DE2235885C3 - Fluorocarbon waxes, aqueous fluorocarbon wax dispersions and processes for their preparation - Google Patents

Description

According to the state of the art, there are two basic production routes for fluorocarbon waxes known:

Manufactured by pyrolysis of Huorpolymcren or telomerization of fluorine-containing monomers in organic solvents.

The pyrolytic decomposition of Fiuorpolymcren at temperatures above 400 C is for example described in US-PS 2,4% 978. GB-PS 1,047,76S and DT-PS 1,049,099. The process has several each Disadvantage. That used as a starting product / ie

Fluoropolymers is an extremely expensive product because of its production, so that the production route is only feasible by pyrolysis. if such polymers are incurred as waste, the otherwise cannot be used, l-.me

Manufacture of fluoropolymers solely with the aim of achieving this subsequent pyrolytic degradation is out of the question for economic reasons. In the case of the pyrolysis itself, a considerable loss in yield must also be accepted as a result.

that the reaction cannot be izelenkl only to waxy products, but always in addition liquid and gaseous by-products arise. Hydrogen fluoride can also be split off With all of its disadvantages with regard to corrosion of the reaction apparatus, it should never be completely avoided. Ultimately, the product of such pyrolysis always falls in the form of compact blocks. Tubers or Cake on. and must then be brought to the desired grain size by grinding.

To circumvent these difficulties, attempts have already been made to use fluorocarbon waxes by telomerization of chlorine-containing monomers at elevated pressure and temperature in the presence from radical initiators. In these cases, the solvent takes over at the same time Role of telotia. Describe such procedures U.S. Patent Nos. 1,2,411,158. 2,433,844. 2,569,628 and 2,562,547. Following Example 2 of British Patent 1,069,089 a polytetrafluoroethylene wax is obtained in carbon tetrachloride having a molecular weight of 20,000. US Pat. No. 3,105,824 also discloses a method known in which the telomerization of tetrafluoroethylene in which t: lied little active 1.1.2 tri

jhlortrifluoriilhan as a solvent with addition low levels of a highly active telogen. how for example methanol or methylcyelohexane, carried out at temperatures in the range from 75 to 200.degree will. This procedure has the advantage over the previously mentioned that the fluorocarbon wax transferred from the originally purely organic solvent phase into the aqueous phase can be. For this purpose, the suspensions of the fluorocarbon wax obtained are added to 1,1,2-trichlorotrifluoroethane initially mixed with water-soluble emulsifiers. Then half the solvent distilled off and then the remaining solvent with the gradual addition of water and removed with stirring. This procedure is inconvenient because of the large number of its process steps as well as because of the necessary recovery and Drying of the solvent. It is in principle possible to use them as aqueous dispersions of fluorocarbon waxes to be obtained, but only in the lower molecular weight range up to approximately in the range from 2000.

The fluorocarbon waxes with a molecular weight range that are particularly interesting for industrial use from 30,000 to 200,000, however, the first falls in the course of the aforementioned procedure produced suspension during production or within a short time.

This is evidently due to the rapid growth of the primary particles initially formed during the telomerization and especially during the removal of the solvent due to the Granulating effect is known for such solvents. Obtaining stable dispersions of fluorocarbon waxes also does not succeed by adding water-soluble emulsifiers in the solvent phase and subsequent replacement of the organic solvent with water.

The present invention relates to a process for the production of fluorocarbon waxes by telomerization of tetrafluoroethylene, optionally in a mixture of 0.1 to 40 mol percent - based on telrafluoroethylene - · on comonomers of the formula

CH ₂ = CH ₂
CF ₂ = CFX (X = H, CF ₃ , Cl, Br, J)
or CF ₂ = CX ₂ (X = H, Cl, Br, J)

or with mixtures of these comonomers. in the presence of 0.1 to 15 percent by weight, based on used monomers, a telogenic connection of the sum forms!

CH _n X ₄ - ,, (n = 0 to 3, X = Cl, Br) or
C ₁₁ F _{2n + 1} J (n = 1 to 3) or the formulas
CH ₃ J ₁ CF ₂ J-CF ₂ J or
CFJ ₂ -CF ₃

45

55 homopolymerization are used at temperatures from 0 to 40 'C and at pressures of 0 to 25 atm using a specific stirring energy in the range of 2.4 x 10 ^"5 to 3.5 × 10 ^-5 kp ■ m / sec / cm ^{3 is} telomerized.

The process according to the invention is carried out in a purely aqueous phase, in addition to the telogenic Compound does not contain any organic solvents. The aqueous Telomerisaticnsflotte is before Start the reaction by adding an appropriate amount of dilute, aqueous ammonia solution Adjusted to be slightly alkaline (pH 7.1 to 9). Telomerization could in principle also be carried out at pH values <7, i.e. in the acidic range. However, this leads to an undesirable Reduction in the stability of the resulting dispersion and thus also to one undesirable increase in the grain diameter of the coagulated powder.

The telomerization takes place in the presence of water-soluble initiators and in the presence of water-soluble emulsifiers, which are known and customary from tetrafluoroethylene dispersion homopolymerization. The initiators with a disintegration half-life that is suitable for the temperature range mentioned are above all the known redox starter systems, such as ammonium persulfate / sodium bisulfite, for example. Ammonium persulfai hydrazine. Ammonium persulfate iron (II) salts and iron (III) salts / sodium bisulrite. Particularly suitable emulsifiers are ammonium or alkali salts of perfluorocarboxylic acids or * · < -hydrofluorocarboxylic acids.

The telomerization is carried out at a pressure in the range from normal pressure to 25 atm. preferably in the range from 6 to 18 alü. The temperatures used are between 0 and 40 C, preferably between 20 and 35 C. In order to achieve a sufficient and constant rate of polymerization, the specific stirring energy compared to homopolymerization of tetrafluoroethylene in dispersion under comparable pressure, temperature and apparatus conditions must on average be around 50% can be increased. It lies between 2.4 · 10 ^-5 to 3.5 x 10 ^"5 kgf · m / sec / cm ³ (at the Homopolymerisalion of tetrafluoroethylene between about 1.2 × 10 ^-5 to 2 × 10 ^-5 kg · m / sec / cm ³ ).

It is of particular advantage that the inventive Process can be carried out in the same equipment as the large-scale Tetrafluoroethylene dispersion polymerization. As a starting monomer in the invention Process preferably used tetrafluoroethylene alone. Tetrafiuoräthylcn can, however, also together with comonomers of the formula

CH ₂ = CH ₂

CF ₂ = CFX (X = H. CF ,, Cl, Br, J) or CF, = CX, (X = H. Cl. Br. J)

or a mixture of the telogenic compounds mentioned in the presence of free radical initiators, which is characterized. that in aqueous, weakly alkaline phase in the presence of free radical initiators and emulators, telomerized for the Tctrafluoräthylen-Dispcrsions- or with mixtures of such monomers will. These comonomers or monomer mixtures are used in amounts of 0.1 to 40 mol percent, preferably 1 to 15 mole percent based on tetralluoroethylene. used. Next to the Ethylei are to be mentioned in particular as comonomers Tn

fluorochlorethylene, trifluoroethylene, trifluorobromethylene, Trifluoroiodethylene. Hexafluoropropylene and!, L-difluoro-l ^ -dichlorethylene. As telogens are used compounds of the summation formula

5 CH _n X ₄ -, (π = 0 to 3, X = Cl, Br) or

C _n F _{2n + 1} J («= 1 to 3) or the form no

CH ₃ J, CF ₂ J-CF ₂ J or

CFJ ₂ - CF ₃

Of these compounds, particular mention should be made of dibromochloromethane, dichloromonobromomethane, Methylene chloride, dibromodichloromethane, carbon tetrachloride, bromoform, methyl iodide, Pentafluoroethyl iodide, perfluoroisopropyl iodide and 1,1- and 1,2-diiodotetrafluoroethane. Particularly preferred is chloroform. The compounds mentioned can be used individually or as a mixture will. The telomerization is carried out in the presence of 0.1 to 15 percent by weight, preferably 0.4 to 10 percent by weight, of telogen or telogen mixture. based on the amount of starting monomer or of the starting monomer mixture. In general, the telogen or the telogen mixture is set before the start added to the reaction of the aqueous liquor. However, it can also be telogen insofar as it is gaseous Compounds acts, mixed in a mixed gas battery with the monomer or monomers and together be conveyed with these at constant pressure in the telomerization autoclave. In another Embodiment can supply the TeIogen separately from the monomers with the help of a Microdosing takes place, whereby gaseous or volatile telogens by an at the Dosing system attached cooling device can be converted into the liquid state.

In general, a purely aqueous liquor is presented with the indicated auxiliaries. But when within the specified range of the particle size of the initially resulting fluorocarbon wax dispersion a shift in the direction of the upper limit is desired, one according to the invention Process obtained fluorocarbon wax dispersion are presented as seeds. The aqueous liquor is adjusted so that the Solids content of these seeds 0.3 to 3.0, preferably 0.5 to 2.0 percent by weight, based on the total weight of the starting fleet. A seed dispersion is preferably used which consists of the same Starting monomers using the same telogens as those made using the then come to reaction in the main telomerization. However, it is also possible to use one with regard to the Seed with a different composition of starting monomers and / or one produced with other telogens Seed dispersion, obtained by the process according to the invention, to be initially introduced without the resulting Dispersions or fluorocarbon wax powder leave the scope of the invention in their properties.

It was extremely surprising that the space-time yields of the process according to the invention are of the order of 150 to 300 g / l / h, d. H. in the same order of magnitude as that Space-time yields of the large-scale polymerization of Tetrafluoräthyien. In itself would have expected must be that the presence is celt-carrying Telogen compounds, as known in the art, delay the response and a reduction in space utilization leads.

The initially resulting fluorocarbon wax dispersions are surprisingly of exceptional stability. During the telomerization and after the end of the same, no coagulum formation is observed despite the more stringent stirring conditions. Therefore, the addition of a coating agent such as is often used in tetrafluoroethylene polymerization in the form of waxy hydrocarbons and the like! is proven to be superfluous. The primarily resulting fluorocarbon wax dispersions are so stable 'dnl'. Can be telomerized without difficulty up to a solids content of 40 percent by weight, based on the total weight of the dispersion.Of course, very low solids contents can also be achieved, but you will usually telomerize at least 5 percent by weight, preferably up to 20 percent by weight, solids content.

Solids contents higher than 40 percent by weight can be achieved by post-treatment using the customary methods the distillative concentration or the electrode canting achievable.

The invention thus also relates to aqueous fluorocarbon wax dispersions which are characterized in that they have been prepared by the process according to the invention and spherically shaped telomerizate particles with an average particle diameter of 0.01 to 0.5 μm and with a narrow size distribution, expressed by contain the value \ d \ / 2 / d _av < 0.35.

This value Ad \ / 2 / d _av is derived from the particle diameter distribution curve. This curve is obtained by counting the particle diameters which can be measured in the electron microscope image of the dispersion. The abscissa value associated with the curve maximum corresponds to the variable d _ar . A straight line is drawn through the middle of the corresponding ordinate value parallel to the abscissa axis and the distance between the intersection points of this straight line with the two branches of the distribution curve is denoted by IJ 1/2.

The mean particle diameter of the spherically shaped dispersion particles is preferably 0.03 to 0.2 _μ ; the value \ d \ / 2 / d _av for the size distribution is preferably between> 0.20 and <0.35.

The fluorocarbon wax dispersions initially obtained are then optionally coagulated and dried to powder. The coagulation can in principle take place by customary methods, with because of the high stability of these dispersions with regard to the agents to be used - chemical precipitants or mechanical energy - more severe conditions must be applied. Coagulation can be done by adding acids to the dispersion with simultaneous stirring, the dispersion being adjusted to a pH of 6 to 2. In concentrated hydrochloric acid is primarily used, but organic acids, such as acetic acid can be used. Precipitation electrolytes can also be used in place of acids in the form of concentrated salt solutions, such as solutions of sodium chloride. Ammonium chloride, ammonium carbonate and potassium carbonate.

■ egg
G-

In
in
: n,
\ n
/ te
let
mnd

The use of acid for coagulation, however, has the advantage that during the subsequent neutralization of the precipitated dispersion with carbonates, in particular ammonium carbonate, better and faster separation of the precipitated fine powdery wax from the mother liquor is achieved under the action of the released CO ₂ . The wax floats on the surface after a short time and can be easily separated and washed by repeatedly adding water.

The dispersion can also be coagulated by mechanical stirring, with increased stirring energies from 0.35 to 0.40 PS / 1 are to be used.

If the dispersion is coagulated by means other than acids, it is optional to neutralize beforehand.

The drying of the precipitated coagulum to fluorocarbon wax powder is best carried out in convection or vacuum drying ovens at temperatures of 80 to 200 ⁰ C, preferably 100 to 170 ⁰ C.

In the known coagulation of polytetrafluoroethylene dispersions pulverulent dispersion polymers are obtained which consist of agglomerates of primary particles, the mean particle diameter such agglomerates between 200 and 1000 μ is. It was therefore extremely surprising and not foreseeable that the coagulation obtained by the process described Fluorocarbon wax dispersions to form extremely fine powders with an average particle size of the primary grain from 0.5 to 6 μ, preferably from 1 to 3 μ, and leads to novel product properties.

The invention therefore also relates to fluorocarbon wax powders with an average molecular weight in the range from 10,000 to 200,000, preferably 30,000 to 150,000 Grain distribution of the primary grain, expressed by the size \ d \ / 2 / d _av < 0.9 (measured according to the method described above), with these primary grain particles being more than 70% associated with a loose, grape-shaped compound with a diameter of 8 to 20 μ, and further, a specific surface area of 10 to 26m ² / g (measured by the BET method), a total pore volume of 80 to 120 ^cm3 / 100 g dry matter, a transition temperature crystalline / amorphous 270-325 ° C and VCN an apparent melt viscosity 0.7 · 10 ² to 1 · 10 ⁸ poise at 380 ⁰ C and 20 kp / cm ² .

The size distribution of the primary grain \ d \ / 2 / d _av is preferably> 0.7 and <0.9. The preferred values for the transition temperature crystalline / amorphous are 290-325 ⁰ C, the apparent melt viscosity of 1 × 10 ³ to 1.5 ■ 10 ⁷ poise (at 38O ⁰ C und200kp / cm ^2).

The association of the primary grain of the fluorocarbon wax powder obtained to form larger, grape-shaped structures of 8 to 20 μ, preferably 10 to 15 μ. average grain diameter and to an extent of> 70%, preferably 75 to 100% of the total number of primary grain particles can be determined when taking pictures under the electron microscope. Because of this structure, the fluorocarbon wax powders according to the invention have a fairly low tendency to form dust, which is otherwise unpleasant when processing similar finely divided materials. Therefore, these powders can also be dried without difficulty in circulating air drying cabinets. The measurements of the total pore volume with the Hg porosimeter (model 65, Erben, Milan) are based on the following principle: A certain pressure is required for the penetration of mercury into a porous material, regardless of the mean pore diameter. When the pressure is increased gradually, all pore sizes are filled with mercury one after the other. In addition to a so-called pore spectrum, the total pore volume is determined from these measurements through integration of the amount of mercury absorbed. For the fluorocarbon wax powder according to the invention, the measurements showed a total pore volume in the range from 80 to 120, preferably 90 to 100 g, dry substance in the pressure range from 1 to 1000 atm, recording the pore spectrum from 12.5 to 0.015 μ. ^{In comparison, values of 50 to 60 cm 3} / -100 g dry substance were obtained for fluorocarbon waxes obtained by pyrolytic degradation under the same measurement conditions. Coagulates of dispersion polymers of tetrafluoroethylene also provide values for the total pore volume which are in the range of the values for pyrolytic degradation waxes.

The specific surface area of the fluorocarbon wax powder according to the invention is determined by the BET method (S. Brunauer, RH. Emmet, GJ Teller, J. Am. Chem. Soc. 60. 1938. p. 309). It gave unexpectedly high values of 10 to 26 m ² / g. preferably from 12 to 20m ² / g. For comparison, the waxes obtained by means of pyrolytic degradation had an average grain diameter of about 6 μm, even after prior fine grinding. Values for the specific surface area of 3 to 6m ² / g. The dispersion polymers suitable for paste extrusion because of their pore-rich syrup (each polytetrafluoroethylene only reach 7.6 to 9 ii ·,: μ

It also concludes that dit Fluorocarbon wax powder according to the invention unexpectedly using high stirring forces (for example, using a high-speed rest rers of the Ultra-Turrax type) at about 10000U / mii too stable in organic solvents such as perchlorethylene, toluene and benzene! Dispersions are redispersible. You could stable dispersions are obtained which have a mean particle diameter of about 0.1 μ bi contain 20 percent by weight solids. Pyrolyti see degradation waxes show this property Redispersibility does not arise.

The fluorocarbon wax dispersers according to the invention Sions can be used for various technical purposes. They can be used at the Aul Laminating foils made of polytetrafluoroethylene, tetrafluoroethylene copolymers and poly tetrafluoroethylene compounds «on metal surfaces as an additive to polytetrafluoroethylene coating Materials in the form of dispersions improve the freedom from pores and adhesion to the sub-surface of such coatings. They can also be used to impregnate glass fibers and asbesi products, where they are better in the material eir

penetrate as Polytetrafiuoräthylen-Dispersionen and also the lower sintering temperature and the lower melt viscosity are advantageous. Stable fluorocarbon wax dispersions can also be used with other aqueous plastic dispersions, such as. B. polyvinyl chloride, polytetrafluoroethylene and polystyrene dispersions are mixed in a dispersed state. If such dispersions are precipitated. in this way, uniform mixing with the fluorocarbon wax particles in the coagulate is maintained and gives improved processability. z. B. as a release agent. Finally, the invention Fluorocarbon wax dispersions with exchange of the water in an organic solvent phase are transferred and then serve as dry lubricating sprays or in combination with others organic synthetic resin solutions as bonded coatings.

The fluorocarbon wax powders according to the invention are valuable additives for lubricants and polishes.

They can also be used as sprays because of their finely divided form in dispersion also as lubricants, but also for the production of water- and oil-repellent or against corrosion protective coatings can be applied. In intimate mixtures with other plastics, such as Polypropylene, polyamides. Phenolic or epoxy resins, they can be used to make self-lubricating Storage parts are used in devices subject to friction. Fluoicarbon waxes in very finely divided form Powder form have proven particularly useful as mold release agents, release agents and lubricants in plastics processing and proven in deep drawing of metal sheets. In all of these applications, the high Fine division of the fluorocarbon wax powders according to the invention is of considerable importance. this applies especially for the addition to lubricants, as well as in the production of coatings and Coatings where the fine division results in a significantly improved homogeneity.

The following examples are intended to explain the invention without limiting their scope.

^v 10

b) work-up

The resulting fluorocarbon wax dispersion was reduced to a solids content of 10 to 20 percent by weight diluted by adding water, mixed with about 3 percent by weight of concentrated hydrochloric acid and stirred in the polymerization kettle at 130 to 140U min. The subsequent neutralization of the Hydrochloric acid with ammonium carbonate caused the coagulated product to float. The one in the lower Aqueous phase that had settled out of the kettle was drained through a bottom valve. By adding three times the product was washed by deionized water with stirring (20 rpm) and that rapidly Settling wash water is drained after each washing process. The moist powder remaining in the kettle was then dried on metal sheets in a circulating air drying cabinet at 150 to 200.degree.

Tables 1 and 11 summarize the test batches with the addition of the starting monomer or monomers and telogen and the reaction conditions. The reproduced in Table I. Try the specific stirring energy 3.0 x 10 ^"5 kg · m / lake / cm ³ was in the reproduced in Table 11 experiments 3.5 ■ 10 ~ ⁵ kgf · msec cnr \ The values given in Table 111 were obtained, unless already described above, as follows: The mean particle size of the primary grain of the wax powder was determined by counting and measuring the particles visible in the electron microscope powder image.

The procedure for determining the melt viscosity was as follows: The amount of extruded material was used Melt and the unit of time determined at a given temperature under a given pressure exits from a nozzle with given dimensions (diameter and length). The is calculated from this apparent melt viscosity

Examples

General working regulations
a) Telomerization

If not, the Tclomerisationsansatzc were otherwise noted, carried out in enamelled 40-1 stirred autoclaves equipped with propeller stirrers. 17 g of perfluorooctanoic acid were added to the liquor of deionized water placed in the stirred autoclave dissolved and the pH adjusted to 8 to 9 by adding aqueous ammonia solution. The respective Telogenc were either submitted with the aqueous liquor or together with the Monomers premixed in a mixed gas battery or metered in separately during the telomerization. After repeated flushing with nitrogen, the monomer or the monomer mixture was in the Kettle pressed and the batch after reaching the reaction temperature and switching on the stirrer by adding 2.8 g of ammonium persulfate and 1.76 u of sodium bisulfite. partly dissolved in water, started.

wherein

= Extrusion pressure [dyn cmr].

= Nozzle radius [cm].

= Nozzle lengthc [cm],

- amount of extrudate escaped [env ¹ see]

The melt extrusion was carried out with a high pressure capillary viscosity meter from Gott fert under the following measurement conditions (unless otherwise stated): 380 C. 200 kgf cm ² extrusion pressure. Nozzle dimensions 1 mm in diameter. 40 mn length.

The extrudate is given in cm ³ , with the BET measurements being carried out with the absorption of argon at -195 ° C. The dispersion stability of the fluorocarbon wax dispersions obtained was measured with a rotary viscometer from Haake on dispersions with a 20% plastic content ; the failures are indicated; <n minutes. · ■

11 T

Table I Telomerization with mixing of the telogen with the monomer or monomers in the mixed gas battery

Λ starting monomers (s) Telogen pressure 1 cmp. Submitted
Part of the hall,
related to
Exit frenzy l-estsloff-
gchali the
received
Dispersion Mean
Particle
size of the
Primary grain Conversion Ver
search
No. (Wax- lung
temperature
crystalline
amorphous (Weight (Weight powder) (Wax (Weight percent) Kit weight percent) (atiil (C) percent) percent) (μ) powder) 99.5CF ₂ = CF ₂ 0.5CF ₃ -CF ₂ J. 19th 32 0.8 ² ) 22nd 6th C ¹ C) I. 98,8CF ₂ = CF ₂ 1.2 CF ₃ -CF ₂ J 14th 25th 23 L5 324 1 97.7CF ₂ = CF, 2.3 CF ₃ -CF ₂ J 17th 34 27 2.0 320 3 96,3CF ₂ = CF ₂ 3.7CF ₃ -CF ₂ J. 19th 32 30th 1.8 319 4th 94,6CF ₂ = CF ₂ 5.4CF ₃ -CF ₂ J ¹ ) 19th 32 35 1.7 318 5 90.2CF ₂ = CF, 9.8CF ₃ -CFJCF ₃ 19th 32 28 1.5 317 6th 88.0CF ₂ = CF ₂ 12.0 CF ₃ -CFJ-CF ₃ 19th 32 21 2.5 310 7th 85, OCF ₂ = CF, 15.0 CF ₃ -CFJ-CF ₃ 19th 32 28 2.0 311 87.3CF, = CF, / 1.2 CF _{3 CF 2} J. 17th 32 20th 1.2 310 9 11.5 CF ₂ = CFCl 299 84.5 CF ₁ = CF ₂ / 7.5 CF ₃ -CF ₂ J 17th 36 25th LO •O 8.0CF ₂ = CFCl 292 88.0 CF ₁ = CF ₂ / 7.5 CF ₃ -CF ₂ J 17th 32 25th 1.1 11th 4.5 CF ₂ = CH ₂ 271 80.5CF ₂ = CF, / 7.5 CF ₃ -CF ₂ J 17th 32 20th 1.5 12th 12.0 CF ₃ -CF "= CF ₂ 318 86.7 CF ₁ = CF, / 8.8 CF ₃ -CF ₂ J. 17th 32 20th 1.5 13th 4.5 CF ₃ -CF = CF, 315 92.0CF, = CF, / 2.0 CF _{3 CF 2} J. 17th 32 17th 2.0 14th 6.0CF ₂ = CFBr 319 9L0CF, = CF, / 4.0CF ₃ -CF ₂ J 14th 15th - 15th 1.7 15th 5.0CF ₂ = CFJ 317 93.OCF ^ = CFV 4.0CF ₂ J-CF,.! 20th 32 2Xr ¹ ) 12th 2.6 16 3.0 CH, = CH, 316

¹ I metered in during the telomerization. ^: l Same composition of the seeds (as experiment 1). Ί The same composition of the seeds (as in experiment 7 |. ⁴ I composition of the seeds as in experiment 4.

Table II Telomerization with submission of the telogen in the aqueous starting liquor

/ far 1 clogen pressure Ί emp Submitted K-.isioff- MmI. Around Monomcrcs Seed percentage. gchiill the Particle change (Weight related to received size of the temperature attempt (Weight percent) (aiii) (Ci Starting Dispersion Primiir crystalline No. percent) ') CF ₃ -CF ₂ J (0.8) 17th 32 fleet grain amorphous CF ₃ -CF ₂ J (2.4) 14th 25th (Weight (Weight (Wax (Wax CF ₃ -CF ₂ J (4.4) 14th 32 percent ι prozcni) powder) powder) C ₂ F ₄ Br, (3.9) 17th 32 24 (μ | CC) 1 CCl ₄ (IO) 14th 32 L5 ² ) 28 2.5 321 2 CF ₂ = CFCl (5) CHBr ₃ (LO) 17th 30th 34 4.5 317 3 - CHClBr ₂ (LO) 17th 28 17th 1.2 307 4th - CF _3. ! (0.5) 17th 32 20th 3.0 327 5 CHBrCl ₂ (LO) 17th 32 - 27 1.5 318 6th CHCI ₃ (LO) 17th 32 19th 1.4 320 7th 20th 1.7 324 8th 20th 2.5 321 9 20th 1.9 323 10 1.7 321

') Remainder against 1 (X) from the sum of percent by weight of second monomers + percent by weight of Tclogcn or percent by weight of telogen alone

= Percent by weight of tetrafluoroethylene used. ^; ) Composition of the seeds as in experiment 5.

attempt

/ far
Monoinercs

(Weight percent) ¹ )

CF ₂ = CH ₂ (5)

CF ₅ = CCl ₁ (5)

Telogen

(Weight percent)

CHCl ₃ (LO) CHCl., (3.7) CHCl ₃ (4.5) CHCl ₃ (8.0) CH ₂ Cl ₂ (3.7) CHCl ₃ (LO) CHCl ₃ (0.2)

continuation

I cmp

(aiii) 14 14 14

14 14 14 14

(O

28 28 28 25 20 32 32

Present part of the hall.

related to

Initial

fleet

(Weight percent)

1.5 ³ }

Boston-gchall's
received
Dispersion

(Weight percent I.

18th
20th
18th
20th
17th
20th
20th

Mean particle size of the primary grain (Wax powder)

(μ)

L8

1.8 1.3

') The remainder against 100 from the sum of percent by weight of the second monomer

= Percent by weight of tetrafluoroethylene used. ¹ I Composition of the seeds as in experiment 14.

Table 111

2.5 2.5

Weight percent Tclogcn or weight pro / enl

Around-

transformative

tempcr.itm

knslallm-

amorphous

(Wadis-

powder

((I 318

318 315 320 318

Teloucn alii

Properties of the fluorocarbon wax powders and dispersions

I. Rotovisko stability
the dispersion (Sec.) (all together
pore
from Iu men 1 xtrudat False sharks
Melt viscosity Specific Primary grain "" ■ '"" I. (Mini 50 cm ³ KK) μ) (civ. min.) (Poise I surface
according to BIT distribution
of the powder
! (/ 1 ^ <'.,. attempt I. 4th 20th 112 1.4 7200 (m ^: gl _r . I tab. I. 5 40 114 1.4 5140 15th 0.8 ..... I. 5 30th 117 2.5 2995 17th ¹ 1
2 1 4th 112 3.0 2406 T) 3 I. 6th 20th 110 4.0 1800 T) 4th I. 10 20th 116 45.0 160 16 0.75 5 I. 8th 30th 115 60.0 120 18th 6th I. 20th 10 113 75.0 4 (1 14th 7th I. 15th 25th 117 3.0 2406 Iv 0.S5 8th I. 16 8 I. 115 44 165 20th 9 ] 9 10 108 35 206 23 10 J 9 106 55 131 25th π j 7th 20th 104 50 145 18th 12th ] 4th 10 103 3.0 2406 23 13th π 3 30th 101 2.5 2995 17th 14th Il 5 45 105 3.0 2406 14th 15th H 6th 30th 107 1.0 7200 Ti 6th π 7th 10 107 10.0 720 18th 0.78 1 π 4th 15th 104 100.0 72 22nd 2 Il -> 10 102 0.3 2400 23 3 II 8th 25th 110 10.0 720 18th 4th π 3 40 104 8.04 ■ 10 '*) 3.05 ■ 10 ^s 16 0.89 5 II 1 50 105 8.76 -ΙΟ " ³ *) 28 · ΙΟ ⁵ T> 5 π \ 35 101 1.4 5140 21 7th Il -) 45 103 1.9 ■ ΙΟ " ³ *) 134 - ΙΟ ' 19th O π 2 40 104 2.32 *) 1.1 - 10 ⁴ 17th O
9 Π 8th 40 110 0.51 *) 50 10 ' 15th 10 π 4th 10 107 2.88 *) 9000 22nd ι ι π 25th 4th 105 5.8 *) 4400 24 1 I.
1 1 11th 20th 50 118 21.3 *) 1200 20th 0.78 \ L.
\ τ. II
11th 6th 50 106 2.75 *) 9300 16 I. "
14th T 30th 101 0.51 *) 50 10 ³ 19th I ^ T
ι <; 7th 108 2.17 ■ ΙΟ " ³ *) 113.4 ■ 10 ⁵ 21 I _ '
1 ί. 16 0.88 16
17th

* «-1K0 C. 7..1 kp cnr: nozzle 2.0H mm: 1 iinpe- S mm

Claims (7)

Patent claims: 1. Process for the production of fluorocarbon waxes by telomerization of tetrafluoroethylene, optionally in a mixture with 0.1 to 40 mol percent - based on tetrafluoroethylene - of comonomers of the formula CH ₂ = CH ₂ ίο CF ₂ = CFXCX = H, CF ₃ . Cl, Br. J)
or CF ₂ = CX ₂ (X = H, Cl, Br. J) or with mixtures of these comonomers. in the presence of 0.1 to 15 percent by weight, based on the monomers used, a telogenic compound of the empirical formula CH _n X ₄ - ,, (n = 0 to 3, X = Cl, Br) or
C _n F _{2n + 1} J (11 = 1 to 3) or the formulas
CH ₃ J, CF ₂ J-CF ₂ J or
CFJ ₂ - CF ₃ or a mixture of said telogenic compounds in the presence of free radical initiators, characterized in that in the aqueous, weakly alkaline phase in the presence of free radical initiators and emulsifiers which are common for tetrafluoroethylene dispersion homopolymerization, at temperatures of 0 up to 40 "C and at pressures from 0 to 25 aluminum using a specific stirring energy in the range of 2.4 · 10" ⁵ to 3.5 ^{· 10 "5} kp · m / sec / cm ^{3 is} telomerized. 2. The method according to claim 1, characterized in that the telogenic compound mil the aqueous liquor is presented. 3. The method according to claim 1, characterized in that the telogenic connection with the Tetrafluoroethylene, optionally premixed with the monomer mixture, in a mixed gas battery and this mixture is fed to the aqueous liquor. 4. The method according to claim 1 to 3, characterized in that one with the aqueous liquor Fluorocarbon wax seed dispersion, obtained by the method according to claim 1, is presented, the proportion of seeds in the aqueous liquor being 0.3 to 3 percent by weight, based on the total weight of the starting fleet. 5. The method according to claim 4, characterized in that the seed dispersion presented from consists of the same monomers and was obtained using the same telogens as in the main telomcrisation. 6. Aqueous fluorocarbon wax dispersions, characterized in that they have been prepared by the process according to claims 1 to 5 and spherically shaped telomerizate particles with an average particle diameter of 0.01 to 0.5 μ and with a narrow size distribution, expressed by the value \ d \ / 2; d _m , < 0.35. entail. 7. fluorocarbon wax powder with an average molecular weight in the range from 10,000 to 200,000. Characterized in that they have been prepared by the process of claims 1 to 5 and have an average particle size of the fine grain of 0.5 to 6 μ, wherein These primary grain particles are more than 70% associated with a loose, grape-shaped composite of 10 to 20 μm diameter, furthermore that they have a grain distribution of the primary grain, expressed by the size \ d 1 / 2.'J _111. , of < 0.9, a specific surface area of the powder, measured by the BF.T method, from 10 to 26 nr g. have a total pore volume of 80 to 120 cm ^J 100 g dry substance, a crystalline amorphous transition temperature of 270 to 325 and an apparent melt viscosity of 0.7 · 10 ² to 1 · 10 "poise at 380 ° C and 200 kp enr.