts of compression crimping chambers, bearings. Rods and seals of pumps for chemical processing and devices for the Handling of fuels. In general, such products are based on direct thermal Ways made by grinding, pressing, calendering, injection molding and the like.

The anionic homopolymers are easy to handle, stable, solid substances. You are therefore a convenient source of the chemically quite reactive and therefore difficult to handle perfluorocyclobutanone. If z. B. the perfluorocyclobutanone with another chemical substance to new If derivatives of the ketone are to be implemented, the solid homopolymer can be heated to elevated temperatures heat and distill the monomer produced thereby directly into the reaction vessel used.

In the following examples, all parts are parts by weight unless otherwise specified.

example 1

0.01 part of anhydrous sodium acetate is added to a solution of about 8 parts of perfluorocyclobutanone (bp. 3 to 4 ° C; freezing point about -58 ° C) in about 10 parts (dried over sodium) anhydrous diethyl ether at 0 ° C the mixture stand for 10 minutes at 0 ^° C. and then cools from the outside by means of a bath of solid carbon dioxide and acetone. Polymerization can be perceived within minutes after the reaction vessel has cooled down. After 16 hours under these conditions there is a solid, opaque, white gel in the reaction vessel. About 2.2 parts of acetyl chloride are added and the gel is mechanically broken up while the reaction vessel is kept at about -80.degree. The mixture is allowed to warm to room temperature for 10 minutes and after 1 hour at room temperature the reaction mixture is filtered and the solid substance is washed with petroleum ether, diethyl ether, alcohol and water and finally dried.

In this way, about 2.5 parts of poly- [oxy- (perfluorocyclobutylidene)] are obtained in the form of a white powder, which can be used in solvents as varied as acetone, methyl and ethyl alcohol, benzene, chloroform, methylene chloride, petroleum ether, acetonitrile, acetic acid, Acetic anhydride, butyrolactone, sulfuric acid, trifluoroacetic acid, tetramethylurea and p-chlorophenol is insoluble at room temperature and on boiling. The polymer slowly releases monomer at room temperature and decomposes ^{quickly and cleanly at 200 to 250 °} C. to form perfluorocyclobutanone. The X-ray and infrared spectra agree with the poly [oxy (perfluorocyclobutylidene)] structure.

About 0.5 part of anhydrous dimethylformamide and about 0.5 part of triethylphosphoric are added to a solution of about 8 parts of hexafluorocyclobutanone in about 16 parts (dried over sodium) of anhydrous diethyl ether at ^{0 ° C. and the mixture is left at 0} ° C. for about 30 minutes stand, with no visible change. The reaction mixture is then cooled externally by means of a bath of solid carbon dioxide and acetone. Polymerization is noticeable within minutes of using the cooling bath. The reaction mixture is kept at the temperature of a bath of solid carbon dioxide and acetone overnight. In this way, after removal of residual, unpolymerized monomer, filtration and evaporation of the ether medium, about 2.0 parts of a solid, white, high molecular weight homopolymer of perfluorocyclobutanone, which is similar to that described above, are obtained. Essentially identical results are obtained if 1.0 part of triphenylphosphine is used instead of the triethyl phosphite.

B e i s ρ i e 1 2

A reaction vessel made of glass, the capacity of which corresponds to 500 parts of water and that with Inlet and outlet pipes and a mechanical stirrer is fitted with about 70 parts anhydrous diethyl ether and about 0.15 part of dimethylformamide are charged. The reaction vessel will purged with nitrogen and then immersed in a bath of solid carbon dioxide and acetone. In the solution under water- and oxygen-free conditions and with vigorous stirring slowly about 10 parts initiated gaseous perfluorocyclobutanone. Stirring and cooling are continued for 8 hours, whereupon the reaction mixture is allowed to warm to room temperature. The diethyl ether will evaporated by passing a stream of nitrogen over the surface of the reaction mixture.

This gives 5.9 parts of a clear gel of poly [oxy (perfluorocyclobutylidene)] in diethyl ether, which smells strongly of monomeric perfluorocyclobutanone and slowly liquefies if it is left to stand for a few hours at room temperature. Heating a sample of this product and collects the vapors obtained in one to about - 80 ⁰ C cooled template. The condensate is broken down by distillation into a fraction boiling above and below room temperature. The lower-boiling fraction represents how a comparison of the nuclear magnetic resonance spectrum with that

of the known monomer shows recovered perfluorocyclobutanone, the higher-boiling fraction in contrast, a mixture of poly [oxy (perfluorocyclobutylidene)] of relatively low molecular weight and diethyl ether.

Example 3

In a reaction vessel made of glass, which is equipped with a magnetic stirrer, has been flushed well with a stream of helium gas and is ^{cooled from the outside in a bath of solid carbon dioxide and acetone to about -8O 0} C, about 12, 5 parts of anhydrous (dried over sodium) diethyl ether, about 4.5 parts of liquid Thiocarbonyldifluorid (measured at - 8O ⁰ C), about 4.8 parts perfluorocyclobutanone (about 3 to 4 ° C above the melting point), about 3.5 parts of other anhydrous diethyl ether and finally about 7 parts of anhydrous diethyl ether containing about 0.1 part of dimethylformamide were added. In the reaction mixture a solid polymer precipitates in the next two hours of gradually to give the reaction vessel at about - 8O ⁰ C holds. The reaction mixture is then poured into hot water to abort to the diethyl ether and the resulting solid substance well water and then with acetone and finally dried in a vacuum oven at 6O ⁰ C and.

In this way, 2.7 parts of a light yellow-brown thiodifluoromethylene-oxy-ihexafluorocyclobutylidene copolymer are obtained in the form of a pulverulent solid with an intrinsic viscosity of 0.90 (determined in chloroform at 25 ° C. and a concentration of 0.1%). The analysis shows that the copolymer consists of 83 parts of thiodifluoromethylene and 17 parts of oxyperfluorocyclobutylidene. If the copolymer is pressed for 2 minutes at 150 ° C. and 844 kg / cm ² , a soft, self-supporting, clear, limp film is obtained.

Analysis for 83 / 17CF ₂ SZC ₄ F ₆ O:

Calculated ... C 18.4%, H 0.0%, F 51.6%;
found ... C 18.5%, H 0.6%, F 50.5%.

Claims (1)

Claim: Process for the preparation of homo- or copolymers of ketones, thereby characterized in that one has a ketone of the general formula F ₂ C-C = O F ₂ in which F denotes fluorine atoms, polymerized or copolymerized with thiocarbonyl difluoride.