DE1124242B - Process for the polymerization of polymerizable halogen-containing monomeric compounds - Google Patents

Description

In the polymerization of vinyl compounds, acyl peroxides are known to be widely used for activation. The nature and constitution of the peroxides have a strong influence on the rate of polymerization and the properties of the polymers. The use of hydrogen-free peroxides has been known for some time, the use of which is particularly recommended for some monomers, such as trifluorochloroethylene. It was z. B. trifluorochloroethylene polymerized with Trichloracetylperoxyd at temperatures from -17 to -20 ⁰ C. In addition to the low polymerization temperatures, relatively long polymerization times are also required. The polymerization of trifluorochloroethylene with perfluorinated diacyl peroxides is also described. However, the sales achieved at low temperatures are very low. Furthermore, a propionyl peroxide is known which contains F and Cl at the same time. It can be seen from the curves given that products with a high NST value are only obtained when the catalyst is used in amounts of 0.0075%. At these low concentrations the conversions are also very poor.

A process has now been found for the polymerization of polymerizable halogen-containing monomeric compounds in an aqueous medium, in which the catalyst used is a diacyl peroxide whose acyl groups carry at least 4 carbon atoms and, apart from the end groups, the groups - CF ₂ - and - CFCl - in alternating order contain.

The process according to the invention is particularly advantageous for homopolymerization and copolymerization to carry out of trifluorochloroethylene.

There are polymers with a higher molecular weight than in the known processes cited above obtained, or the polymers can be prepared in a shorter reaction time than before. A An essential characteristic of the fluorine- and chlorine-containing acyl peroxides used is the arrangement of the Halogen atoms in the acyl radicals. The acyl peroxides used according to the invention are derivatives of largely Η-free fluorocarboxylic acids with essentially the following constitution:

The acyl chain end is formed by a CCl ₂ F or a CC1F ₂ group; the middle chain links alternately have the constitution> CF ₂ and -CFCl.

The acids are produced by oxidation at between 90 and 130 ° C at 1 mm pressure boiling fraction of a cracking oil from polytrifluorochloroethylene with potassium permanganate. You can Polymerization process

of polymerizable halogen-containing

monomeric compounds

Applicant:

Farbwerke Hoechst Aktiengesellschaft

formerly Master Lucius & Brüning,

Frankfurt / M., Brüningstr. 45

Dr. Michael Lederer, Frankfurt / M.-Unterliederbach, Dr. Edgar Fischer, Frankfurt / M.,

and Dr. Hans-Helmut Frey,

Frankfurt / M.-Unterliederbach,

have been named as inventors

also produced by telomerization of trifluorochloroethylene and subsequent saponification or oxidation. The acids have at least 4 carbon atoms; acids with 4 to 12 carbon atoms are preferred. The one used to manufacture the peroxides required acid chlorides from the acids z. B. in the following way won:

1384 parts by weight of crude fluorochlorocarboxylic acid are diluted with 510 parts by weight of phosphorus oxychloride and added dropwise to 793 parts by weight of phosphorus pentachloride with stirring. The temperature rises under evolution of HCl at about 42 ° C. After complete addition, the mixture is heated for about 2 hours at 100 to 105 ° C (internal temperature) (oil bath about 13O ⁰ C) until H Cl-cleavage is completed. After cooling, the reaction solution is suctioned off through a filter (e.g. glass or polyvinyl chloride filter) and introduced into the filtrate in order to destroy the excess pentachloride SO ₂ . The thionyl chloride formed and the PO Cl _{3 are} distilled off at normal pressure. The mixture of the crude acid chlorides is subjected to fractional vacuum distillation. 1228 parts by weight of acid chlorides purified by distillation are obtained.

The preparation of the catalysts, for which no protection is claimed, takes place according to known methods by acylation of H ₂ O ₂ with the acid chlorides in the presence of HO-binding agents

209 51W445

The reaction can also be carried out in the presence of a completely chlorinated or fluorinated solvent, for example CCl ₄ , C ₂ Cl ₃ F ₃ , CCl ₃ F, C ₄ F ₆ Cl. Partially halogenated carbon

Substances, e.g. pyridine, NaHCO ₃ or NaOH. It The peroxides are used in an amount accordingly

can also the alkali salts of H ₂ O ₂ , z. B. Na ₂ O ₂ 0.0001 to 0.1, preferably 0.0007 to 0.02 weight or BaO ₂ can be used. The conversion of active oxygen, based on the monomer, takes place at temperatures between -30 and +35 ⁰ C, used.

preferably -10 and +8 ⁰ C, in the aqueous phase. 5 However, it is not to be used on trifluorochloride

ethylene restricted. You can z. B. also polymerize vinyl chloride, vinylidene chloride, sym. Dichlorethylene, tetrafluoroethylene and vinylidene fluoride with it. The polymerization can be used in suspension or in hydrogen, for example CHCl ₃ . Carry out in io emulsion.

In these cases, the solvent is after the combination with suitable reducing agents

Production distilled off, possibly in vacuo. The agents can be the catalysts based on the peroxides principle but can also be used in solution for redox polymerization,
will. With the catalysts described here you can

The compounds can be used at temperatures below 15 polymers, which are characterized by excellent mechanical properties. 10 ° C can be stored without significant niche values, great clarity, excellent thermal decomposition entry. Compared to thermal bean stability, good processability and a large They are very sensitive to this. For example, resistance to embrittlement distinguish, manufactured a compound that breaks down from acids with 5 carbon atoms.

was produced, at 15 ° C in the course of 6 hours 20 The subject of German patent 1 030 563 is a to half the initial concentration of peroxide. Process for the production of Trifluorchloräthylen-Nach 28 hours is the active oxygen on a polymer in the presence of a halogenated acyl quarter the initial value dropped, peroxyds with at least 6 carbon atoms in the

This leads to the choice of the polymerisation temperature molecule.

rature. Has for the preparation of high molecular weight product 25 with respect to this work, the erfindungsdukten is polymerized between -5 and +35 ⁰ C, according to method has the advantage that it permits the preparation, preferably between 0 and 1O ⁰ C. At higher polymers having higher values NST At temperatures, the conversions are lower, since one takes place, the respective NST values also causing a great deal of decomposition of the catalysts, with no more polymerization being effected, which is less dependent on the catalyst concentration. One can be in 30 and on sales.

Such cases the catalyst in the course of poly- Furthermore was in the USA. patents

continuously admit merization. The chain length 2 600 804, 2 600 821 and 2 700 662 already in front High polymers is highly dependent on the beaten, trifluorochloroethylene in the presence of Catalyst concentration. When using Kata catalysts such as heptafluorobutyryl peroxide, bislysers different molecular weights it is 35 trifluoroacetyl peroxide, bis-trichloroacetyl peroxide, the concentration on the fluorochloroacetyl peroxide and dichlorofluoroacetyl peractive To obtain oxygen. oxide to polymerize. When using such

From Table 1, the relationship between peroxides is however the strength of the ^s l% when using the specific viscosity. Solutions of polytrifluorochloroethylene catalysts to be used according to the invention in 2,5-dichlorobenzotrifluoride were far from targeting reaction rates

achieved. In addition, the polymers obtained by the process according to the invention have a much higher melt viscosity than those obtained with the aid of the above-mentioned catalysts 45 were made.

Furthermore, the German patent 1 053 182, which compared to the present invention is an older Right represents a process for the polymerization and interpolymerization of at least 1 chlorine-50 atom and 1 fluorine atom containing, completely halogen-substituted ethylenes, in which as catalysts Mixtures of bis (perhaloacyl) peroxides made from oxidized polytrifluoroethylene are used The polymerization is carried out either in block or in a solvent will. The method according to the invention is in contrast carried out exclusively in the aqueous phase. This procedure permits the bulk polymerization an easier mastery of the

and the catalyst concentration can be seen. Table 1

Molecular O-active, ¹ ) tlspec sales attempt weight
of (%) Peroxydes 0.001 7.01 14th 1 around 958 0.002 3.97 22nd 2 around 958 0.0067 2.61 28 3 around 958 0.0084 2.51 50 4th around 958 0.0012 7.8 17th 5 about 558 0.0025 1.86 21 6th about 558

in percent by weight, based on the monomeric trifluorochloroethylene used.

Experiments 1 to 4 were done with a catalyst
of molecular weight about 958 performed while
in 5 and 6 such a polymerization process of molecular weight 558 60, in particular the use of heat. The polymerization temperature was dissipation, and compared to the polymerization + 4 ° C. in solvents it is significantly simpler and more economical.

These figures show that not only the more concise perform.

tration of the catalyst, but also the chain '"· ■ · ,,

₆ Example 1

100 parts by weight of trifluorochloroethylene are mixed with a peroxide of C ₅ acid (produced by the oxidative degradation of a cracking oil from polytrifluorochloro

length of the starting acid is important.

The catalysts mentioned are particularly suitable for polymerization and copolymerization of trifluorochloroethylene.

ethylene) in an amount corresponding to 0.0025 parts by weight of active oxygen in the presence of 150 parts by weight of water containing 0.16 parts by weight of Na ₈ HPO ₄ , polymerized in a rocking bomb at 4 ° C. After 41 hours, 21 parts by weight of polymer with a specific viscosity of 1.86 are obtained.

Example 2

100 parts by weight of vinyl chloride are polymerized with the catalyst used in Example 1 in an amount corresponding to 0.0011 parts by weight of active oxygen at 15 ° C. in the presence of 200 _{parts by weight of water and 0.12 parts by weight of Na 2} HPO ₄ in a stirred autoclave. After 22 hours, 39 parts by weight of polyvinyl chloride with a specific viscosity of 8.8 are obtained.

Example 3

100 parts by weight of trifluorochloroethylene (the as the one described in Example 1 is prepared in a similar way, and a similar structure having) with one of C, acid peroxide produced in an amount corresponding to 0.002 parts by weight of active oxygen at 4 ⁰ C in the presence of 150 parts by weight of water and 0.16 parts by _{weight Na 2} HPO _{4 polymerized.} After 40 hours, 22 parts by weight of polymer with a specific viscosity of 3.97 are obtained. wart of 200 parts by weight of water and 0.12 _{parts by weight of Na 2} HPO ₄ polymerized in a stirred autoclave. After 22 hours, 38 parts by weight of polyvinyl chloride with a specific viscosity of 7.33 are obtained.

Claims (3)

PATENT CLAIMS: 1. A process for the polymerization of polymerizable halogen-containing monomeric compounds in an aqueous medium in the presence of a halogenated acyl peroxide as catalyst, characterized in that the catalyst used is a diacyl peroxide whose acyl groups carry at least 4 carbon atoms and, apart from the end groups, the groups —CF ₂ - and - CF Cl - included in alternating order. 2. The method according to claim 1, characterized in that diacyl peroxides of the specified Constitution used whose acyl groups consist of fluorochlorocarboxylic acid residues with 4 to 12 carbon atoms have a uniform or mixed structure. 3. The method according to claim 1 and 2, characterized in that one fluorine-containing monomers Vinyl compounds, especially trifluorochloroethylene, or mixtures of monomers, the trifluorochloroethylene contain, polymerized. Example 4 100 parts by weight of vinyl chloride are dissolved in 0.5 parts by weight of 1-dichloromonofluoro-2-monochlorodifluoroethane in an amount corresponding to 0.0007 parts by weight of active oxygen at 15 ^° C.
U.S. Patents Nos. 2,600,804, 2,600,821,
2,700,662; 2,705,706; Kainer, Franz, polyvinyl chloride and vinyl chloride copolymers, 1951, pp. 30 to 36. Legacy Patents Considered:
German patents No. 1 030 563, 1 053 182. © 209 510/445 2.62