IE902985A1

IE902985A1 - Multicomponent alloy having one glass transition temperature

Info

Publication number: IE902985A1
Application number: IE298590A
Authority: IE
Original assignee: Hoechst Ag
Priority date: 1989-08-19
Filing date: 1990-08-17
Publication date: 1991-02-27
Also published as: DE59008405D1; JPH03106964A; EP0414124A3; DE3927399A1; EP0414124B1; PT95021A; CA2023514A1; EP0414124A2

Abstract

Alloys of homogeneously mixed polymers, containing (a) at least one polyaryl ether ketone, (b) at least one polyimide and (c) at least one polyaryl ester, have both higher glass transition temperatures and lower melt viscosities than the polyaryl ether ketones alone.

Description

HOECHST AKTIENGESELLSCHAFT HOE 89/F 272 Dr. K/AP Description Multicomponent alloy having one glass transition temperature During recent years, a large number of publications have appeared which describe the synthesis and properties of polyaryl ethers. One of the earliest works is concerned with the electrophilic aromatic substitution of aromatic dihalides using unsubstituted aromatic compounds such as diphenyl ethers (US-A-3,065,205). Johnson and co-workers (Journal of Polymer Science, A-l, 5, 1967, 2,415 - 2,427; US-A-4,107,837 and 4,175,175) describe nucleophilic aromatic substitutions (condensations). This synthetic pathway led to a new category of polyaryl ethers, the polyaryl ether ketones.

In recent years interest in polyaryl ether ketones has increased, as is shown by the appearance of a number of publications: US-A-3,953,400; 3,956,240; 4,247,682; 4,320,224; 4,339,568; Polymer, 1981, 22, 1,096 - 1,103; Polymer, 1983, 24, 953 - 958.

Several polyaryl ether ketones are already commercially available, for example those having the following structure: (PEK) (PEEK) Polyaryl ether ketones are also well known. These are a valuable category of polymers having excellent properties. In particular, they have high heat resistance, hydrolysis resistance and good solvent resistance. Some polyaryl ether ketones are highly crystalline and have melting points far in excess of 300°C. It is possible to synthesize polyaryl ether ketones having different melt temperatures and molecular weights.

For some applications, for example as matrix materials for composites, higher glass transition temperatures and lower melt viscosities are desirable. Consequently, it is of great industrial interest to suitably modify polyaryl ether ketones to give, on the one hand, higher glass transition temperatures and, on the other hand, improved melt processibility. Furthermore, it is desirable that the properties of the polyaryl ether ketones and of the modified polyaryl ether ketones, for example water absorption or impact strength, are at a comparable level.

It is known that technologically important properties of polymers, for example of those mentioned above, can be imparted by alloying polymers with other polymers. The resulting alloys can be classified into two fundamentally different categories. The non-homogeneously mixed category of alloys are multiphase and usually have a plurality of glass transition temperatures. The homogeneously mixed category of alloys are single-phase and normally have a single composition-dependent glass transition temperature. These alloys having a single compositiondependent glass transition temperature are referred to in the subsequent text by the term homogeneously mixed.

In this connection, there is particularly great industrial interest in alloys of homogeneously mixed polymers, since the technological properties of these alloys can be selec-tively adapted to defined requirements by varying the com-ponents and the mixing ratios (Olabisi, Robeson, Shaw: Polymer-Polymer Miscibility, Academic Press, New - 3 York 1979).

However, it has not been remotely possible hitherto to safely predict, from the properties of the individual components, the homogeneous miscibility and the proper5 ties of an alloy. Consequently, the alloying of polymers remains substantially empirical. In particular, the homogeneous miscibility of the components in alloys remains unpredictable despite a very large number of experimental and theoretical studies in this field.

For instance, it is known that alloys of homogeneously miscible polymers are rare (Journal of Polymer Science, Polymer Physics Edition, Vol. 21, p. 11, 1983). In Macromolecules, Vol. 16, p. 753, 1983, it is stated that the number of blend systems which are known to be homo15 geneously miscible has increased in the last decade.

However, until now modern theories have had only limited success in predicting miscibility. Consequently, there is some doubt that it is possible to develop any practical theory to take account of the actual complexities of polymer-polymer interactions which result from natural phenomena.

In contrast, the methods for the experimental determination of miscibility are known (Olabisi, Robeson, Shaw: Polymer-Polymer Miscibility, Academic Press, New York, p. 321-327, 1979): the most important criterion for homogeneous miscibility is the existence of a single glass transition temperature which is intermediate between those of the components used to prepare the mixture. The transparency of polymer alloys in the melt and, insofar as these are not partly crystalline, in the solid, is an indication that the components are homogeneously mixed.

Alloys of polyarylates with polyimides, which may additionally contain a thermoplastic polymer, have already been described (US-A-4,250,279). The amount of this third component is only at most 40 percent by weight. The advantage of these three-component mixtures is supposed to be that they have an acceptable balance of mechanical properties. Values for the combination with polyaryl ether ketones, which would provide a standard, are not to be found in this publication. Neither does the publication mention that the alloys described in the present invention are homogeneously miscible within a wide range of concentration and have not only increased glass transition temperatures but also lower melt viscosities than the polyaryl ether ketones alone.

Binary miscible alloys of a polyaryl ether ketone and specific polyimides have likewise been disclosed (EPA-0,257,150). This publication states that the addition of a polyaryl ether ketone improves the melt processibility of the polyimide. However, the applicant's own experiments have shown that the flowabilities of these alloys (MFI) are either not significantly better, or even worse, than those of the polyaryl ether ketones alone. However, it is noteworthy that the melt viscosities during processing, i.e. at 360°C, are still inconveniently high. In contrast, the multicomponent alloys according to the invention have flowabilities which are significantly better than those of polyaryl ether ketones and those of the binary alloys of the above-cited EP patent specification.

The object of the present invention is therefore to provide alloys based on homogeneously mixed polyaryl ether ketones and other polymers, having an increased glass transition temperature and improved melt processibility, in particular for the preparation of composites .

Surprisingly, it has now been found that polyaryl ether ketones are homogeneously miscible together with polyaryl esters and polyimides within a wide concentration range and give alloys which not only have higher glass transIE 902985 ition temperatures but also lower melt viscosities than the polyaryl ether ketones alone.

The present invention accordingly provides alloys of homogeneously mixed polymers containing (a) at least one polyaryl ether ketone, (b) at least one polyimide and (c) at least one polyaryl ester.

The individual components are used in the following amounts: polyaryl ether ketones: 45 to 98, preferably 60 to 95 and in particular 75 to 95 percent by weight; polyimides: 1 to 50, preferably 2 to 35 and in particular 2 to 20 percent by weight; polyaryl esters: 1 to 50, preferably 2 to 35 and in particular 2 to 20 percent by weight, relative in each case to the total alloy.

Polyaryl ether ketones a) which can be used in alloys according to the present invention contain one or more repeating units of the following formulae: Vc/O'x_tAr-50^x0_ in which Ar is a divalent aromatic radical selected from phenylene, biphenylene or naphthylene, and X, independently of one another, represents 0, CO or a direct bond, n is zero or is, as an integer, 1, 2 or 3; b, c, d and e are zero or 1, a is, as an integer, 1, 2, 3 or 4 and d is preferably zero, if b is equal to 1. Preference is given to polyaryl ether ketones having repeating units of the following formulae: These polyaryl ether ketones can be synthesized by known methods which have been described in CA-A-847,963; US-A-4,176,222 ; US-A-3,953,400; US-A-3,441,538; US-A-3,442,857; US-A-3,516,966; US-A-4,396,755 and US-A-4,398,020.

The term polyaryl ether ketones in this context includes homopolymers, copolymers, terpolymers and block copolymers .

The polyaryl ether ketones have intrinsic viscosities of 5 0.2 to 5, preferably of 0.5 to 2.5 and particularly preferably of 0.7 to 2.0 dl/g, measured in 96 % strength sulfuric acid at 25*C.

The alloys according to the invention contain poly- imides b) having repeating units of the following 10 formula: 0 II 0 li II 0 li 0 in which R1 is selected from (a) a substituted or unsubstituted aromatic radical of the following formulae or {β) a divalent radical of the general formula < R3 > 0-4 (r3)q_4 in which R3 represents Ci-Ce-alkyl or halogen and R* represents -0-, -S-, -CO-, -S02-, -SO-, alkylene and alkylidene each having 1 to 6 carbon atoms or cycloalkylene and cycloalkylidene each having 4 to 8 carbon atoms. The indices 0-4 in the case of R3 denote the integers zero, one, two, three or four. - 9 R2 is an aromatic hydrocarbon radical having 6 to 20, preferably 6 to 12 carbon atoms, or a halogen- or alkylsubstituted derivative thereof, the alkyl group containing 1 to 6 carbon atoms, or an alkylene or cycloalkylene radical having 2 to 20, preferably 2 to 6 carbon atoms or a divalent radical of the formula <£3>0-4 <£3>0-4 in which R3 and R* are as defined above and R* may also be a direct bond.

Other polyimides which are suitable for the purposes of 10 the invention include those having repeating units of the formula o 11 r c c -O-Z7 XN-R2-NZ Vo-R1•I λ 0 in which R1 and R2 are as defined above, 5>0-o-z representing -o in which R5, independently of one another, is hydrogen, 15 alkyl or alkoxy, each having 1 to 6 carbon atoms in the alkyl radical (here also, the index 0-3 represents the integers zero, one, two or three), or is ι Ο -Ο in which the oxygen is linked with one of the rings and is in the ortho- or para-position relative to one of the bonds of the imide carbonyl group.

Preferred polyimides according to the invention are those having the following repeating units The term polyimides in this context includes homopolymers , copolymers, terpolymers and block copolymers. The polyimides used have intrinsic viscosities of 0.1 to 3, preferably of 0.3 to 1.5 and in particular of 0.3 to 1 dl/g, measured at 25°C, for example in N-methylpyrrolidone or methylene chloride.

The polyimides which are used according to the present invention are known. Their synthesis has been described, for example in US-A-3,847,867; 3,847,869; 3,850,885; 3,852,242; 3,855,178; 3,887,558; 4,017,511; 4,024,110 and 4,250,279.

The polyaryl esters c) may be polyester carbonates, whose syntheses have been described for example in US-A-3,030,331; 3,169,121; 4,194,038 and 4,156,069. These are copolyesters containing carbonate groups, carboxylate groups and aromatic groups, at least some of the carboxyl groups and at least some of the carbonate groups being bonded directly to the ring carbon atoms of the aromatic groups. These polymers are usually prepared by reacting difunctional carboxylic acids with dihydroxyphenols and carbonate precursors.

Dihydroxyphenols for the synthesis of polyester carbonates which are suitable for the present invention have the general formula Γ 1 Ί Γ* -r 1 Ί O _ — H —- L. s in which A is an aromatic group such as phenylene, biphenylene or naphthylene and E is selected from alkylene or alkylidene, such as methylene, ethylene or isopropylidene. E may also be composed of two or more alkylene or alkylidene groups linked by a non-alkylene or non-alkylidene group such as, for example, an aromatic group, a tertiary amino group, a carbonyl group, a sulfide group, a sulfoxide group, a sulfone group or an ether group. E may also be a cycloaliphatic group, a sulfide group, a sulfoxide group, a sulfone group, an ether linkage or a carbonyl group.

R is selected from hydrogen, an alkyl group (Cx-C3), an aryl group (C6-C12) or a cycloaliphatic group. Y may have the meaning of R or be a halogen or a nitro group, s, t and u, independently of one another, are zero or 1. m and p, independently of one another, are zero or an integer which is of the same magnitude as the maximum number of substituents which A or E can carry.

If a plurality of the substituents denoted by Y are present, these may be identical or different. The same is true for R. The hydroxyl groups and Y can be linked para-, meta- or ortho-positions on the aromatic radicals.

Preferred dihydroxyphenols for the preparation of the polyaryl esters c) are those of the formula < Y' (R in which 7' is alkyl having 1 to 4 carbon atoms, cycloalkyl having 6 to 12 carbon atoms or halogen, preferably chlorine or fluorine. Each m', independently of one another, is zero, 1, 2, 3 or 4, preferably zero, and R' is alkylene or alkylidene each having 1 to 8, preferably 1 to 4 carbon atoms or an arylene radical having 6 to 20, preferably 6 to 12 carbon atoms, in particular alkylidene having 3 carbon atoms. The index ”0-1 denotes zero or 1.

The dihydroxyphenols can be used alone or as mixtures of at least two dihydroxyphenols.

Aromatic dicarboxylic acids for the synthesis of polyaryl esters c) which are suitable for the present invention have the general formula: HOOC - R . cooh in which R is selected from the groups in which f is zero or 1 and W represents 0, S02, CO, C(CH3)2, CH2, S or < T)0-4 < T > 0~4 in which W' has the meaning given above for W.

In the formulae, T is selected from alkyl having 1 to 6 carbon atoms, preferably methyl, propyl or butyl, or halogen, preferably F, Cl or Br. The indices 0-4 next to T denotes the integers zero, one, two, three or four.

Preferred aromatic dicarboxylic acids are isophthalic acid, terephthalic acid or mixtures of these two. Preference is also given to the use of reactive derivatives of aromatic dicarboxylic acids such as terephthaloyl dichloride, isophthaloyl dichloride or mixtures of these two.

Suitable carbonate precursors for the synthesis of the polyester carbonates are carbonyl halides, for example phosgene or carbonyl bromide, and carbonate esters, for example diphenyl carbonate.

Moreover, the alloys according to the invention may contain polyaryl esters which have been derived from at least one of the abovementioned dihydroxyphenols and at least one of the abovementioned aromatic dicarboxylic acids or reactive derivatives thereof.

These polyaryl esters can be prepared by one of the wellknown polyester-forming reactions, for example by reacting acid chlorides of aromatic dicarboxylic acids with dihydroxyphenols or by reacting aromatic di-acids with di-ester derivatives of dihydroxyphenols or by reacting dihydroxyphenols with aromatic dicarboxylic acids and diaryl carbonates. Reactions of this type are described, for example, in US-A-3,317,464; 3,395,119; 3,948,856 3,780,148; 3,824,213 or 3,133,898.

As is well-known, these polyaryl esters are less heat stable than the other components of the alloys according to the invention. Consequently, the proportions by weight of polyaryl esters of this type are preferably low in those alloys which contain polyaryl ether ketones of particularly high melting points, for example the one having the repeating units given below.

However, since the abovementioned polyester carbonates are more heat stable than the other polyaryl esters which have been described in the present text, preference is given to the use of these polyester carbonates as polyaryl esters c) with the abovementioned polyaryl ether ketones of particularly high melting points for the preparation of an alloy according to the invention.

The polyaryl esters or polyester carbonates used have intrinsic viscosities of 0.1 to 2, preferably 0.3 to 1.5 and in particular 0.3 to 1 dl/g, measured at 25*C in pchlorophenol, methylene chloride or N-methylpyrrolidone. The term polyaryl esters in this context includes homopolymers, copolymers, terpolymers and block copolymers.

The homogeneous miscibility of the components in the alloys according to the invention was proven using a plurality of the abovementioned methods.

For instance, the alloys according to the invention have a single glass transition temperature which can be identified by differential calorimetry, and moreover give transparent melts.

The alloys according to the invention are prepared by 5 known alloying methods. For instance, the alloying components in powder or granule form are processed together in an extruder to give strands and the strands are cut to give granules and these are converted into the desired shape, for example by pressing or injection molding.

The alloys may contain additives, for example plasticizers, heat stabilizers, UV stabilizers, impact modifiers or reinforcing additives such as glass fibers, carbon fibers or high modulus fibers.

The alloys can be advantageously used, in particular as matrix materials for composites since they have not only a high glass transition temperature but also good flowability. In particular, composites of the alloys according to the invention with glass fibers or carbon fibers are mechanically strong and can be prepared free of gas bubbles. Furthermore, the alloys are suitable for the production of molded articles by injection molding or extrusion, for example in the form of fibers, films and tubes.

Examples The following polymers were synthesized and used in the examples: Polyaryl ether ketone I having an intrinsic viscosity of 1.2 dl/g, measured in 96 % strength sulfuric acid at °C, and containing repeating units of the following formula: θ·°9· The polyaryl ether ketone II having an intrinsic viscosity of 1.0 dl/g, measured in 96 % strength sulfuric acid at 25eC, and containing repeating units of the following formula: The polyaryl ether ketone III having an intrinsic viscosity of 1.0 dl/g, measured in 96 % strength sulfuric acid at 25°C, and containing repeating units of the following formula: Polyimide I having an intrinsic viscosity of 0.5 dl/g, 10 measured in chloroform at 25”C, and containing repeating units of the following formula: Polyaryl ester I having an intrinsic viscosity of 0.5 dl/g, measured in methylene chloride at 25’C, and containing repeating units of the following formula: Polyaryl ester II having an intrinsic viscosity of 0.7 dl/g, measured in p-chlorophenol at 25’C, and containing repeating units of the following formula: The specified polymers were first dried (140”C, 24 h, reduced pressure) and then in varying weight ratios either kneaded in a laboratory compounder (Rheocord System 90/Rheomix 600, HAAKE, Karlsruhe, Federal Republic of Germany) under an inert gas or extruded in a laboratory extruder under protective gas (Rheocord System 90/Rheomex TW 100, HAAKE). Preference is given to the use of argon as inert or protective gas. The resulting alloys were dried (140°C, 24 h, reduced pressure) and then either injection molded to give moldings such as dumbbell test specimens or impact test specimens (6 x 4 x 50 mm) (injection molding machine: Stiibbe S55d, DEMAG, Kalldorf, Federal Republic of Germany) or tested for their physical properties. The following instruments were used for this purpose: Melt index testing apparatus MPS-D, Goettfert, Buchen, Federal Republic of Germany, and a capillary viscometer for measuring the flowabilities of the alloys.

Automatic torsion apparatus, Brabender, Offenbach, Federal Republic of Germany and a differential calorimeter DSC 7, Perkin Elmer, Oberlingen, Federal Republic of Germany, for determining the glass transition temperatures of the alloys.

Pendulum impact testing apparatus, Zwick, Nuremberg, Federal Republic of Germany, for determining Charpy (notched) impact strengths.

In the tables, V indicates a comparison.

Example 1: The polyether ketone I, the polyimide I and the polyaryl ester I were kneaded together for 30 minutes at a temperature of 360°C and a rotor speed of 100 rpm in the laboratory compounder, in various proportions by weight. Table 1 shows that the great majority of the alloys are composed of homogeneously miscible components since they not only have a single composition-dependent glass transition temperature but also give transparent melts.

Table 1; Miscibility Polyaryl ether ketone I Polyimide I (% by wt.) Polyaryl ester I No. of glass transition temps. °C Melt trans- parency V 100 % 0 0 % one 142 yes V 0 % 100 0 % one 217 yes V 0 % 0 100 % one 190 yes V 80 % 20 0 % one 163 yes V 50 % 50 0 % one 180 yes V 20 % 80 0 % one 201 yes 80 % 10 10 % one 153 yes 60 % 20 20 % one 160 yes 50 % 25 25 % one 180 yes V 33.3 % 33.3 33.3 % one 180 yes V 20 % 60 20 % one 185 yes V 20 % 20 60 % two no V 80 % 0 20 % one 145 yes 55 % 10 35 % one 165 yes 45 % 10 45 % one 170 yes V 40 % 20 40 % one 175 yes V 0 % 50 50 % one 195 yes V 0 % 75 25 % one 205 yes This example shows that the components of the alloys according to the invention are homogeneously miscible within a wide concentration range and have higher glass transition temperatures than the polyaryl ether ketone I alone.

Example 2: A twin-screw extruder (all four zones 360°C) was used to extrude together and granulate the polymers mentioned in Example 1 in various ratios by weight, after these polymers had been intensively dried (140°C, 24 h, reduced pressure). The granules were then dried under reduced pressure at 140°C for 24 hours and used for measurements of the flowability of the alloys. Table 2 gives the resulting MFI values (melt index in accordance with DIN 53735-MFI-B, 360°C) and the melt viscosities measured using a capillary viscometer (2 shear rates).

Table 2: Flowability Polyaryl Polyimide I (% by wt.) Poly- aryl ester MFI (360°C) I Viscosity at ether ketone I 360 C 300s'1 in Pas 120s'1 V 100 % 0 0 % 5 900 1,300 V 0 % 100 0 % 30 260 270 V 80 % 20 0 % 7 900 1,300 V 0 % 0 100 % 190 43 49 25 V 50 % 50 0 % 11 830 1,300 V 20 % 80 0 % 15 830 1,280 80 % 10 10 % 20 500 600 60 % 20 20 % 29 300 360 V 33.3 % 33.3 33.3 % 73 30 V 20 % 60 % 20 % 60 230 270 This example shows that the melt viscosities of the alloys according to the invention are significantly lower than those of polyaryl ether ketone I alone, the viscosity reduction achievable by mixing polyimide I alone with polyether ketone I being only slight. - 20 Example 3: The granules described in Example 2 were injection molded at 360°C to give impact test specimens and dumbbell test specimens, and on these the impact strengths (Charpy, notched) and the water absorption (23°C, 85 % rel. humidity, 24 h) of the alloys were measured (Table 3).

Table 3: Impact strengths and water absorption Polyaryl ether ketone I Polyimide I (% by wt.) Poly- aryl ester Water absorp- I tion in % by wt. Impact strength (mJ) V 100 % 0 0 % 0.2 110 V 0 % 100 0 % 0.51 80 15 V 80 % 20 0 % 0.24 120 V 50 % 50 0 % 0.38 115 V 20 % 80 0 % 0.43 80 80 % 10 10 % 0.23 105 60 % 20 20 % 0.27 100 20 V 33.3 % 33.3 33.3 % 0.39 95 V 20 % 60 20 % 0.46 78 This example shows that a low water absorption and impact strengths are only obtained using the alloys according to the invention which contain the individual components in amounts within the claimed limits and that these properties are comparable with those from alloys of polyaryl ether ketones with polyimides alone.

Example 4: The compounder was used at 100 rpm and 380°C to knead together for 30 minutes: polyaryl ether ketone II, polyimide I and polyaryl ester II in various compositions. Table 4 shows that the majority of the components of the alloys are homogeneously miscible since these give transparent melts and a single composition35 dependent glass transition temperature.

Table 4: Miscibility Polyaryl Poly- Poly- No. of ether imide I aryl glass ketone I (% by wt.) ester II transition temps .

Melt transparency V 100 % 0 0 % one 165 yes V 75 % 25 0 % one 170 yes 10 V 50 % 50 0 % one 205 yes V 20 % 75 0 % one 217 yes 80 % 10 10 % one 170 yes 60 % 20 20 % one 175 yes V 33. 3 % 33.3 33. 3 % one 185 yes 15 V 0 % 50 50 % one 195 yes Example 5: Films of thickness 0.3 mm were molded under reduced pressure (100 bar) at 380°C from the alloys (granules) described in Example 2. Between each pair of these sheets of film were laid commercially available webs of carbon fibers and these sandwiches were molded under reduced pressure at 380°C to give composites. Gas bubble-free composites resulted.

Example 6: Polyaryl ether ketone I, polyaryl ether ketone II, polyimide I and polyaryl ester II were kneaded together in the ratios by weight given in Table 5 in the laboratory compounder at 380°C and 100 rpm for 30 minutes. The test alloys have a single composition-dependent glass transition temperature and give transparent melts. They were therefore considered to be homogeneously mixed. - 22 Table 5: Miscibility Polyaryl Polyaryl Poly- Poly- No. of Melt ether ether imide I aryl glass trans- ketone II ketone I ester trans- parency (% by wt.) II ition temps0 C 33.3 % 33.3 6.7 % 16.7 % one 175 yes V 33.3 % 33.3 33.3 % 0 % one 180 yes 10 30 % 30 % 30 % 10 % one 180 yes Example 7: g of the polyaryl ether ketone III, 15 g of the polyimide I and 5 g of the polyaryl ester II were kneaded together in the compounder at 390 “C for 20 minutes at 100 rpm. This gave a transparent melt and the resulting alloy had a single glass transition temperature at 165*C.

Claims

1. An alloy of homogeneously mixed polymers, having one glass transition temperature and containing (a) at least one polyaryl ether ketone having an intrinsic viscosity of 0.2 to 5 dl/g, (b) at least one polyimide having an intrinsic viscosity of 0.1 to 3 dl/g and (c) at least one polyaryl ester having an intrinsic viscosity of 0.1 to 2 dl/g.

2. The alloy as claimed in claim 1, wherein the components are present in the following proportions: a) polyaryl ether ketones: 98 to 45, preferably 95 to 60 and in particular 95 to 75 % by weight, b) polyimides: 1 to 50, preferably 2 to 35 and in particular 2 to 20 % by weight and c) polyaryl esters: 1 to 50, preferably 2 to 35 and in particular 2 to 20 % by weight, relative in each case to the total alloy.

3. The alloy as claimed in claim 1 or 2, wherein the components have the following intrinsic viscosities: a) polyaryl ether ketones from 0.5 to 2.5 and in particular from 0.7 to 2.0 dl/g, b) polyimides from 0.3 to 1.5 and in particular from 0.3 to 1.0 dl/g and c) polyaryl esters from 0.3 to 1.5 and in particular from 0.3 to 1 dl/g.

4. The alloy as claimed in one or more of claims 1 to 3, wherein the polyaryl ether ketone contains repeating units of one or more of the following formulae: in which Ar is a divalent aromatic radical selected from phenylene, biphenylene or naphthylene, and X represents 0, CO or a direct bond, n is zero or is, as an integer, 1, 2 or 3; b, c, d and e are zero or 1, a is, as an integer, 1, 2, 3 or 4 and d is preferably zero, if b is equal to 1.

5. The alloy as claimed in claim 4, wherein the polyaryl ether ketone has a structure containing the following repeating units: or or or !_ Ο·'

6. The alloy as claimed in claim 1 or 2 or 3, wherein the polyimide has the following repeating units: in which R 1 is (a) a substituted or unsubstituted aromatic radical of the following formulae or (/9) a divalent radical of the formula IE alkylidene each having 1 to 6 carbon atoms or cycloalkylene and cycloalkylidene each having 4 to 8 carbon atoms; R 2 is an aromatic hydrocarbon carbon radical having 6 to 20, preferably 6 to 12, carbon atoms or halogen or a halogen- or alkyl-substituted derivative thereof, the alkyl group containing 1 to 6 carbon atoms, an alkylene or cycloalkylene radical having 2 to 20 carbon atoms or a divalent radical of the formula 3 ) 0 -4 3 >o-4 in which R 3 and R* are as defined above and R* may also be a direct bond.

7. The alloy as claimed in one or more of claims 1 to 5, wherein the polyimide contains repeating units of the following formula: II / C \ -0-Z N II _p20 II C / \ N Z· II -0-R 1 ~ in which R 1 and R 2 are as defined above, ( r 5 : -o-zrepresenting o-o in which R 5 , independently of one another, is hydrogen, alkyl or alkoxy, each having 1 to 6 carbon atoms in the alkyl radical, or is in which the oxygen is linked with one of the rings and is in the ortho- or para-position relative to one of the bonds of the imide carbonyl group.

8. The alloy as claimed in one or more of claims 1 to 6, wherein the polyimide has repeating units of the following formula:

9. The alloy as claimed in one or more of claims 1 to 9, wherein the polyaryl ester c) is a polyester carbonate based on a dihydroxyphenol, a carbonate precursor and an aromatic dicarboxylic acid or a reactive derivative thereof, or is derived from at least one dihydroxyphenol and at least one aromatic dicarboxylic acid.

10. The alloy as claimed in claim 9, wherein the dihydroxyphenol has the following formula: HO (Y ), OH in which Y' is alkyl having 1 to 4 carbon atoms, cycloalkyl having 6 to 12 carbon atoms or halogen, m', - 28 independently of one another, is zero, 1, 2, 3 or 4 and R' is alkylene or alkylidene each having 1 to 8 carbon atoms or an arylene radical having 6 to 20 carbon atoms, m’ preferably-being zero and R’ preferably being alkylidene havinq 3 Carbon atoms.

11. The alloy as claimed in claim 10, wherein the dihydroxyphenol is bisphenol A.

12. The alloy as claimed in claim 9, wherein the aromatic dicarboxylic acid has the following formula: HOOC - R” - COOH in which R is selected from the groups in which f is zero or 1 and W represents 0, S0 2 , CO, C(CH 3 ) 2 , CH 2 , S or ( T)o-4 < T )0 - 4 in which W' has the meaning given above for W, T in the formulae is alkyl having 1 to 6 carbon atoms, preferably methyl, propyl or butyl, or halogen, preferably F, Cl or Br.

13. The alloy as claimed in claim 12, wherein the aromatic dicarboxylic acid is selected from isophthalic acid, terephthalic acid and mixtures thereof; and in which the reactive derivatives of the acids are selected from terephthaloyl dichloride, isophthaloyl dichloride and mixtures thereof.

14. The alloy as claimed in claim 9, wherein the carbonate precursor is phosgene.

15. The alloy as claimed in one or more of claims 9 to 14, wherein the polyester carbonate is a copolymer of bisphenol A, terephthaloyl dichloride, isophthaloyl dichloride or mixtures of these two, and phosgene.

16. The alloy as claimed in one or more of claims 9 to 13, wherein the dihydroxyphenol is bisphenol A, and the aromatic dicarboxylic acids are terephthalic acid or isophthalic acid or mixtures of these two.

17. The alloy as claimed in claim 1, wherein the polyaryl ether ketone contains repeating units of the following formula and the polyimide contains repeating units of the following formula z N \ CH 3 - 30 and the polyaryl ester contains repeating units of the following formula

18. The alloy as claimed in claim 1, wherein the polyaryl ether ketone contains repeating units of the following formula and the polyimide contains repeating units of the following formula and the polyaryl ester contains repeating units of the following formula

19. The alloy as claimed in claim 1, wherein the polyaryl ether ketone contains repeating units of the following formula and the polyaryl ester contains repeating units of the following formula and the polyaryl ester contains repeating units of the following formula ch 3 CHg

20. The use of an alloy as claimed in one or more of claims 1 to 19 for the preparation of molded articles or as the matrix material for composites.

21. The use as claimed in claim 20, wherein carbon fibers or glass fibers are used for the composites.

22. The use as claimed in claim 20 for the preparation of injection molded products or extruded products in the form of fibers, films or tubes. - 32

23. An alloy of a homogeneously mixed polymer according to claim 1, substantially as hereinbefore described and exemplified.

24. Use according to claim 20, substantially as hereinbefore described.