GB1559599A - Aromatic polyether sulfones containing nitrogen containinggroups - Google Patents

Description

(54) AROMATIC POLYETHER-SULFONES CONTAINING NITROGEN-CONTAINING GROUPS (71) We, BASF AKTIENGESELLSCHAFT, a German Joint Stock Company of 6700 Ludwigshafen, Federal Republic of Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement :- The present invention relates to new aromatic polyethersulfones containing nitrogen-containing groups, and to a process for their manufacture.

Polymers with aromatically bonded sulfone groups are disclosed in J. Chem. Soc.

(1961), 1,604-1,610, J. Polymer Sci. 40 (1959), 399-406 and U. S. Patent 2,060,715. Film-forming sulfone polymers with oxygen atoms and/or sulfur atoms as bridge members in the polymer chain are disclosed m German Published Application DAS 1,520,131. 1'hese polymers have the disadvantage that they contain certain functional groups or bonds which cause them to be sensitive to the action of acids or alkalis and of numerous organic chemicals and solvents at high temperatures, or that their degree of polymerization is too low, or that they are excessively cross-linked or highly crystalline, so that they do not exhibit the properties required for good thermo- plasticity.

The products are manufactured either by Friedel-Crafts condensation of arylsulfonyl halides with an aromatic compound, with elimination of halohydrocarbons, by the method of British Patents 1,060,546,1,109,842 and 1,163,332, by condensing dialkali metal salts of a bisphenol and an aromatic dihalogen compound by the method of German Laid-Open Application DOS 1,545,106 or 1,779,748, or by condensing the alkali metal salt of a halophenol, with elimination of an alkali metal halide, as disclosed in German Laid-Open Application DOS 1, 620, 923 or 1,795,725.

As has already been stated, the products admittedly have good heat resistance but are not resistant to a plurality of chemicals and of organic solvents, and to acids and bases, so that their possible uses are greatly restricted.

Aromatic polyamides containing sulfone groups and/or ether groups have already been disclosed in Canadian Patent 865, 810 and in Netherlands Patent 6,900,675, but these do not exhibit good heat resistance and good mechanical properties and furthermore have to be manufactured from expensive carboxylic acid chlorides, which are difficult to handle.

The present invention seeks to provide high quality polyether-sulfones, which possess not only good mechanical properties but also improved resistance to solvents and chemicals, from new, simple and inexpensively obtainable monomers.

According to the present invention there are provided aromatic polyether-sulfones containing, preferably consisting of a chain of, from 10 to 500, preferably from 30 to 100, nitrogen-containing units of the formula (I)

where the radicals Y are identical or different and each Y is a divalent radical selected from-CO-NH-,-NH-CO-,-CRl=N-and-N=CRZ- ; Rl and R= are identical or different and selected from hydrogen, alkyl of 1 to 6 carbon atoms, preferably of 1 to 2 carbon atoms, and phenyl ; and Ar is selected from 1,3-phenylene, 1,4 phenylene, 4,4'-biphenylene and

where X is selected from--O--S-S-SO-,-SOs.--,-.. Cp-, -CO-NH-and-CR'=N-and R3 is selected from hydrogen, alkyl of 1 to 6 carbon atoms, preferably of 1 or 2 carbon atoms, and phenyl.

The new aromatic polyether-sulfones of the invention will suitably have as end groups hydroxyl, nitro, alkoxy of 1 to 5 carbon atoms (e. g. methoxy) or halogen, e. g. fluorine and chlorine, but especially chlorine and/or methoxy.

Aromatic nitrogen-containing polyether-sulfones which exclusively consist of units of the formula (I) and in which the end groups are predominantly, i. e. to the extent of more than 90%, preferably from 95 to 100%, selected from chlorine and methoxy, have particularly excellent properties.

The aromatic nitrogen-containing polyether-sulfones of the invention may be obtained by condensing a dialkali metal salt of bis- (4-hydroxyphenyl)-sulfone, preferably the disodium salt and especially the dipotassium salt, with a compound of the formula (II)

where Y and Ar have the above meanings, and X and X'are identical or different and are a radical which can undergo nucleophilic substitution. Examples of the latter radicals are nitro and halogen, preferably fluorine and especially chlorine.

Examples of suitable compounds of the formula (II) are: A) Reaction products of p-nitrobenzaldehyde and/or p-chlorobenzaldehyde with diamines, and B) Reaction products of p-nitroaniline and/or p-chloroaniline with aromatic dicarbonyl compounds, e. g. aromatic dialdehydes and/or diketones.

Particularly suitable and preferentially used compounds are C) Reaction products of p-nitroaniline and/or p-chloroaniline with dicarboxylic acid chlorides, and especially D) Reaction products of p-nitro-and/or p-chloro-benzoyl chloride with aromatic diamines.

The following may be mentioned as specific examples : With respect to A): compounds of the formulae III-XIV

With respect to B): compounds of the formulae XV and XVI

With respect to C): compounds of the formulae XVII-XXII

and with respect to D): compound of the formulae XXIII-XXXIV

The compounds of the formulae III to XXXIV may be used individually or as mixtures, and in the latter case the mixing ratio may vary within wide limits, for example corresponding to a molar ratio of from 99: 1 to 1: 99, especially from 75 : 25 to 25 : 75.

To manufacture the new aromatic polyether-sulfones, containing nitrogen groups, a dialkali metal salt of bis- (4-hydroxyphenyl)-sulfone and a compound, or mixture of compounds, of the formula II are condensed in the molar ratio of from 0.9 to 1. 1 : 1, preferably from 0.97 to 1.05: 1 and especially about 1: 1.

The condensation is carried out at from 120 C. to below the decomposition temperature of the reactants, preferably at from 160 to 350 C., in anhydrous media, in the absence or, preferably, in the presence of solvents. Solvents which have proved particularly suitable are polar aprotic compounds, eg. dimethylformamide, dimethylacetamide, N-methylpyrrolidone and, preferably, dimethylsulfoxide and 1,1-dioxotetrahydrothiophene (sulfolan). If solvents are used, their amounts are advantageously such that the resulting solutions of the polyether-sulfones containing nitrogen-containing groups have a solids content of from 20 to 70% by weight, preferably from 40 to 60% by weight and especially about 50% by weight.

Suitable molecular weight regulators are halohydrocarbons, eg. methyl chloride.

If these are added after the desired molecular weight has been reached, the phenolate end groups of the bis- (4-hydroxyphenyl)-sulfone, present in the condensation mixture, are converted to alkoxy groups. This stops further condensation.

The manufacture of the new aromatic polyether-sulfones containing nitrogen groups is preferably carried out as follows: The dipotassium salt of bis- (4-hydroxvphenyl)-sulfone, which can be obtained from potassium hydroxide and bis- (4-hydroxyphenyl)-sulfone by conventional methods, is condensed with an approximately equivalent amount of a compound of the formula (II) at above 120 C., preferably at from 160 C. to 350 C., in the presence of an aprotic solvent. After the desired molecular weight has been reached, the polycondensation is stopped by adding methyl chloride. The salt formed during the polycondensation is separated from the polymer, preferably by filtration or extraction. The polyether-sulfone of the invention may be further processed by using the solution directly, to form fibers, films, coatings and laminates. However, it can also be converted to a solid by precipitation, preferably with water and/or low molecular weight alcohols, eg. methanol and isopropanol, followed by drying, and this solid can be processed by compression molding, extrusion or injection molding, to give shaped articles.

The new polyether-sulfones, containing nitrogen-containing groups, are in general resistant to heat distortion up to 240 C. and in general have viscosities corresponding to q,. h from 25 to 0.70 ; they are used preferentially for the manufacture of films for the electrical industry and shaped articles for electrical equipment, household utensils and automobiles.

The Examples which follow illustrate the invention. Parts are by weight. The inherent viscosities thab were measured at 24 C. and calculated from the equation In rel q= ~ C Possession of an inherent viscosity in the range from 0.25 to 0.70 in the Examples indicates that the aromatic polyether-sulfones produced contain between 10 and 500 units of the formula (I).

Manufacture of the starting monomers of the general formula (II).

1.4,4'-Di- (p-chlorobenzoylamino)-diphenyl ether (XXVI).

700 parts of 4-chlorobenzoyl chloride are added to a solution of 400 parts of 4,4' diarnino-d. phenyl ether in 2,000 parts of N-methylpyrrolidone whilst stirring at room temperature. After the main reaction has subsided, the reaction solution is stirred for 2 hours at 120 C. and a large amount of water is then added. On filtering off and drying the product, colorless 4,4'-di- (p-chlorobenzoylamino)-diphenyl ether (of the formula (XXVI)) having a melting point of 336-337 C., is obtained in almost quantitative yield.

If the procedure described under 1) is followed, but using the starting materials shown in the Table, the starting monomers 2)-5) listed in the Table are obtained.

6.4,4'-[N, N'-di-(p-chlorobenzylidene)]-diamino-diphenyl ether (VI) A mixture of 400 parts of 4,4'-diamino-diphenyl ether, 562 parts of 4-chlorobenzaldehyde and 5 parts of concentrated hydrochloric acid in 2,500 parts of toluene is heated under reflux in a conventional esterification apparatus until the theoretical amount of water has been distilled off azeotropically. On cooling the reaction solution, the end product of crystallizes out and can be filtered off and dried. 880 parts of 4,4' [N, N'-di- (p-chlorobenzylidene)]-diamino-diphenyl ether having a melting point of 231 235 C. are obtained.

7.4,4'-[N, N'-di-(p-chlorobenzylidene)]-diamino-diphenyl-methane (IV) If the procedure described under 6) is followed, but with 396 parts of 4,4'diamino-diphenylmethane and 562 parts of 4-chlorobenzaldehyde as starting materials, 880 parts of 4,4'- [N, N'-di-(p-chlorobenzylidene)]-diamino-diphenylmethane of the formula IV, having a melting point of 178 -179 C., are obtained. manufactured from Starting monome@ Melting Yield, Starting and Starting Type point C Formula parts material parts material parts # 2 4,4'-di-(p-nitro- 268-270 XXIII 988 4,4'-diamino- 396 4-nitrobenzoyl 742 benzoylamino)-di- diphenylmethane chloride phenylmethane 3 4,4'-di-(p-chloro- 310-312 XXIV 940 4,4'-diamino- 396 4-chlorobenzoyl 700 benzoylamino)-di diphenylmethane chloride phenylmethane 4 1,4-di-(-chloro- 350 XXXII 740 p-phenylenediamine 216 4-chlorobenzyol 700 benzoylamino)- chloride benzene 5 terephthalic acid 290-293 XX 750 4-chloroaniline 510 terephthalic 406 di-(p-chloroanilide) acid dichloride 8. Dipotassium salt of 4,4'-dihydroxydiphenyl-sulfone 561 parts of a 50** strength by weight aqueous potassium hydroxide solution are 561 parts of a 50% strength by weight aqueous potassium hydroxide solution are 1,1-dioxotetrahydrothiophene and 3,000 parts of chlorobenzene at 60 C., whilst stirring. All the water is then distilled off azeotropically with the aid of chlorobenzenc.

After distilling off the remaining chlorobenzene, a solution of the dipotassium salt of 4,4'-dihydroxydiphenylsulfone in 1,1-dioxotetrahydrothiophene is obtained, which is used for the further polycondensation.

EXAMPLE 1.

954 parts of 4,4'-di-(p-chlorobenzoylamino)-diphenyl ether are added to a solution, freshly prepared as described in 8), of the dipotassium salt of 4,4'-dihydroxydiphenylsulfone in 1,1-dioxotetrahydrothiophene, at 160 C., whilst stirring; the reaction mixture is then slowly heated to 220 C. and the condensation is carried out at this temperature for 6 hours. After cooling the reaction mixture, the resulting polyether-sulfone containing nitrogen-containing groups is precipitated with water, filtered off and dried. The polycondensate has a viscosity of **mh = 0.26, exhibits excellent heat resistance and is insoluble in the conventional solvents.

EXAMPLE 2.

By following the method described in Example 1, but using, in place of 4,4'-di (p-chlorobenzoylamino)-diphenyl ether, 992 parts of 4,4'-di-(p-nitrobenzoylamino)diphenylmethane, a polyether-sulfone containing nitrogen-containing groups and having a viscosity of **mh=0.45 is obtained, which exhibits good heat resistance and insoluble in the conventional organic solvents.

EXAMPLE 3.

By following the method described in Example 1, but using, in place of 4,4'-di (p-chlorobenzoylamino)-diphenyl ether, 950 parts of 4,4'-di-(p-chlorobenzoylamino)diphenylmethane as the starting monomer, a polyether-sulfone containing nitrogencontaining groups and having a viscosity of =0. 35 is obtained, which exhibits good heat resistance and is insoluble in the conventional organic solvents.

EXAMPLE 4.

Following the method described in Example 1, a solution, prepared as described in 8., of the dipotassium salt of 4,4'-dihydroxydiphenylsulfone in 1,1-dioxotetrahydrothiophene is condensed with 770 parts of 1, 4-di- (p-chlorobenzoylamino)-benzene. A polyether-sulfone containing nitrogen-containing groups and having a viscosity of 7, b=0@5 is obtained, which exhibits good heat resistance and is insoluble in the conventional organic solvent.

EXAMPLE 5.

A polyether-sulfone, containing nitrogen-containing groups, is manufactured by the method described in Example 4, from the di-potassium salt of 4,4'-dihydroxy-diphenylsulfone and 770 parts of terephthalic acid di- (p-chloroanilide). The polycondensate, which has excellent heat resistance and is insoluble in conventional organic solvents, has a viscosity of l, ob=0. 30.

EXAMPLE 6.

A polyether-sulfone, containing nitrogen-containing groups, is manufactured by condensation by the method described in Example 4, from the dipotassium salt of 4,4'dihydroxy-diphenyl-sulfone and 890 parts of 4,4'- [N, N'-di- (p-chlorobenzylidene)] diaminodiphenyl ether. The polycondensate, which exhibits excellent heat resistance and relatively good solvent resistance, has a viscosity of 7jnh=0. 60.

EXAMPLE 7.

If the method described in Example 4 is followed but instead of 1, 4-di- (p-chloro benzoylamino)-benzene 886 parts of 4, 4'-[N,N'-di-(p-chlorobenzylidene)]-diaminodiphenylmethane are used, a polyether-sulfone containing nitrogen-containing groups and having a viscosity of t b=0. 53 is obtained, which possesses good heat resistance and is relatively sparingly soluble in conventional organic solvents.

To test the solubility in conventional organic solvents, the new aromatic nitrogencontaining polyether-sulfones and diphenyl ether-sulfones, which contain units of the formula

and 2,2- (4, 4'-dihydroxy-diphenyl)-propane-diphenylsulfones, which contain units of the formula

are suspended, in the form of powders, in methylene chloride and the suspension is stirred for 24 hours at room temperature. It is found that polymers based on diphenyl ether-sulfones and 2,2- (4, 4'-dihydroxydiphenyl)-propane-diphenylsulfone (Comparative Examples) dissolved completely in methylene chloride, whilst the polymers according to the invention, manufactured as described in Examples 6 and 7, were only partially soluble and those manufactured as described in Examples 1 to 5 were completely insoluble.

Claims (7)

1. WHAT WE CLAIM IS :- 1. An aromatic polyether-sulfone containing from 10 to 500 nitrogen-containing units of the formula I

   where the radicals Y are identical or different and each Y is a divalent radical selected from-CO-NH-,-NH-CO-,--CRI=N-and-N=CRZ- ; R'and R2 are identical or different and selected from hydrogen, alkyl of 1 to 6 carbon atoms and phenyl ; and Ar is selected from 1,3-phenylene, 1,4-phenylene, 4,4'-biphenylene and

   where X is selected from-O-,-S-,-SO-,-SOZ-,-CO-O-, -CO-NH-and-. CR'=N-and R'is selected from hydrogen, alkyl of 1 to 6 carbon atoms and phenyl.
2. 2. An aromatic polyether-sulfone consisting of a chain of the formula (Ia)

   where Y, Ar, R', R2, R'and X have the meanings given in claim 1 and n is an integer of from 10 to 500, terminated by end groups selected from F, Cl, methoxy and nitro.
3. 3. A process for the manufacture of an aromatic polyether-sulfone as claimed in daim 1, wherein a dialkali metal salt of bis- (4-hydroxyphenyl)-sulfone is condensed with a compound of the formula II

   where Y and Ar have the meanings given in claim 1 and X and X'are identical or different and each is fluorine, chlorine or nitro, at from 120 C. to below the decomposition temperature of the reactants.
4. 4. A process as claimed in claim 3, wherein a dialkali metal salt of bis- (4- hydroxyphenyl)-sulfone is condensed with a compound of the formula II in a molar ratio of from 0. 9: 1 to 1.1: 1.
5. 5. A process as claimed in claim 3 or 4, wherein the condensation is carried out at from 160 to 350 C.
6. 6. A process for the manufacture of an aromatic polyether-sulfone containing nitrogen-containing groups carried out substantially as described in any of the foregoing Examples.
7. 7. Aromatic polyether-sulfones containing nitrogen-containing groups when manufactured by a process as claimed in any of claims 4 to 6.