DE19756141A1 - Radiopaque thermoplastic molding compound - Google Patents

Abstract

Thermoplastic moulding compound containing (A) one or several vinyl polymers, (B) BaSO4 particles, and (C) optionally a bifunctional reactive compound polycondensate. The BaSO4 particles have an average diameter of more than 100 nm and a maximum average diameter of 3 000 nm. Also described is the use of the inventive moulding compound in the production of toys or medical items, in addition to moulded parts made from said moulding compound.

Description

The invention relates to a thermoplastic molding composition, and in particular one X-ray opaque, thermoplastic molding compound with excellent notched impact strength.

The detection of plastic parts in the human body, e.g. B. swallowed Plastic toys or plastic particles injected into the tissue by accidents and medical technology articles is becoming increasingly important.

One detection method for foreign bodies in the human organism is X-ray diagnostics. Conventional plastics mostly exist from elements with a low atomic number (OZ) such as carbon (OZ = 6), Hydrogen (OZ = 1), oxygen (OZ = 8) and nitrogen (OZ = 7). The effective ones The atomic numbers of the plastics thus resemble those of the water, so that the X-ray densities of conventional plastics and water are comparable. Therefore, many conventional plastics in living tissue are largely X-rayed radiation transparent.

To increase the x-ray density, elements with a higher atomic number can be used in the Serve plastics, e.g. B. chlorine (OZ = 17) in polyvinyl chloride, silicon (OZ = 14) in Silicones and fluorine (OZ = 9) in polyfluorocarbon. Of the usual plastics only polyvinyl chloride has one for its high chlorine concentration X-ray diagnostics sufficient contrast on (Progr. Röntgenstrasse 128, 6 (1978) 758 to 762).

Another possibility for increasing the X-ray density of plastics is the use of fillers such as glass fibers (SiO ₂ ) or dyes or pigments, which consist of elements with a higher atomic number, e.g. B. TiO ₂ (Ti: OZ = 22).

In medicine, X-ray diagnostics uses compounds that contain atoms with a high atomic number (X-ray contrast agents) such as BaSO ₄ (Ba: OZ = 56) or organic iodine compounds (iodine: OZ = 53) to make the body's own structures visible.

In order to effectively X-ray different plastics, especially those without elements with a higher atomic number (OZ <8), one can e.g. B. subsequently incorporate BaSO ₄ . The above-mentioned organic iodine compounds are generally not suitable for incorporation into plastics, since the high processing temperatures during the molding of the plastic parts can decompose these compounds.

If BaSO _{4 is incorporated} into polymers, the X-ray contrast is expected to be significantly improved compared to the unfilled polymer. However, conventional fillers can significantly influence the mechanical properties of the polymers obtained.

The present invention is therefore based on the object of thermoplastic To provide molding compounds which not only show good X-ray contrast, but also have excellent mechanical properties.

This object is achieved by the provision of thermoplastic molding compositions containing

• (A) one or more vinyl polymers
• (B) BaSO ₄ particles and
• (C) optionally a polycondensate of bifunctional reactive compounds,

which are characterized in that the BaSO ₄

-Particle (B) a medium particle have a size of more than 100 nm and at most 3000 nm.

The BaSO ₄ particles preferably have an average particle size between 150 and 2000 nm, particularly preferably between 300 and 1000 nm.

Surprisingly, the molding compositions according to the invention have a particularly fine color Constant combination of properties, namely excellent impact strength and high rigidity (modulus of elasticity).

Suitable vinyl polymers (A) are homopolymers or copolymers of one or more vinyl group-containing ethylenically unsaturated monomers. Suitable monomers are vinyl acetate, styrene, α-methylstyrene, nucleus-substituted styrenes, acrylonitrile, methacrylonitrile, methyl methacrylate, maleic anhydride, N-substituted Maleimides, chloroprene, 1,3-butadiene, C ₁ -C ₁₈ alkyl acrylates and methacrylates. In particular, the following are possible:

• (A1) rubber-free vinyl polymers,
• (A2) rubber-containing vinyl polymers, e.g. B. graft polymers of Vinyl monomers on a rubber or
• (A3) mixtures of (A1) and (A2).

According to the invention, graft polymers (A2) are preferably those in which one Rubber (a) styrene or (b) methyl methacrylate or (c) a mixture of (i) Styrene, α-methylstyrene, nucleus-substituted styrene, methyl methacrylate or one Mixture thereof and (ii) acrylonitrile, methacrylonitrile, maleic anhydride, N-substi tuated maleimides or a mixture thereof are graft-polymerized. In the case 95 to 50% by weight of (c) and 5 to 50% by weight (ii) of (c) are preferably used. Suitable rubbers are all rubbers with glass transition temperatures ≦ 10 ° C, preferably those which contain copolymerized butadiene. Examples are polybu tadiene, styrene-butadiene copolymers, acrylonitrile-butadiene copolymers, acrylic latex rubbers, optionally with built-in structure derived from butadiene tur units, acrylate rubbers, which are a cross-linked rubber such as polybutadiene or a copolymer of butadiene with an ethylenically unsaturated monomer such as styrene and / or acrylonitrile as the core. Polybutadiene is as rubber prefers.  

The graft (co) polymers (A2) preferably contain 10 to 95% by weight, in particular 20 to 70% by weight of rubber and 90 to 5% by weight, in particular 80 to 30% by weight of graft (co) polymerized Monomers. The rubbers are in these graft (co) polymers in the form of at least partially crosslinked particles having an average particle diameter (d ₅₀ ) of 0.05 to 20 μm, preferably 0.1 to 2 μm and particularly preferably 0.1 to 0 , 8 µm before (determined by ultracentrifugation, see W. Scholtan, H. Lange, Kolloid, Z. and Z. Polymer 250 (1972), pages 782 to 796).

The rubber-containing vinyl polymers (A2) include, for. B. graft copolymers with rubber-elastic properties, which are essentially obtainable from at least two of the following monomers: chloroprene, 1,3-butadiene, isoprene, styrene, acrylonitrile, ethylene, propylene, vinyl acetate, C ₁ -C ₁₈ -alkyl acrylates and methacrylates. Such polymers are e.g. B. in "Methods of Organic Chemistry" (Houben-Weyl), Vol. 14/1, Georg Thieme Verlag, Stuttgart, 1962, pp. 393-406 and in CB Bucknall, "Toughened Plastics", Appl. Science Publishers, London 1977. Preferred polymers (A2) are partially crosslinked and have gel contents of over 20% by weight, preferably over 40% by weight, in particular over 60% by weight.

Preferred rubbery vinyl polymers (A2) are graft polymers of:

• (A2.1) 5 to 95, preferably 30 to 80 parts by weight of a mixture of
• (A2.1.1) 50 to 95 parts by weight of styrene, α-methylstyrene, halogen or methyl-core-substituted styrenes, methyl methacrylate or Mixtures of these compounds and
• (A.2.1.2) 5 to 50 parts by weight of acrylonitrile, methacrylonitrile, methyl methacrylate, maleic anhydride, C ₁ -C ₄ -alkyl- or phenyl-N-substituted maleimides or mixtures of these monomers
• (A2.2) 5 to 95, preferably 20 to 70 parts by weight of rubber poly merisat with a glass transition temperature below -10 ° C.

Preferred graft polymers (A2) are e.g. B. with styrene and / or acrylonitrile and / or alkyl acrylates or methacrylates grafted polybutadienes, butadiene / -sty roll copolymers and acrylic rubbers; d. H. Copolymers of DE-OS 16 94 173 (= U.S. Patent 3,564,077); with acrylic or methacrylic acid alkyl esters, vinyl acetate, acrylonitrile, styrene and / or alkylstyrenes Butadienes, butadiene / styrene or butadiene / acrylonitrile copolymers, polyisobutenes or polyisoprene, as described in DE-OS 23 48 377 (= US Pat. No. 3,919,353) are.

Particularly preferred polymers (A2) are ABS polymers, such as those used for. B. in the DE-OS 20 35 390 (= US-PS 3 644 574) and in DE-OS 22 48 242 (= GB-PS 1 409 275) are described.

Particularly preferred graft polymers (A2) can be obtained by graft polymerization of

• a) 10 to 70, preferably 15 to 50, in particular 20 to 40 wt .-%, based on the graft polymer (A2), of acrylic acid esters or methacrylic acid esters or from 10 to 70, preferably 15 to 50, in particular 20 to 40 % By weight of a mixture of 10 to 50, preferably 20 to 35% by weight, based on the mixture, acrylonitrile, acrylic acid ester or methacrylic acid esters and 50 to 90, preferably 65 to 80 wt .-%, based on the Mixture, styrene (as graft (A2.1)
• b) 30 to 90, preferably 50 to 85, in particular 60 to 80% by weight on graft polymer (A2), a butadiene polymer with at least 50 % By weight, based on b), butadiene residues (as graft base (A2.2),

wherein preferably the gel fraction of the graft base b) is at least 40% by weight (measured in toluene), the degree of graft G 0.15 to 0.55 and the mean particle diameter d ₅₀

the graft polymer (A2) 0.05 to 2 microns, preferably 0.1 to 0.6 microns is.

The degree of grafting G is the weight ratio of grafted monomers to Graft base (dimensionless number).

Acrylic acid esters or methacrylic acid esters a) are esters of acrylic acid or meth acrylic acid and monohydric alcohols with 1 to 18 carbon atoms. Particularly preferred are methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl acrylate, t-butyl acrylate and t-butyl methacrylate.

The butadiene polymer b) may in addition to butadiene up to 50 wt .-%, based on b), of residues of other ethylenically unsaturated monomers such as styrene, acrylonitrile, C ₁ -C ₄ alkyl esters or acrylic or methacrylic acid (such as methyl acrylate, ethyl acrylate, methyl methacrylate , Ethyl methacrylate), vinyl ester and / or vinyl ether. Polybutadiene is preferred.

Preferred vinyl polymers (A1) are copolymers of styrene on the one hand, α-methylstyrene, nucleus-substituted styrene or mixtures (A1.1) and on the other hand Acrylonitrile, methacrylonitrile, methyl methacrylate, maleic anhydride, N-substituted maleimide or mixtures thereof (A1.2). These preferably contain copoly merisate 50 to 98 wt .-% (A1.1) and 50 to 2 wt .-% (A1.2).

Particularly preferred copolymers (A1) are those of (i) styrene, acrylonitrile and optionally methyl methacrylate, (ii) from α-methylstyrene, acrylonitrile and given if methyl methacrylate and (iii) styrene, α-methylstyrene, acrylonitrile and the like otherwise methyl methacrylate.

The best known are styrene-acrylonitrile copolymers, which are formed by radical poly merization, in particular by emulsion, suspension, solution or bulk poly merization can be produced.  

The copolymers (A1) preferably have molecular weights M _w (weight average, determined by light scattering or sedimentation) from 15,000 to 200,000.

Other particularly preferred copolymers (A1) are randomly structured Copolymers of styrene and maleic anhydride, the z. B. by a continuous Orier bulk or solution polymerization with incomplete sales from the corresponding monomers can be prepared. Your composition can can be varied within wide limits. They preferably contain 5 to 25% by weight Maleic anhydride units.

Instead of styrene, these polymers can also contain nucleus-substituted styrenes, such as p-methylstyrene, vinyltoluene, 2,4-dimethylstyrene and other substituted styrenes, such as α-methylstyrene.

The thermoplastic copolymers (A1) used according to the invention can from those used to prepare the graft copolymers (A2) Rubber graft-polymerized monomers or similar monomers obtained are, in particular from styrene, α-methylstyrene, halostyrene, acrylonitrile, meth acrylonitrile, methyl methacrylate, maleic anhydride, vinyl acetate, N-substituted Maleimides or mixtures thereof. Copolymers of 98 to 50 are preferred % By weight of styrene, α-methylstyrene, methyl methacrylate or mixtures thereof with 2 to 50% by weight of acrylonitrile, methacrylonitrile, methyl methacrylate, maleic anhydride or Mixtures of these.

Such copolymers (A1) are also formed in the graft copolymerization speaking monomer as by-products because the graft polymerization is not full is constant. It is common, in addition to the copoly contained in the graft polymer (A2) to mix in separately prepared copolymers (A1). These don't have to with the ungrafted resin components present in the graft polymer (A2) be chemically identical.  

Particularly preferred thermoplastic copolymers (A1) contain 20 to 40 % By weight of acrylonitrile and 80 to 60% by weight of styrene or α-methylstyrene siert. These copolymers are known. They preferably have molecular weight weights from 15000 to 200000.

Any mixtures of poly can also be used as vinyl polymer (A) merisate (A1) and (A2).

The polycondensates (C) of bifunctional reactive compounds are preferred Polycarbonates and / or polyester.

Preferred polycarbonates are those based on the diphenols of the formula (I)

wherein
A is a single bond, a C ₁ -C ₅ alkylene, a C ₂ -C ₅ alkylidene, a C ₅ -C ₆ cycloalkylidene, -O-, -SO-, -CO-, -S-, -SO ₂ - represents a C ₆ -C ₁₂ arylene residue which is condensed with further aromatic rings which may contain heteroatoms,
B is chlorine or bromine
x 0, 1 or 2 and
p is 1 or 0,
and / or alkyl-substituted dihydroxydiphenylcycloalkanes of the formula (II)

wherein
R ¹ and R ² independently of one another are hydrogen, halogen, preferably chlorine or bromine, C ₁ -C ₈ alkyl, C ₅ -C ₆ cycloalkyl, C ₆ -C ₁₀ aryl, preferably phenyl and C ₇ -C ₁₂ aralkyl , preferably phenyl-C ₁ -C ₄ -alkyl, in particular benzyl,
m is an integer from 4 to 7, preferably 4 or 5,
R ³ and R ^{4 can be} selected individually for each Z, independently of one another hydrogen or C ₁ -C ₆ alkyl and
Z means carbon, with the proviso that on at least one atom ZR ³ and R ⁴ simultaneously mean alkyl, preferably methyl.

Polycarbonates suitable according to the invention are both homopolycarbonates and Copolycarbonates.

The polycondensate (C) can also be a mixture of the thermo defined above plastic polycarbonates.

Polycarbonates can be made in a known manner from diphenols with phosgene Phase boundary process or with phosgene according to the process in homogeneous Phase, the so-called pyridine process, the molecular  weight in a known manner by a corresponding amount of known chains cancel can be set.

Suitable chain terminators are e.g. B. phenol, p-chlorophenol, p-tert-butylphenol or 2,4,6-tribromophenol, but also long-chain alkylphenols, such as 4- (1,3-tetramethyl butyl) phenol according to DE-OS 28 42 005 or monoalkylphenol or dialkylphenol with total of 8 to 20 carbon atoms in the alkyl substituents according to DE-A-35 06 472.2 such as 3,5-di-tert-butylphenol, p-iso-octylphenol, p-tert-octylphenol, p-dodecylphenol and 2- (3,5-dimethylheptyl) phenol and 4- (3,5-dimethylheptyl) phenol.

The amount of chain terminators is generally between 0.5 and 10 mol% based on the molar mass of the diphenols (I) used in each case.

The polycarbonates (C) used according to the invention have average molecular weights (M _w , weight average, measured, for example, by ultracentrifugation or scattered light measurement) from 10,000 to 200,000, preferably from 20,000 to 80,000.

Suitable diphenols of formula (I) are e.g. B. hydroquinone, resorcinol, 4,4'-dihy hydroxydiphenyl, 2,2-bis (4-hydroxyphenyl) propane, 2,4-bis (4-hydroxyphenyl) -2-meth ylbutane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 2,2-bis (3-chloro-4-hydroxy phenyl) propane, 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane.

Preferred diphenols of the formula (I) are 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (3,5-di chloro-4-hydroxyphenyl) propane and 1,1-bis (4-hydroxyphenyl) cyclohexane.

Preferred diphenols of the formula (11) are 1,1-bis (4-hydroxyphenyl) -3,3-dimethyl cyclohexane, 1,1-bis- (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane and 1,1-bis- (4-hy droxyphenyl) -2,4,4-trimethyl-cyclopentane.

The polycarbonates (C) used according to the invention can ver in a known manner be branched, preferably by incorporation of 0.05 to 2.0 mol%, based on the sum of the diphenols used, on three or more than three functional ones Connections, e.g. B. those with three or more than three phenolic groups.  

In addition to bisphenol A homopolycarbonate, preferred polycarbonates are the Co polycarbonates of bisphenol A with up to 15 mol%, based on the molar sum Diphenols, on 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane.

Aromatic polyesters can also be used as the polycondensate (C).

Preferred polyesters (C) are polyalkylene terephthalates. These are reaction pro products of aromatic dicarboxylic acids (or their reactive derivatives, e.g. dime ethyl esters or anhydrides) and aliphatic, cycloaliphatic or arylaliphati rule diols and mixtures of such reaction products.

Preferred polyalkylene terephthalates can be derived from terephthalic acid (or its reactive derivatives) and aliphatic or cycloaliphatic diols with 2 to 10 Produce carbon atoms using known methods (Kunststoff-Handbuch, volume VIII, page 695 ff., Carl Hanser Verlag, Munich 1973).

Preferred polyalkylene terephthalates contain 80 to 100, preferably 90 to 100 Mol%, based on the dicarboxylic acid component, terephthalic acid residues and 80 to 100, preferably 90 to 100 mol%, based on the diol component, of ethylene glycol and / or 1,4-butanediol residues. In addition to terephthalic acid esters, 0 to 20 mol% Residues of other aromatic dicarboxylic acids with 8 to 14 carbon atoms or alipha tic dicarboxylic acids containing 4 to 12 carbon atoms, such as residues of phthalic acid Isophthalic acid, naphthalene-2,6-dicarboxylic acid, 4,4'-diphenyldicarboxylic acid, Bern stone, adipic, sebacic, azelaic or cyclohexanediacetic acid. In addition to ethylene Glycol and / or 1,4-butanediol residues are 0 to 20 mol% of other aliphatic Diols with 3 to 12 carbon atoms or cycloaliphatic diols with 6 to 12 carbon atoms included, e.g. B. residues of 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, 3-methylpentanediol-1,3 and -1,6, 2-ethylhexanediol-1,3,2, 2-diethylpropanediol-1,3, Hexanediol-2,5, 1,4-di (β-hydroxyethoxyphenyl) propane, 2,4-dihydroxy-1,1,3,3-tetra methylcyclobutane, 2,2-bis (3-β-hydroxyethoxyphenyl) propane and 2,2-bis (4-hy droxypropoxyphenyl) propane (DE-OS 24 07 647, 24 07 776, 27 15 932).  

The polyalkylene terephthalates can be 3- or by incorporating relatively small amounts Tetravalent alcohols or 3- or 4-based carboxylic acids as described in DE-OS 19 00 270 and U.S. Patent 3,692,744.

Examples of preferred branching agents are trimesic acid, trimellitic acid, tri methylolethane and propane and pentaerythritol. It is advisable not to use more than 1 mole% of the branching agent, based on the acid component.

Polyalkylene terephthalates which consist solely of terephthalic acid are particularly preferred (or their reactive derivatives, e.g. their dialkyl esters) and ethanediol and / or 1,4-butanediol have been prepared, and mixtures thereof.

Preferred polyalkylene terephthalates are also copolyesters which consist of at least two of the above diols are prepared; are particularly preferred copolyesters Poly (ethylene glycol / 1,4-butanediol) terephthalates. In the copolyesters, the ver different diol residues in the form of blocks or statistically distributed.

The polyalkylene terephthalates generally have an intrinsic viscosity of 0.4 to 1.4 dl / g, preferably 0.5 to 1.3 dl / g, in particular 0.6 to 1.2 dl / g, each measured in phenol / o-dichlorobenzene (1: 1 parts by weight) at 25 ° C.

The BaSO ₄ particles (B) used according to the invention have an average particle diameter d ₅₀ of more than 100 nm, but at most 3000 nm. The mean particle diameter d ₅₀ is defined as the diameter above and below which 50% by weight of the particles lie. It can be determined by means of ultracentrifuge measurement (W. Scholtan, H. Lange, Kolloid. Z. and Z. Polymer 250 (1972), 782-796).

For example, the following commercially available commercial products can be used Sachtoperse HP, Blanc fixe N, XR-IIX (Sachtleben Chemie GmbH, Duisburg); Blanc fixe HD 80 (Solvay Barium Strontium GmbH, Hanover).  

The BaSO ₄ particles (B) preferably have an average particle diameter between 200 and 2000 nm, particularly preferably between 300 and 1000 nm.

In addition to the components according to the invention, the molding compositions can contain customary additives sets such as pigments, fillers, stabilizers, antistatic agents, lubricants, mold release agents medium, contain flame retardants, provided they do not have impact strength to reduce.

The BaSO ₄ particles (B) can be incorporated into the thermoplastic molding composition (A) and, if appropriate, the polycondensate (C), for example by direct kneading or extrusion of the plastics (A) and, if appropriate, (C) and the BaSO ₄ particles (B) and, if appropriate, the other auxiliaries. Preferably 0.1 to 50, particularly preferably 0.1 to 30 and very particularly preferably 0.1 to 10% by weight of BaSO _{4 are added} to the polymer (A), if appropriate as a mixture with the polycondensate (C) and at elevated levels Mixed temperatures, e.g. B. 100 ° C to 280 ° C in conventional mixing units, kneaders, internal mixers, roller mills, screw machines or extruders. The residence times in the mixing process can vary between 10 seconds and 30 minutes depending on the intensity of the mixing.

The molding compositions thus obtained are then in the usual way, for. B. by Injection molding further processed into molded parts, especially toys or medical technology articles such. B. catheters.

The following examples further illustrate the invention:

Examples

The thermoplastic molding compositions are produced by kneading the constituents ABS, SAN, BaSO ₄ and various customary additives (pigments, mold release agents, antistatic agents and lubricants) in a stamp kneader from Farelle at 170-185 ° C, a speed of 590 min ^-1 and a kneading time of 3-5 min. The molding compositions produced in this way are rolled (roller temperature 150 ° C.), granulated and injected into test specimens on an injection molding machine from Arburg with a locking force of 75 t at a melt temperature of 240 ° C., a mold temperature of 70 ° C. and an injection speed of 40 mm / s.

The test specimens produced in this way are tested in accordance with the following standards:

• 1. Melt index (volume flow index MVR) ISO 1133
• 2.Izod impact strength ISO 180 / 1A flat bar 80 × 10 × 4 mm ³
• 3. Zug-E module ISO 527 shoulder bar No. 3; 170 × 10 × 4 mm ³

The results of the test are shown in the following table.

The polymer composition of the polymers listed in the table is in each case identical and reads as follows:

SAN is a thermoplastic resin made of 28% by weight acrylonitrile and 72% by weight styrene. SAN can be made by emulsion polymerization (SAN latex) or bulk process. The viscosity of the SAN resin is characterized by the L value (L value = η _spec / c at c = 5 g / l in DMF at 25 ° C). The L value of the SAN resin used is 60.

ABS graft polymer in powder form is obtained by emulsion polymerization of Styrene and acrylonitrile in the presence of an aqueous polybutadiene emulsion (poly butadiene base). Styrene and acrylonitrile are applied to the polybuta grafted on dien particles. As is known, the grafting is not complete, so  that in addition to grafted SAN, there is also free SAN in the ABS graft powder. The ABS graft polymer consists of 55% by weight of polybutadiene and 45% by weight of SAN (Styrene: acrylonitrile = 72% by weight: 28% by weight). The particle size of the polybutadiene basis is 0.4 µm.

table

Claims (13)

1. Thermoplastic molding composition containing

• (A) one or more vinyl polymers,
• (B) BaSO ₄ particles and
• (C) optionally a polycondensate of bifunctional reactive compounds,

characterized in that the BaSO ₄ particles have an average particle diameter of more than 100 nm and at most 3000 nm. 2. Molding composition according to claim 1, characterized in that the BaSO ₄ particles have an average particle diameter between 200 and 2000 nm. 3. Molding composition according to claim 1 or 2, characterized in that the vinyl polymer (A) is selected from

• (A1) rubber-free vinyl polymers
• (A2) rubber-containing vinyl polymers
• (A3) mixtures of (A1) and (A2).

4. Molding composition according to one of claims 1 to 3, characterized in that the rubber-free vinyl polymers (A1) are selected from copoly merisaten

• (A1.1) styrene, α-methylstyrene, nucleus-substituted styrene or mixtures thereof and
• (A1.2) acrylonitrile, methacrylonitrile, methyl methacrylate, maleic anhydride, N-substituted maleimide or mixtures thereof.

5. Molding composition according to claim 4, characterized in that the copolymer (A1) contains 50 to 98% by weight (A1.1) and 50 to 2% by weight (A1.2). 6. Molding composition according to one of claims 1 to 5, characterized in that the copolymer (A1) is a copolymer of (i) styrene, acrylonitrile and optionally methyl methacrylate, (ii) α-methylstyrene, acrylonitrile and optionally methyl methacrylate or (iii) styrene, α-methylstyrene, acrylonitrile and is optionally methyl methacrylate. 7. Molding composition according to one or more of claims 1 to 6, characterized in that the rubber-containing vinyl polymers (A2) graft polymers

• (A2.1) 5 to 95, preferably 30 to 80 parts by weight of a mixture of
• (A2.1.1) 50 to 95 parts by weight of styrene, α-methylstyrene, halogen- or methyl-core-substituted styrenes, methyl methacrylate or mixtures of these compounds and
• (A2.1.2) 5 to 50 parts by weight of acrylonitrile, methacrylonitrile, methyl methacrylate, maleic anhydride, C ₁ -C ₄ -alkyl- or phenyl-N-substituted maleimides or mixtures of these compounds
• (A2.2) 5 to 95, preferably 20 to 70 parts by weight of rubber polymer with a glass transition temperature below -10 ° C

are. 8. Molding composition according to one of claims 1 to 7, characterized in that the graft polymer (A2) is obtained by graft polymerization of

• a) 10 to 70, based on the graft polymer (A2), of acrylic esters or methacrylic acid esters or from 10 to 70, preferably 15 to 50, in particular 20 to 40% by weight of a mixture of 10 to 50, preferably 20 to 35% by weight .-%, based on the mixture, acrylonitrile, acrylic acid ester or methacrylic acid ester and 50 to 90, preferably 65 to 80% by weight, based on the mixture, of styrene (as graft (A2.1))
• b) 30 to 90, preferably 50 to 85, in particular 60 to 80% by weight, based on the graft polymer (A2), of a butadiene polymer with at least 50% by weight, based on b), butadiene residues (as the graft base (A2 .2)).

9. Molding composition according to one of claims 1 to 7, characterized in that the polycondensate (C) is a polycarbonate or polyester. 10. Use of a molding composition according to one of claims 1 to 10 for Manufacture of molded parts. 11. Use according to claim 10 for the manufacture of toys or medical articles. 12. Molded parts, produced according to one of claims 1 to 9. 13. Toys and medical technology articles according to claim 12.