MXPA01006087A - Thermoplastic moulding materials - Google Patents

Abstract

The invention relates to thermoplastic moulding materials and the use thereof in the production of films, shaped bodies and fibres, containing (A) 5-98 wt.%, in relation to the overall weight of the moulding materials, of at least one rubberlike graft co-polymer, (B) 1-90 wt.%, in relation to the overall weight of the moulded material, of at least one other copolymer, and (C) 1-70 wt.%, in relation to (A), (B), (C) and optionally (D), of one rubber-elastic block copolymer made from at least one block CA forming a hard phase and comprising polymerized units consisting of vinylaromatic monomers, in addition to an elastomer block CB/A forming a soft phase and containing a diene, and (D) 0-300 wt.%, in relation to the weight of constituents (A) (C), of a polycarbonate, (D) 0-30 wt.%, in relation to the overall weight of the moulding materials, of usual additives and auxiliary processing agents.

Description

COMPOSITIONS FOR THERMOPLASTIC MOLDING The present invention relates to compositions for thermoplastic molding with better processing properties, based on graft copolymers and block copolymers. Mixtures of impact-modified thermoplastic copolymers based on vinylaromatic polymers and grafted rubbers are known to skilled workers as ABS polymers or polymers ASA, and are commercially available, the combinations of these ASA polymers or ABS polymers with other thermoplastics, in particular with polycarbonates, are also known.The introduction of even faster processing machinery means that the products are required of this type have, in particular, high creep during the injection molding and ability to release without breaking In the thermoforming an important factor is the high elongation to the break In order to optimize these properties, different additives are generally used, but these they tend to improve only one property while adversely affecting another desired property.For example, additives to improve creep and thermoforming properties often cause loss of mechanical properties, while additives to improve molding ability often deteriorate the Therefore, an objective of the present i The invention is to provide compositions for thermoplastic molding based on ABS polymers or ASA polymers and having a balanced property profile. We have found that this objective is achieved, in a first embodiment of the invention, by means of thermoplastic molding compositions containing: (A) from 5 to 98% by weight, based on the total weight of the molding composition, of an elastomeric graft copolymer consisting of: (ai) from 30 to 90% by weight, based on (A), of a grafted base with a glass transition temperature (Tg) below -10 ° C, prepared from of: (au) an at least partially crosslinked acrylate polymer formed of: (am) from 50 to 99.9% by weight, based on (au) of at least one C? -C? alkyl alkyl acrylate. (an2) from 0.1 to 5% by weight, based on (an), of at least one polyfunctional crosslinking monomer, and (an3) from 0 to 49.9% by weight, based on (an), of another monomer that is copolymerizable with (am) selected from the group consisting of vinylalkyl (of Ci-Cß) ethers, butadiene, isoprene, styrene, acrylonitrile and methacrylonitrile, and / or methyl methacrylate and / or (a? 2) a diene polymer consisting of: (a? 2?) from 60 to 100% by weight, based on (a? 2), of at least one diene, and (a? 22) from 0 to 40% by weight, based on (a? 2) ) of other copolymerizable monomers selected from the group consisting of C?-C? alkyl acrylates, vinylalkyl (Ci-Cβ) ethers, butadiene, isoprene, styrene, acrylonitrile and methacrylonitrile, and / or methyl methacrylate. (a2) from 10 to 70% by weight, based on (A), of a graft with a (Tg) above 50 ° C, grafted on the base for grafting and consisting of: (a2?) from 50 to 95% by weight based on (a2), of at least one vinylaromatic monomer (a22) from 5 to 50% by weight, based on (a2), of at least one polar comonomer, copolymerizable, selected from the group consisting of : acrylonitrile, methacrylonitrile (meth) acrylates of C1-C4 alkyl, maleic anhydride and maleimides, and (meth) acrylamide and / or vinylalkyl (of C? ~ C8) ethers, or a mixture of these (B) from 1 to 90 % by weight, based on the total weight of the molding composition, of a copolymer composed of: (bi) from 50 to 99% by weight, based on (B), of at least one vinylaromatic monomer. and (b2) from 1 to 50% by weight, based on (B), of monomers as described for (a22), (C) from 1 to 70% by weight, based on (A), (B) , (C) and, as appropriate, (D) and (E), of an elastomeric block copolymer composed of: at least one CA block forming a hard phase and having copolymerized units of a vinylaromatic monomer, and at least one elastomeric block C (B / AJ forming a soft phase and having copolymerized units of a vinylaromatic monomer, and also of a diene where the vitreous transition temperature (Tg) of the CA block is above 25 ° C and that of the C block (B / A> is below 25 ° C, and the selected phase-volume relationship of the block C to the block C (B / A) is such that the proportion of the phase lasts in all the block copolymer is from 1 to 40% by volume and the proportion by weight of the diene throughout the block copolymer is less than 50% by weight where the ratio of the 1, 2 bonds in the polydiene, based on the total of the 1,2- and 1,4- cis / trans bonds is below 15% and (D) from 0 to 300% by weight , based on the weight of the components (A) to (C) of a polycarbonate. (E) from 0 to 30% by weight, based on the total weight of the composition for molding, of the traditional additives and processing aids. The thermoplastic molding compositions of the invention have better creep than comparable molding compositions together with better demolding and thermoformability and show no reduction in coating capacity and are largely free of constituents that vaporize or exude. These are suitable for producing films, castings (especially sheets) and fibers, with excellent post-processing capability for thermoforming, and also for producing injection-molded parts, especially for fast processing with short cycle times. If (A) is butadiene rubber they have excellent puncture resistance and impact resistance in the specimen with markedly improved notch. If (A) is an acrylate rubber, very good resistance shocks is a particularly noticeable feature. Multiple demanding applications require good processing capacity, high creep, good demolding capacity and good resistance to shocks of the finished part with respect to the fracture initiated or not started, together with good resistance to multiaxial shocks (implies that the resistance to shocks of the molded part is good in all directions, without directional preference), without substantial deterioration of other properties, such as thermal resistance, rigidity and resistance to bending. To improve creep it is normal to add lubricants, often with a reduction in rubber content. Products with low rubber content flow better than products of the same type with high rubber content, which have good impact resistance but poor fluidity. The simultaneous improvement in crash and creep resistance can not be obtained simply by changing the rubber content. Another objective of the present invention is therefore to provide compositions for thermoplastic molding based on ABS polymers or ASA polymers, in particular on ABS polymers, with better creep and impact resistance compared to those containing traditional materials and also with better unmold, along with paler intrinsic color. We have found that this objective is achieved by another embodiment of the present invention. This embodiment provides compositions for thermoplastic molding containing: (A) from 5 to 98.9% by weight, based on the total weight of the composition for molding, of a graft copolymer, elastomer consisting of: (ai) from 30 to 90% by weight, based on (A), of a graft base with a glass transition temperature (Tg) below -10 ° C, prepared from: (an) an at least partially crosslinked acrylate polymer formed from: (a) from 50 to 99.9% by weight, based on (an) from at least one Ci-Cio alkyl acrylate (an2) from 0.1 to 5% by weight, based on (an), from at least one polyfunctional crosslinking monomer, and (an3) from 0 to 49.9% by weight, based on (an) from at least one other monomer that is copolymerizable with (am) selected from the group consisting of vinylalkyl (Ci) - C8) ethers, butadiene, isoprene, styrene, acrylonitrile and methacrylonitrile, and / or methyl methacrylate and / or (a? 2) a diene polymer consisting of: (ai2?) From 60 to 100% by weight, based on (a? 2), of at least one diene, and (a? 22) from 0 to 40% by weight, based on (ai2) of other copolymerizable monomers selected from the group consisting of Ci-Cio alkyl acrylates , alkyl (C-Ce) vinyl esters, butadiene, isoprene, styrene, acrylonitrile and methacrylonitrile, and / or methyl methacrylate (a2) from 10 to 70% by weight, based on (A), of a graft with a glass transition temperature (Tg) above 50 ° C, grafted on the base for grafting and consisting of: (a2?) from 65 to 95% e n Weight, based on (a2), of at least one vinylaromatic monomer. (a22) from 5 to 35% by weight, based on (a2), of at least one polar, copolymerizable comonomer, selected from the group consisting of: acrylonitrile, methacrylonitrile, C? -C4 alkyl (meth) acrylates, maleic anhydride and maleimides, and (meth) acrylamide, and / or vinylalkyl (of C? -C8) ethers, or a mixture of these (B) from 1 to 90% by weight, based on the total weight of the composition for molding, of a copolymer composed of: (bi) from 69 to 81% by weight, based on (B), of at least one vinylaromatic monomer, and (b2) from 19 to 31% by weight, based on (B) ), of the monomers as described for (a22) (C) from 1 to 70% by weight, based on (A), (B), (C) and, as appropriate, (D) and (E) , of an elastomeric block copolymer composed of: at least one C n block forming a hard phase and having copolymerized units of a vinylaromatic monomer, and at least one elastomeric block C (B / A) forming a soft phase and having copolymerized units of a vinylaromatic monomer, and also of a diene where the vitreous transition temperature (Tg) of the CA block is above 25 ° C and that of the C block (B / A) is below 25 ° C, and the selected phase-volume relationship of the CA block to the C block (B / A) is such that the proportion of the hard phase in the complete block copolymer is from 1 to 40% by volume, and the weight ratio of the diene throughout the block copolymer is less than 50% by weight where the ratio of the 1,2-links in the polydiene, based on the total of the cis / trans 1,2- and 1,4- bonds is below 15% and (D) from 0 to 300% by weight , based on the weight of the components (A) to (C) of a polycarbonate, of the copolymers S-MA (styrene-maleic anhydride copolymers), of the copolymers S-imide-MA (styrene-imide-maleic anhydride copolymers) ), of the copolymers S-imide-AN-MA (styrene-imide-acrylonitrile-maleic anhydride copolymers), of a polymethacrylamide, or of a polymethacrylate, and (E) from 0 to 30% by weight, based on the weight total of the composition for molding, of additives and traditional processing aids.

In this embodiment, the use of a diene polymer (a? 2) as the graft base (ai) is preferred. The use of the butadiene polymer is particularly preferred, and it is very particularly preferable that a butadiene polymer be used and that the proportion of component C be from 0.1 to 15% by weight, based on (A), (B), (C) and, as appropriate, (D) and (E). The creep and impact resistance of the molding compositions of the invention, in particular, those based on ABS, ie, those in which a diene polymer (a? 2) is used as the base of the graft (ai) they can be significantly improved even with small amounts of component (C). This is particularly the case if the content of the component (b2) in the copolymer (B) used is in the range from 19 to 31% by weight, based on the component (B). In addition to the best flow and resistance to shocks with respect to the fracture initiated and the non-initiated, even at small proportions of component C, good demolding capacity is achieved with a very pale intrinsic color. With extrusion to obtain sheets, the molding compositions of this embodiment of the invention have a substantial improvement in impact strength perpendicular to the extrusion direction as a result of the addition of component (C). The compositions for molding this embodiment of the invention are, therefore, particularly suitable for producing molded parts, sheets, profiles, tubes and fibers, which can give excellent results in subsequent processing via thermoforming, and also to produce injection molded parts. , in particular where there is rapid processing with short cycle times and where high requirements are placed on the mechanical properties of the finished part. In the first embodiment, the component (A) of the molding compositions of the invention contains from 5 to 98% by weight, preferably from 10 to 90% by weight, and in particular from 15 to 80 by weight, based on the total weight of the compositions for molding, of an elastomeric graft copolymer. In the second embodiment, the component (A) of the molding compositions of the invention contains from 5 to 98.9% by weight, preferably from 5 to 98% by weight, and in particular from 10 to 90% by weight, and very particularly preferably from 15 to 80% by weight, based on the total weight of the compositions for molding, of at least one elastomeric graft copolymer.

This grafted copolymer (A) has been constituted from a graft base (ai) with a glass transition temperature Tg below -10 ° C and a graft (a2) with a glass transition temperature Tg above 50 ° C, the quantitative proportion of the graft base (au) + (a? 2) being from 30 to 90% by weight, preferably from 35 to 85% by weight, and in particular from 40 to 80% by weight, and the graft (a2) constituted in correspondence from 10 to 70% by weight, preferably from 15 to 65% by weight, and in particular from 20 to 60% by weight. The structure of the graft copolymer (A) is described in more detail below. The base of the graft (ai) has been constituted by: (an) an acrylate polymer at least partially crosslinked, formed of: (ain) from 50 to 99.9% by weight based on (au), at least one alkyl acrylate from Ci-Cio (a) from 0.1 to 5% by weight, based on (an), of at least one polyfunctional crosslinking monomer, and (an3) from 0 to 49.9% by weight, based on (an), of at least one other monomer which is copolymerizable with (am) selected from the group consisting of the vinylalkyl (of Ci- Ca) ethers, butadiene, isoprene, styrene, acrylonitrile and methacrylonitrile, and / or methyl methacrylate and / or (ai2) a diene polymer consisting of : (a? 2?) from 60 to 100% by weight, based on (ai2), of one or more dienes and (ai22) from 0 to 40% by weight, based on (a? 2), of others copolymerizable monomers selected from the group consisting of the vinylalkyl (of C?-C8) ethers, alkyl acrylates of Ci-Cι, isoprene, styrene, acrylonitrile and methacrylonitrile, and / or methyl methacrylate. The molding compositions that can be used are therefore those in which the graft base present in the component (A) is an acrylate polymer (an) alone or a butadiene polymer (a? 2) alone or a mixture of two polymers (an) and (a? 2). In cases where elaborate mixtures of the polymers (au) and (ai2) are used, the mixing ratio is not crucial, but is generally in the range from 4: 1 to 1: 4, in particular from 1: 2 to 2: 1. Preference is given to those compositions for thermoplastic molding in which a graft copolymer with a graft base (ai 2) (diene polymer, in particular butadiene polymer) is used as component (A). The acrylate polymers (au) have been formed from: (a) from 50 to 99.9% by weight, preferably from 55 to 98% by weight, and in particular from 60 to 90% by weight, based on (a) ), of at least one alkyl acrylate of Cyclo. Preferred acrylates are C 2 -C 0 alkyl acrylates, in particular ethyl acrylate, tertbutyl acrylate, isobutyl acrylate, n-butyl acrylate and 2-ethylhexyl acrylate, the latter two being particularly preferred (am) from 0.1 to 5% by weight, preferably from 0.25 to 4% by weight, and in particular from 0.5 to 3% by weight, based on (an), of crosslinking monomers, for example, polyfunctional monomers having at least two unconjugated olefinic double bonds, examples which must specifically be mentioned are ethylene glycol diacrylate, butanediol diacrylate, hexanediol diacrylate, ethylene glycol dimethacrylate, butanediol dimethacrylate, hexanediol dimethacrylate, divinyl benzene, diallyl maleate, diallyl fumarate, diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, tricyclodecenyl acrylate, dihydrodicyclopentadienyl acrylate, triallyl phosphate, allyl acrylate, m allyl ethacrylate and dicyclopentadienyl acrylate (DCPA) (see DE-C 12 60 135). (n3) from 0 to 49.9% by weight, preferably from 5 to 44.9% by weight, and in particular from 10 to 39.9% by weight, cori base in (au), of copolymerizable monomers with (am) selected from the group it consists of vinylalkyl (of C? ~ C8) ethers, (for example, vinyl methyl ether, vinyl propyl ether, vinyl ethyl ether), butadiene, isoprene, styrene, acrylonitrile and methacrylonitrile, and / or methyl methacrylate. The use of the comonomers of this type can control the profile of the properties of the polymers (u), for example, with respect to the degree of crosslinking, and in many cases this may be desirable. The processes for the preparation of the polymers (an) are known to the experts and are described in the literature. Products of this type are also available commercially. A preparation process which has proved particularly advantageous in some cases is emulsion polymerization, as described in DE-C 12 60 135. In the preparation of the graft copolymer (A) by the method described in DE-C 12 60 135 , first the base of the graft (ai) is prepared. If the base of the graft has to be an acrylate rubber, one or more acrylate (s) (am), a polyfunctional monomer (an2) and, if used, another copolymerized monomer (am) are polymerized in aqueous emulsion at a temperature of from 20 to 100 ° C, preferably from 50 to 80 ° C. Useful emulsifiers, such as the alkali metal salts of alkyl- and alkylaryl sulfonic acids, alkyl sulfates, fatty alcohol sulfonates, salts of higher fatty acids having from 10 to 30 carbon atoms, or resin soaps, can be used. . Preference is given to the sodium or potassium salts of the alkyl sulphonic acids or of the fatty acids having from 10 to 18 carbon atoms. It is convenient to use the emulsifiers in an amount from 0.5 to 5% by weight, in particular from 0.5 to 2% by weight, based on the total weight of the monomers that are used for the preparation of the graft base (ai). Generally, a water / monomer ratio from 2: 1 to 0.7: 1 is used. The initiators of the polymerization which are used are in particular the customary persulfates, for example potassium peroxodisulfate, but redox systems are also convenient. The amount of initiators (for example, from 0.1 to 1% by weight, based on the total weight of the monomers) depends, in a known manner, on the desired molecular weight. The polymerization aids which can be used are the normal buffer substances capable of setting a pH preferably from 6 to 9, for example sodium bicarbonate and sodium pyrophosphate, and from 0.1 to 3% by weight of a molecular weight regulator, such as a mercaptan, terpinol or dimeric a-methylstyrene. The precise conditions of the polymerization, in particular the type, the form of addition and the amount of the emulsifier, are determined within the ranges already provided so that the resulting latex of the crosslinked acrylate polymer (an) has a dso in the range from about 30 to 1000 nm, preferably from 50 to 900 nm.

The d5o of the particle size is defined in the normal way as the weighted average of the particle size as determined with an analytical ultracentrifuge by the method of W. Scholtan and H. Lange, Kolloid-Z. And Z.-Polymere 250 (1972) pp. 782-796. The ultracentrifuge measurement provides the distribution of the integral mass of the particle diameter of a specimen. From this it is possible to reduce the percentage by weight of the particles having a diameter equal to or less than a particular size. The average particle diameter, also called d50 of the integral mass distribution, is defined as the value at which 50% by weight of the particles have a smaller diameter and 50% by weight of the particles have a larger diameter that the d5o. Instead of the acrylate polymers (an), the grafted copolymers (A) can also comprise diene polymers (a? 2) as the base of the graft. The polymers (a? 2) are copolymers of dienes which, in addition to 60 to 100% by weight, preferably from 70 to 99% by weight, of one or more dienes, preferably butadiene or isoprene, can also contain up to 40% by weight. weight, preferably from 2 to 30% by weight, of other copolymerizable monomers, convenient examples of which are the alkyl acrylates described above in part (a) and the monomers (an3) copolymerizable with (a); for more details, reference is made to the description of these points. If the grafted core (ai) has to be a diene polymer, a useful procedure is as follows: the elastomer, the grafted base (ai2) are prepared by polymerizing the components (ai2?) And (a? 22) in aqueous emulsion in a known per se at a temperature of from 20 to 100 ° C, preferably from 50 to 90 ° C. Use may be made of the emulsifiers, polymerization initiators and other polymerization aids already described for the preparation of the acrylate polymer (an), for example buffers and molecular weight regulators, in the amounts mentioned in this section. The specific conditions for the polymerization selected within the aforementioned ranges for preparing the diene polymer (a? 2), in particular the type, dosage form and emulsifier amount, are such that the resulting latex of the diene polymer (a? 2) has a value d50 (see above) in the range from about 50 to 750 nm, preferably in the range from 70 to 600 nm. Alternatively, it is also possible to agglomerate an emulsion polymer with an average particle size in the range from 60 to 150 nm, as described in FIG.

DE-A 24 279 60, for example. A graft (a2) is grafted onto the graft base (au) and / or (ai2) and is obtained by copolymerizing: (a2?) from 50 to 95% by weight, preferably from 60 to 90% by weight, in particular from 62 to 85% by weight, based on (a2), of a vinylaromatic monomer, preferably styrene or substituted styrenes of the formula I where R is C 1 -C 8 alkyl, hydrogen or halogen and R 1 is C 1 -C 8 alkyl or halogen, and n is 0, 1, 2 or 3, preferably styrene, α-methylstyrene, p-methylstyrene or tert-butylstyrene , and (a22) from 5 to 50% by weight, preferably from 10 to 40% by weight, and in particular from 15 to 38% by weight, based on (a2), of a polar, copolymerizable, polar monomer, selected from the group consisting of acrylonitrile, methacrylonitrile, C?-C 4 alkyl (meth) acrylates, maleic anhydride and maleimides, and (meth) acrylamide, and / or vinylalkyl (of C?-C8) ethers, or mixture thereof .

In the second embodiment of the invention, the proportion of the components (a2i) and (a22) in the graft (a2) is: (a2?) From 65 to 95% by weight, preferably from 67 to 90% by weight, and in particular from 70 up 85% by weight, based on (a2), of a vinyl aromatic monomer mentioned above, and (a22) from 5 to 35% by weight, preferably from 10 to 33% by weight, and in particular from 15 to 30% by weight, based on (a2), of a monomer, polar copolymerizable, mentioned above. The grafted cover (a2) can be prepared in one or more steps, for example, in two or three steps, without resulting effect on its total constitution. The grafted cover is preferably prepared in emulsion, as described in DE-C 1 260 135, DE-A 32 27 555, DE-A 31 49 357, DE-A 31 49 358 and DE-A 34 14 118, by example. Depending on the conditions that are selected, there may be a certain proportion of styrene-acrylonitrile-free copolymers formed in the graft copolymerization. Again it is convenient to perform the graft copolymerization in the polymer which serves as the base of the graft (ai) in aqueous emulsion. This can be undertaken in the same system used for the polymerization of the graft base, in addition to the emulsifier and initiator being added if required. These need not be identical with the emulsifiers and initiators that are used for the preparation of the grafted base (ai). For example, it may be convenient to use a persulfate as an initiator to prepare the graft base (ai) but employ a redox initiator system to polymerize the grafted shell (a2). Otherwise, the relevant factors for the selection of the emulsifier, initiator and polymerization aids are those that are provided for the preparation of the graft base. (ai) The monomer mixture to be grafted can be added to the reaction mixture all at once, in batches in several steps or preferably continuously during the polymerization. The grafted base is conveniently controlled in such a way that the degree of formation of the resulting graft is from 10 to 60% by weight, preferably from 15 to 55% by weight. The graft copolymer (A) ((a?) + (A2)) in general has an average particle size preferably from 30 to 1000 nm, in particular from 100 to 900 nm (weighted average d50). Therefore, the conditions for the preparation of the elastomer (ai) and for the formation of the graft are preferably selected to give the particle sizes in this range. Measurements for these are known and described, for example, in DE-C-1 260 135 and DE-A 28 26 925 and in the Journal of Applied Polymer Science, vol. 9 (1965), pp. 2929-2938. The increase in particle size in the elastomer latex can be achieved, for example, by means of agglomeration. In some cases, mixtures of various acrylate polymers having different particle sizes have also shown good results. Products of this type are described in DE-A 28 26 925 and US Patent 5,196,480, to which reference may be made at this point for more details. Preferred mixtures of the acrylate polymers are therefore those in which a first polymer has a particle size dso in the range from 50 to 150 nm, and a second polymer has a particle size from 200 to 700 nm, as described in the aforementioned United States Patent 5,196,480. Preference is also given to the use of polymer blends (all) (as described in DE-A-ll 64 080, DE-PS 19 11 882 and DE-A 31 49 358) and polymers (ai 2), where the polymers (a? 2) in general have an average particle size in the range from 30 to 1000 nm, preferably from 100 to 900 nm. As component (B), the molding compositions of the invention contain from 1 to 90% by weight, preferably from 5 to 85% by weight, particularly preferably from 10 to 80% by weight, based on the total weight of the composition. the composition for molding, of a copolymer prepared from: (bi) from 50 to 99% by weight, preferably from 55 to 90% by weight, and in particular from 65 to 90% by weight 85% by weight, based on (B), of the vinylaromatic monomers, preferably styrene and / or substituted styrenes of the formula I and (b2) from 1 to 50% by weight, preferably from 10 to 45% by weight , and in particular from 15 to 35% by weight, based on (B), of the monomers described for (a22). In the second embodiment of the invention, the proportion of the components (bx) and (b2) in the component (B) is: (bi) from 69 to 81% by weight, preferably from 70 to 78% by weight, and in particular from 70 to 77% by weight, based on (B), of the aforementioned vinylaromatic monomers, and (b2) from 19 to 31% by weight, preferably from 22 to 30% by weight, particularly preferably from 23 to 30% by weight, based on (B), of the monomers described for (a22), acrylonitrile being used as component (b2), particularly preferably. Products of this type can be prepared by the methods described in DE-A 10 01 001 and DE-A 10 03 436, for example. Copolymers of this type are also commercially available. The average molecular weight determined by light scattering is preferably in the range from 40,000 to 500,000, in particular from 100,000 to 250,000 corresponding to the viscosity indexes in the range from 40 to 200 ml / g, preferably from 40 to 160 ml. / g (measured at a concentration of 0.5% by weight in solution in dimethylformamide at 25 ° C). The polymer (B) can also be a mixture of several styrene polymers respectively, a-methylstyrene and acrylonitrile, for example differing in their content of acrylonitrile or average molecular weight.

Based on the completeness of the components (A), (B), (C) and, as appropriate, (D) and (E), the proportion of the component (C) in the compositions for molding is from 1 to 70 % by weight, preferably from 1 to 50% by weight, and particularly preferably from 1 to 40% by weight. In the second embodiment of the invention, the proportion of the component (C) in the compositions for molding, based on the completeness of the components (A), (B), (C) and, as appropriate, (D) and (E), it is from 0.1 to 70% by weight, preferably from 0.1 to 50% by weight, and particularly preferably from 0.1 to 40% by weight. The proportion of the component (C) is very particularly preferably from 0.1 to 15% by weight, in particular from 0.5 to 15% by weight and very particularly from 1 to 15% by weight. Component (C) is an elastomeric block copolymer prepared from: at least one CA block forming a hard phase and having copolymerized units of a vinylaromatic monomer, and at least one elastomeric block C (BA> forming a soft phase and having units of a vinylaromatic monomer, and also of a diene where the glass transition temperature (Tg) of the CA block is above 25 ° C, preferably above 50 ° C, and that of block C (B / AJ is below 25 ° C, preferably below of 50 ° C, and the ratio of the selected phase-volume of the block C to the block C (B / AJ is such that the proportion of the phase lasts in all the block copolymer is from 1 to 40% by volume and the proportion by weight of the diene is lower than 50% by weight, where the ratio of the 1,2-linkages in the polydiene, based on the total of the 1,2- and 1,4-cis / trans bonds, is below 15%, preferably below 12%.

Detailed information on the structure and preparation of component C has been described in DE-A 19 615 533, which is incorporated herein by reference. Preferred vinylaromatic compounds are styrene and also α-methylstyrene, 1,1-diphenylethylene and vinyltoluene, and also mixtures of these compounds. The preferred dienes are butadiene and isoprene, and also piperylene, 1-phenylbutadiene and also mixtures of these compounds. A particularly preferred monomer combination is butadiene and styrene.

All the following weight and volume data are based on this combination. If the industrial equivalents of styrene and butadiene are used, the data has to be converted appropriately when necessary. An example of the structure of the block C (B / A) is from 75 to 30% by weight of styrene and from 25 to 70% by weight of butadiene. It is particularly preferable that the soft block has a portion from 35 to 70% by weight of butadiene and a proportion of from 65 to 30% of styrene. For the combination of styrene / butadiene monomers, the proportion of the diene by weight throughout the block copolymer is from 15 to 65% by weight, and that of the vinylaromatic component is from 85 to 35% by weight. Particular preference is given to butadiene-styrene block copolymers having a monomer comprised from 25 to 60% by weight of diene and from 75 to 40% by weight of vinylaromatic compound. Examples of a C-block copolymer are any of formulas 1 to 11: (2) (CA-C (B / A))? _CA (3) C (B / A) ~ (Cft-C (B / A) )) n (4) X - [(CA-C {B / A)) n3m + 1 (5) X- [(C (B / A) ~ CA) n.m + 1 (6) X- [(CA-C (B / A))? ~ C] ra + 1 (7) X- [(C (B / A) -CA) n ~ C (B / A)] m + l (8) Y - [(CA-C (B / A)) n] m + l (9) Y- [(C (B / A) -CA) n.m + l (10) Y- [(CA-C (B / A)) n-CA] m + l (11) Y- [(C (B / A) -CA) n ~ C (B / A)] m + l where CA is the vinylaromatic block and C (B / A) is the soft phase, that is, the block constructed at random from units of diene and vinylaromatic units, X is the residue of a functional n initiator, and Y is the residue of a functional coupling agent m, ymyn are natural numbers from 1 to 10. Preference is given to the block copolymers of one of the formulas CA-C (B / A) -CA, X- [-C (B / A) -CA] 2 and Y- [-C (B / A) -CA] 2 (the meaning of the abbreviations being as in the above), and particular preference is given to a block copolymer whose soft phase is subdivided into the following blocks (12) C (B / A) 1_C (B / A) 2- (13) C (B / A) 1 ~ C (B / A) 2 ~ C (B / A) 1 (14) C (B / A) 1-C (B / A) 2-C (B / A) 3 where the blocks have different structures and / or the vinylaromatic / diene ratio in the individual blocks C (B / A) changes in such a way that there is a gradient of the constitution C (B / A) P? «C (B / A) p2« C (B / A) p3 ... in each subsection (sub-block), the glass transition temperature Tg of each sub-block being below 25 ° C. Block copolymers of this type, which within a C (B / A) block have, for example, repeated sections p (sub-blocks) whose accumulation of monomers varies can be formed by adding the monomers in the portions p, where p is whole from 2 to 10. The addition in portions may be useful for controlling the flow of heat within the reaction mixture, for example. Preference is also given to a block copolymer each of whose molecules has two or more C (B / A) blocks and / or each of different molecular weight. It is also possible for a CB block to take the place of a CA block constructed exclusively from vinylaromatic units, since the essential point is that only one elastomeric block copolymer is formed. Examples of the structures of the copolymers of this type are (15) to (18) (15) CB-C (B / A) (16) C (B / A) -CB-C (B / A) (17) ) C (B / A) 1-CB-C (B / A) 2 (18) CB [C (B / A) iC (B / A) 2] Polymers "block" are prepared by anionic polymerization in a non-polar solvent, with initiation by organometallic compounds. Preference is given to the compounds of the alkali metals, particularly lithium. Examples of the initiators are methyl lithium, ethyl lithium, propyl lithium, n-butyl lithium, sec-butyl lithium and tert-butyl lithium. The organometallic compounds are in the form of a solution in a chemically inert hydrocarbon when it is added. The amount added depends on the desired molecular weight of the polymer, but in general it is from 0.002 to 5 mol%, based on the monomers. Preferred solvents that are used are aliphatic hydrocarbons such as cyclohexane or methylcyclohexane. Within the block copolymer, random blocks containing aromatic vinyl and diene are prepared with the addition of a soluble potassium salt, in particular a potassium alkoxide. It is very likely here that the potassium salt enters the metal exchange with the lithium-carbanion ion pair, giving potassium carbonations, which preferably form addition products with styrene, while the lithium carbanions preferably form addition products with butadiene . Since potassium carbanions are significantly more reactive, even a small fraction, specifically from 1/10 to 1/40, is probably sufficient along with the predominant lithium carbanions to return the average styrene incorporation equal to that of butadiene. It is also possible that during the polymerization process there is frequent metallic exchange between the latent chains, and also between latent chains and the dissolved salt, so that the same chain forms a preferential addition product with styrene on a particular occasion, and subsequently in turn with butadiene. The result is then that the parameters of the copolymerization for styrene and butadiene are approximately identical. Particularly convenient potassium salts are potassium alkoxide, and in particular in this case tertiary alkoxides having at least 7 carbon atoms. Examples of the common alcohols corresponding to these are 3-ethyl-3-pentanol and 2,3-dimethyl-3-pentanol. Tetrahydrolinalool (3,7-dimethyl-3-octanol) has been found to be particularly convenient. In addition to the potassium alkoxides, other potassium salts which are inert to the metal alkyl compounds are also convenient in principle. It should be mentioned in this case of potassium dialkylamides, alkylated potassium diarylamides, alkylthiolates and alkylated arylthiolates. The binding in which the potassium salt is added to the reaction medium is important. The monomer for the first block and at least some of the solvent are normally present in the initial charge in the reaction vessel. It is not advisable to add the potassium salt in this joint, since traces of protic contaminants hydrolyze at least some of the salt to give KOH and alcohol, and the potassium ions have then been irreversibly deactivated for polymerization. The lithium organo compound must, therefore, be first added and mixed, and then only the potassium salt. If the first block is a homopolymer, it is advisable not to add the potassium salt until shortly before polymerizing the random block. It is possible to easily prepare the potassium alkoxide from the corresponding alcohol by stirring a solution of cyclohexane in the presence of an excess of sodium / potassium alloy. After 24 hours at 25 ° C the evolution of hydrogen has ended, and with it the reaction. However, the reaction time should also be reduced by refluxing at 80 ° C for a few hours. A possible alternative reaction includes mixing the alcohol with a small excess of potassium methoxide, potassium ethoxide or potassium tert-butoxide in the presence of an inert solvent with high boiling point, such as decalin or ethylbenzene, distilling the alcohol with low point of boiling, in this case methanol, ethanol or tert-butanol, diluting the residue with cyclohexane and filtering to remove excess alkoxide of low solubility. The addition of the potassium compound usually achieves a ratio of 11 to 9% 1.2 bonds, based on the total of the 1,2 and 1,4 bonds in the diene. On the contrary, when a Lewis base is used according to DE-A 44 20 952, the values reached for the ratio of the 1,2 and 1,4 bonds in the diene units are from 15 to 40% for the links 1,2 and from 85 to 60% for the 1,4 links, for example, based in each case on the total amount of the copolymerized diene units. The polymerization temperature can be from 0 to 130 ° C, preferably from 30 to 100 ° C. The proportion of the soft phase constructed from sequences of dienes and from vinylaromatic sequences is from 60 to 95% by volume, preferably from 70 to 90% by volume and particularly preferably from 80 to 90% by volume. The CA blocks produced from the vinylaromatic monomers form the hard phase, the proportion of which in volume is in correspondence from 5 to 40%, preferably from 10 to 30% and particularly preferably from 10 to 20%. It should be noted that because each of the numerical values has been rounded there is no precise agreement between the ratios of the aforementioned quantities of the vinylaromatic compound and the diene, the threshold values of the volumes of the previously established phases and the constitution involved. by the intervals of the vitreous transition temperature according to the invention. If this were the case it would be just coincidence [sic]. The ratio of the two phases in volume can be measured by electron microscopy with phase contrast or solid state NMR spectroscopy. After the degradation of the osmium of the polydiene fraction, the proportion of the vinylaromatic blocks can be determined by precipitation and weight. If the polymerization is always allowed to proceed until its completion, the ratio of the future phase of a polymer can be calculated from the amounts of the monomers that are used. For the purposes of the invention, the block copolymers are defined interchangeably by the quotient calculated from the percentage by volume ratio of the soft phase formed by the C (B / A) blocks and the proportion of the diene units in the soft phase, which for the styrene / butadiene combination is from 25 to 70% by weight. The vitreous transition temperature (Tg) is influenced by the random incorporation of the vinylaromatic compounds into the soft block of the block copolymer and by the use of potassium alkoxides during the polymerization. The vitreous transition temperature is usually from -50 to +25 ° C, preferably from -50 to + 5 ° C. The vitreous transition temperature of the potassium-catalyzed random copolymers of the invention is on average smaller by from 2 to 5 ° C than in the case of the corresponding Lewis base-catalyzed products, since the latter have a higher proportion of 1,2 bonds of butadiene. The vitreous transition temperature of 1,2-polybutadiene is greater by about 70-90 ° C compared to that of 1,4-polybutadiene. The molar mass of the CA block in this case is, in general, from 1000 to 200,000, preferably from 3000 to 80,000 [g / mol]. The CA blocks within a molecule can have different molar masses. The molar mass of block C (B / A) is usually from 2000 to 250,000 [g / mol], preferred values being from 5000 to 150,000 [g / mol].

Like the Cñ blocks, the C (B / A) blocks can take different values of the molar mass within a molecule. The coupling center X is formed by reaction of the ends of the latent anionic chain with a coupling agent at least bifunctional. Examples of these compounds are found in US-A 3 985 830, 3 280 084, 3 637 554 and 4 091 053. Preference is given to the use of, for example, epoxidized glycerides, such as linseed oil or oil soybean epoxidized; Divinylbenzene is also convenient. Dichlorodialkylsilanes, dialdehydes such as terephthaldehyde, and esters such as ethyl formate or benzoate, are specifically suitable for dimerization. The preferred polymeric structures are CA-C (B / A) -CA; X - [- C (BA) -CA] 2 and Y- [-C (BA) -CA] 2, and the random block (B / A) may have been subdivided in this case into blocks C (BI / AI) -C (B2 / A2) -C (B3 / A3) ... The random block is preferably composed of from 2 to 15 random sub-blocks, particularly from 3 to 10 sub-blocks. The subdivision of the random block C (B / A) into the large number of sub-blocks CBn / An gives the decisive advantage that the sub-block C (B / A) total block behaves like an almost perfect random polymer even if there is continuous change (gradient) in its constitution within a sub-block CBa / An / 'in view of the fact that it is difficult to avoid in the anionic polymerization under industrial conditions (see below). As is evident, one possibility is to add less than the theoretical amount of potassium alkoxide. Some proportion of the sub-blocks can be given a fraction of high dienes [sic]. This has the effect that the polymer retains a residual impact resistance, even below the glass transition temperature of the predominant C (B / A) blocks and does not become completely brittle. The profile of the properties of the block copolymers of the invention is very similar to that of plasticized PVC, but these are prepared completely without the use of low molecular weight plasticizers that can migrate. These resist crosslinking under normal processing conditions (from 180 to 220 ° C). The excellent resistance of the polymers of the invention to crosslinking can be demonstrated unambiguously by rheography [sic]. The experimental arrangement corresponds to that of the MVR measurement. The increase in pressure as a function of time is recorded at a constant melt flow rate. Even after 20 minutes at 250 ° C, the polymers of the invention show no increase in pressure and give a smooth extrudate, while for a comparative specimen prepared in accordance with DE-A 44 20 952 with tetrahydrofuran the pressure under them conditions increases by a factor of three and the extrudate has a barbed wire appearance, usually observed when crosslinking occurs. The polymerization is carried out in two or more stages and in the case of monofunctional initiation, for example, it begins with the preparation of a hard block CA. A portion of the monomers is first placed in the reactor, and the polymerization is initiated by adding the initiator. To obtain a specific chain structure that can be calculated from the amounts of the monomer and the added initiator, it is advisable to take the process to a high conversion (above 99%) before adding the second monomer, but this is not a primary requirement. The monomer addition sequence depends on the structure of the selected block. In the case of monofunctional initiation, the vinylaromatic compound is an initial charge, for example, or is dosed directly. Then a solution of potassium alkoxide in cyclohexane is added. Then the diene and vinyl aromatics should be added simultaneously, if possible. The addition can take place in two or more portions. The relationship between the amount of diene and the vinylaromatic compound, and also the concentration of the potassium salt and the temperature, cause the random structure and determine the constitution of block C (B / A). The proportion by weight of the diene, in relation to the entire weight including the vinylaromatic compound, is from 25 to 70%. The CA block can then be polymerized by addition of the vinylaromatic. As an alternative, the required polymer blocks can also be linked together by a coupling reaction. In the case of bifunctional initiation, block C (B / A) is constructed first, followed by block CA. Follow the treatment by normal processes. The procedures that are advisable in this case are to work in a mixing vessel and use an alcohol, such as isopropanol, to finish the polymerization, use C02 / water in a traditional way to prepare the weakly acidic mixture before treatment, stabilize the polymer with an oxidation inhibitor and a free radical scavenger (commercially available products such as trisnoninophenyl phosphite (TNPP) or a-tocopherol (vitamin E) and / or products obtainable under the brand name Irganox 1076 or Irganox 3052) eliminate the solvent by the normal processes and perform the extrusion and obtain the pellets. As component (D) the thermoplastic molding compositions of the invention may comprise from 0 to 300% by weight, based on the completeness of (A), (B) and (C), preferably from 0 to 200% by weight, of at least one polycarbonate. Examples of suitable polycarbonates are those based on diphenols of the formula II where Z is a single bond, C 1 -C 3 alkylene, C 2 -C 3 alkyldiene, C 3 -C 6 cycloalkyldiene, -S- or -S0 2. Preferred diphenols of the formula II are, for example, 4,4'-dihydroxydiphenyl, 2,2-bis (4-hydroxyphenyl) -propane, 2,4-bis (4-hydroxyphenyl) -2-methylbutane and 1,1 -bis (4-hydroxyphenyl) cydohexane. Particular preference is given to 2,2-bis (4-hydroxyphenyl) propane and 1,1-bis (4-hydroxyphenyl) cydohexane. The homopolycarbonates and copolycarbonates are suitable as component (D); in addition to bisphenol A homopolymer, preference is also given to bisphenol A copolycarbonates. Convenient polycarbonates can be branched in a known manner, preferably by incorporation, from 0.05 to 2.0 mole%, based on the total the diphenols used, of at least trifunctional compounds, for example those having three or more phenolic OH groups. The polycarbonates which are suitable as component (D) can, in addition, be mono- to trisubstituted in aromatic form with halogen, preferably with chlorine and / or bromine, but particular preference is given to the compounds without halogen. Polycarbonates that have proved particularly convenient are those that have relative viscosities? Re? from 1.10 to 1.50, in particular from 1.25 to 1.40. This corresponds to the average molecular weights Mw (weighted average) from 10,000 to 200,000, preferably from 20,000 to 80,000. The diphenols of formula II are known per se or can be prepared by known processes. The polycarbonates can be prepared, for example, by reaction of the diphenols with phosgene in the interfacial process or with phosgene in the process in homogeneous phase (the process of pyridine), the molecular weight that is established in each case being obtained in a known form using an appropriate amount of the known chain terminators. (For polycarbonates containing polydiorganosiloxanes see, for example, DE-A 33 34 782.). Suitable chain terminators are, for example, phenol, p-tert-butylphenol and long-chain alkylphenols, such as 4- (1,3-tetramethylbutyl) phenol as in DE-A 28 42 005 or monoalkylphenols or dialkylphenols with from 8 to 20 carbon atoms in the alkyl substituents as in DE-A 35 06 472, such as p-nonylphenol, 3,5-di-tert-butylphenol, p-tert-octylphenol, p-dodecylphenol, 2- (3 , 5-dimethylheptyl) phenol and 4- (3,5-dimethylheptyl) phenol. Other suitable polycarbonates are those based on hydroquinone or resorcinol. In addition to the components (A), (B), (C) and (D), the thermoplastic molding compositions can also contain additives and processing aids such as the component (E) in amounts from 0 to 30% by weight, with based on the total weight of the compositions for molding. Additives and process aids of this type are lubricants and mold release aids, pigments, dyes, flame retardants, antioxidants, light stabilizers, fillers and reinforcing agents of a fibrous or powdery nature, and antistatic agents, in the normal amounts for these agents.

The molding compositions according to the invention can be prepared by mixing the processes known per se, for example by melting in an extruder, Banbury mixer, mixer, roller mill or calender. The components can, however, also be mixed "cold" without melting, and mixing in the form of a powder or consisting of granules fused and homogenized only in the processing step. Therefore, the present invention also provides a process for the preparation to a process for the preparation of the thermoplastic molding compositions of the invention by mixing the components and combining the processes known per se. From the compositions for molding it is possible to produce molded parts of any type, in particular films and flat articles. The films can be produced by extrusion, lamination, calendering and other processes known to the person skilled in the art. The molding compositions according to the invention are formed by heating and / or by friction, by themselves or with the addition of plasticizers or other additives, to obtain a film that can be further processed or a flat article (sheet). An example of a processing method for obtaining three-dimensional molded parts of any type is injection molding. The present invention, therefore, also offers the use of the thermoplastic molding compositions of the invention to produce moldings, films or fibers. Molded pieces that can be obtained using the compositions for thermoplastic molding are also provided. The thermoplastic molding compositions of the invention have better creep than comparable molding compositions together with better demolding and thermoformability and show no reduction in coating capacity and are largely free of vaporizing or exuding constituents. If (A) is a butadiene rubber, the molding compositions have excellent puncture resistance and impact strength in a notched specimen. If (A) is an acrylate rubber, the very good resistance to shock is a particular characteristic that should be highlighted. These are suitable for producing films, molded parts, (especially sheets) and fibers, with excellent capacity for further processing by thermoforming, and also for the production of injection molded parts, especially for fast processing with short cycle times.

The molding compositions of the invention are suitable for use in electrical devices such as kitchen equipment, drawers, telephones, vacuum cleaners, monitor boxes, keyboards, electric lawn mowers, toy railroads, washing machines, dishwashers and refrigerators. . The molding compositions of the invention are also convenient for producing auto parts. An example of its use is in the interiors of automobiles, in the central consoles, the side panels of the doors, the tachometer boxes, fan nozzles, buttons and switches. They are also suitable for automotive exterior applications, such as wheel caps, exterior mirrors (pigmented, painted or electroplated), electroplated emblems, radiator grilles and aerodynamic deflectors. The molding compositions of the invention are also suitable for toys, profile extrusion, pipe extrusion, sheet or sheet extrusion, double and multi-layer extrusion and housing parts.

Examples The following constituents were prepared (all percentage data are% by weight) A: Preparation of the components A: The average particle size mentioned in the description of the component (A) is the weighted average of the particle sizes. The average diameter corresponds to the dso, according to which 50% by weight of all the particles have a smaller diameter, and 50% by weight a diameter larger than the diameter corresponding to the dso. To characterize the width of the particle size distribution, the do and the d90 are often set in addition to the d50. 10% by weight of all the particles are smaller, and 90% by weight are larger than the diode diameter. In the same way, 90% by weight of all the particles have a smaller diameter and 10% by weight a diameter larger than the diameter corresponding to the d90. The quotient Q = (dg0-d? 0) / d5Q is a measure of the width of the particle size distribution. For a smaller Q value, the distribution is narrower.

Al: Preparation of an AI component: A) Preparation of a graft base AIl: The preparation of the respective acrylate-based graft base (fam) + (au2)) was carried out according to the following general specification: 160 g of a mixture of 98% butyl acrylate and 2% dihydrodicyclopentadienyl acrylate (DCPA) were heated to 60 ° C, with stirring, in 1500 g of water, with the addition of 5 g of the sodium salt of a C 2 -C 8 paraffinsulfonic acid, 3 g of potassium peroxodisulfate, 3 g of sodium bicarbonate and 1.5 g of sodium pyrophosphate. 10 minutes after the start of the polymerization, another 840 g of butyl acrylate were added for 3 hours. After the monomer addition was complete, the emulsion was maintained at 60 ° C for another hour.

B: Preparation of a particulate graft polymer A-I: 2100 g of the emulsion prepared in accordance with specification a) were mixed with 1150 g of water and 2.7 g of potassium peroxodisulfate and heated to 65 ° C with stirring. After the reaction temperature was reached, 560 g of styrene / a'crylonitrile in a ratio of 75:25 were added for 3 hours.

When the addition was complete, the emulsion was maintained at 65 ° C for another two hours. The graft polymer was precipitated from the emulsion using the calcium chloride solution at 95 ° C, washed with water and dried in a stream of hot air.

A2: Preparation of a component A-II: a) Preparation of a graft base A-II-1: The preparation of the respective butadiene-based graft base ((ai2?) + (A? 22)) was carried performed according to the following specification A polybutadiene latex is prepared by polymerization at 65 ° C of 600 g of butadiene in the presence of 6 g of ter-dodecyl mercaptan, 7 g of sodium C 14 alkyl sulphonate as an emulsifier, 2 g of potassium peroxodisulfate and 2 g of sodium pyrophosphate in 800 ml of water. The conversion is 98%. The resulting latex had an average particle size of 100 nm. This latex is agglomerated by adding 25 g of an emulsion of a copolymer of 96 parts of ethyl acrylate and 4 parts of methacrylamide, with a solids content of 10% by weight, producing a polybutadiene latex with an average particle size of 350 nm. b) Preparation of a particulate graft polymer A-II: After the addition of 400 g of water, 4 g of sodium C 4 alkyl sulphonate and 2 g of potassium peroxodisulfate to the graft base prepared in the specification a 400 g of a mixture of styrene and acrylonitrile (3: 1) are introduced over a period of 4 hours. The polymerization takes place at 75 ° C with stirring of the mixture. The conversion, based on styrene-acrylonitrile, is practically quantitative. The dispersion of the resulting grafted rubber is precipitated by means of a solution of magnesium sulfate and the grafted copolymer, isolated, is washed with distilled water and dried.

A3: Preparation of a component A-III: a) Preparation of a graft base A-III-1: 4312 g of butadiene are polymerized at 65 ° C in the presence of 43 g of tert-dodecyl mercaptan, 31.1 g of the salt of potassium of C? 2-C2o fatty acids, 8.2 g of potassium persulfate, 14.7 g of sodium acid carbonate and 5840 g of water to obtain a polybutadiene latex. The procedure is as described in EP-A 0 062 901. The conversion is 96%, and the average particle size is from 80 to 120 nm.

To agglomerate the latex, 3500 g of the resulting dispersion are mixed at 65 ° C with 287 g of a dispersion (solids content 10% by weight) prepared from 96% by weight of ethyl acrylate and 4% by weight of methacrylamide. b) Preparation of a particulate graft polymer A-III: 930 g of water, 13 g of the potassium salt of the C ?2-C2o fatty acids and 1.7 g of potassium peroxodisulfate are added to the resulting agglomerated latex. 897 g of a mixture of styrene and acrylonitrile (80: 20% by weight) are then added over a period of 4 hours. The dso of the particle size distribution of the resulting grafted dispersion is from 150 to 350 nm.

A: Preparation of component A-IV: a) Preparation of a graft base A-IV-1 4 parts of vinyl methyl ether, 15 parts of butyl acrylate and 15 parts of butadiene are heated to 65 ° C, with stirring, in 150 parts of water with the addition of 1.2 parts of the sodium salt of a paraffinsulfonic acid (C? 2-C? 8), 0.3 parts of potassium persulfate, 0.3 parts of sodium bicarbonate and 0.15 parts of sodium pyrophosphate. Once the polymerization has begun, a mixture prepared from 43 parts of butyl acrylate and 23 parts of butadiene is added over a period of 5 hours. Once all the monomers have been added, the polymerization mixture is maintained at 65 ° C for another 2 hours. This provides an aqueous dispersion of about 40% concentration. b) Preparation of a particulate graft polymer A-IV 250 parts of the dispersion of the first stage (graft base) (A-IV-1) are mixed with 60 parts of a prepared mixture of styrene and acrylonitrile and sufficient water to form a dispersion at 40% concentration, and polymerize at 70 ° C with stirring. 0.2% of potassium persulfate and 0.3% of lauroyl peroxide -in each case based on the monomer- are added as polymerization initiator and are dissolved in the monomer mixture.

B: Preparation of component B: The preparation of component B was carried out by the continuous solution polymerization process as described in Kunststoff-Handbuch, Ed. R. Vieweg and G.

Daumiller, vol. V "Polystyrol 'Carl-Hanser-Verlag, Munich 1969, pp. 122-124.

Bl: Component BI: A copolymer of styrene and acrylonitrile having 35% by weight of acrylonitrile (AN) and a viscosity index of 60 ml / g, measured as a solution at 0.5% concentration in dimethylformamide according to DIN 53726. B2 : Component B-II: A copolymer of styrene and acrylonitrile with 25% by weight of acrylonitrile and a viscosity index of 64 ml / g, measured as a solution at 0.5% concentration in dimethylformamide according to DIN 53726.

B3: Component B-III: As component B2, but with a viscosity index of 80 ml / g, measured as 0.5% solution in dimethylformamide according to DIN 53726.

B4: Component B-IV: As Bl, but with a viscosity index of 80 ml / g, measured as 0.5% concentration solution in dimethylformamide according to DIN 53726.

C: Preparation of component C: To prepare component C, a 50-liter stainless steel autoclave equipped with a cross-blade stirrer and simultaneous heating and cooling system was prepared by flooding with nitrogen and blanching with a solution of sec-butyl lithium and 1,1-diphenylethylene in a molar ratio of 1: 1 in cyclohexane, and drying. 22.8 1 of cyclohexane were then charged and the amounts given in Table 1 of the initiator, monomers and potassium alkoxide were added. The polymerization time is also provided, as is the initial temperature Tx and the final temperature TF, the monomer feed time always being short in relation to the polymerization time. The temperature of the reaction mixture was controlled by heating or cooling the jacket of the reactor. Once the reaction was over (the monomers had been consumed) it was titled ethyl formate until the mixture was colorless, and the mixture was acidified with an excess of 1.5 times the formic acid. Finally, 34 g of a commercially available stabilizer (© Irganox 3052, Ciba-Geigy, Basle) and 82 g of trisnonylphenyl phosphite were added. The solution was treated in a ventilated extruder (three vents, front and rear ventilation) at 200 ° C. The resulting granules were used to prepare the molding composition.

Table 1: Polymerization and analysis of an S-SB-S block copolymer (Component C) Mn [g / mol • 10 ~ 3] Lg ,? [° C] MD [g / mol 10"3] Mw [g / mol« 10 ~ 3] a .. [° C] 136 000 -55 to -25 158 000 (delta Cp 68%] 163 000 60 to 100 (delta Cp 32%; The average molar masses (in g / mol) of the polymer were determined by gel permeation chromatography (calibrated against polystyrene). Mn in this case means numerical average, Mv means average viscosity [sic], and Mw means weighted average. The glass transition temperatures Tg were determined by DSC and were from -55 to -25 ° C for the soft phase and from +60 to + 100 ° C for the hard phase. The melt volume index MVI was determined at 200 ° C with a load of 5 kg according to DIN 53 735, and was 8.5 ml / 10 min.

Compositions for thermoplastic molding The compositions for molding of the invention and the comparative compositions were prepared at 250 ° C and 200 rpm, in a yield of 10 kg / h, in a ZSK 30 extruder by Werner and Pfleiderer. The product was cooled in a water bath, granulated and injection molded in an Arburg Allrounder injection molding machine to obtain the test specimens. The elongation to break was tested in accordance with DIN 53504. The results for the first embodiment of the present invention are listed in the following Tables 2 and 3. The results for the second embodiment of the invention are listed in Tables 4 to 8 below.

Table 2 Table 3 The creep of the molding compositions was determined in the granules, through the melt flow volume index MVR (melt volume ratio) at 220 ° C with a load of 10 kp [sic]. The data provided are the quantities in ml charged through a normal nozzle in 10 minutes. The charpy shock resistance was measured in accordance with ISO 179 / leU, in specimens for tension of 4 mm dimension. The shock resistance in a charpy notched specimen was measured in test specimens of dimensions 80 x 10 x 4 mm molded at 240 ° C melt temperature / 60 ° C mold temperature with milled notch, tested in accordance with ISO 179 / leA . '?' The puncture resistance was measured in accordance with ISO 6603. Thermal resistance: determined in accordance with DIN 53 460 as Vicat value, using test method A.

Table 4 11 nm: not measurable 2 »nf: without fractures Table 5 Table 6 nf: no fracture Table 7 x) was not determined The results show that, even if the amounts of the component C are small, there is an increase in the strength of the coatings, without (if the amounts are small) substantial deterioration of other properties of the compositions for molding.

Table 8 1) resistance to shocks in a specimen with IZOD notch perpendicular to the extrusion direction 2) impact resistance in a specimen with IZOD notch parallel to the extrusion direction.

A comparison of the test resistances with IZOD notch between the molding compositions without the addition of component C (1) and those that have addition of component C (2) shows a marked improvement in impact resistance in notched specimen IZOD perpendicular to the extrusion direction with addition of component C.

Claims (3)

1. . A composition for thermoplastic molding containing: (A) from 5 to 98% by weight, based on the total weight of the composition for molding, of an elastomeric graft copolymer consisting of: (ax) from 30 to 90% by weight, based on (A), a grafted base with a glass transition temperature (Tg) below -10 ° C, prepared from: (an) an at least partially crosslinked acrylate polymer formed from: (m) from 50 to 99.9% by weight, based on (au) of at least one Ci-Cio alkyl acrylate (an2) from 0.1 to 5% by weight, based on (an), of at least one polyfunctional crosslinking monomer, and (an) from 0 to 49.9% by weight, based on (au), of another monomer that is copolymerizable with (am) selected from the group consisting of vinylalkyl (of C? -8) ethers, butadiene, isoprene, styrene , acrylonitrile and methacrylonitrile, and / or methyl methacrylate and / or (ai2) a diene polymer consisting of: (ai2i) from 60 to 100% by weight, based on (a? 2), of at least one diene, and (ai22) from 0 to 40% by weight, based on (a? 2) of other copolymerizable monomers selected from the group which consists of the alkyl acrylates of Ci-Cio, vinylalkyl (of Ci-Cs) ethers, butadiene, isoprene, styrene, acrylonitrile and methacrylonitrile, and / or methyl methacrylate. (a2) from 10 to 70% by weight, based on (A), of a graft with a (Tg) above 50 ° C, grafted on the base for grafting and consisting of: (a2?) from 50 to 95% by weight based on (a2), from at least one vinylaromatic monomer (a22) from 5 to 50% by weight, based on (a2), of at least one polar comonomer, copolymerizable, selected from the group consisting of: acrylonitrile, methacrylonitrile (meth) acrylates of C1-C4 alkyl, maleic anhydride and maleimides, and (meth) acrylamide and / or vinylalkyl ( Ci- C8) ethers, or a mixture of these (B) from 1 to 90% by weight, based on the total weight of the molding composition, of a copolymer composed of: (bi) from 50 to 99% by weight , based on (B), of at least one vinylaromatic monomer. and (b2) from 1 to 50% by weight, based on (B), of monomers as described for (a22), (C) from 1 to 70% by weight, based on (A), (B) , (C) and, as appropriate, (D) and (E), of an elastomeric block copolymer composed of: at least one CA block forming a hard phase and having copolymerized units of a vinylaromatic monomer, and at least one elastomeric block C (B / A) forming a soft phase and having copolymerized units of a vinylaromatic monomer, and also of a diene where the vitreous transition temperature (Tg) of the CA block is above 25 ° C and the of block C (B / A) is below 25 ° C, and the selected phase-volume relationship of the CA block to the C block (B / A) is such that the proportion of the phase lasts throughout the block copolymer is from 1 to 40% by volume and the weight ratio of the diene throughout the block copolymer is less than 50% by weight where the ratio of the 1, 2 bonds in the polydiene, based on the total of the 1,2- and 1,4- cis / trans bonds is below 15% and (D) from 0 to 300% by weight , based on the weight of the components (A) to (C) of a polycarbonate. (E) from 0 to 30% by weight, based on the total weight of the composition for molding, of the traditional additives and processing aids.
2. 2. A composition for thermoplastic molding containing: (A) from 5 to 98% by weight, based on the total weight of the molding composition, of at least one elastomeric graft copolymer consisting of: (ax) from 30 to 90% by weight weight, based on (A), of a grafted base with a glass transition temperature (Tg) below -10 ° C, prepared from: (au) an at least partially crosslinked acrylate polymer formed from: (a) ) from 50 to 99.9% by weight, based on (an) of at least one Ci-Cio alkyl acrylate (am) from 0.1 to 5% by weight, based on (an), of quartz minus a polyfunctional crosslinking monomer, and (an3) from 0 up to 49.9% by weight, based on (au), of another monomer which is copolymerizable with (am) selected from the group consisting of vinylalkyl (of C? -8) ethers, butadiene, isoprene, styrene, acrylonitrile and methacrylonitrile, and / or methyl methacrylate and / or (a? 2) a diene polymer consisting of: (a) from 60 to 100% by weight, based on (ai2), of at least one diene, and (ai22) from 0 to 40% by weight, based on (a? 2) of other copolymerizable monomers selected from the group consisting of the alkyl acrylates of Ci-Cio, vinylalkyl (of C? -8) ethers, butadiene, isoprene, styrene, acrylonitrile and methacrylonitrile, and / or methyl methacrylate (a2) from 10 to 70% by weight, based on (A), of a graft with a (Tg) above 50 ° C, grafted s on the basis for grafting and consisting of: (a2?) from 50 to 95% by weight based on (a2), from at least one vinylaromatic monomer (a22) from 5 to 35% by weight, based on (a2), of at least one polar comonomer, copolymerizable, selected from the group consisting of: acrylonitrile, methacrylonitrile, methyl) C 1 -C 4 alkyl acrylates, maleic anhydride and maleimides, and (meth) acrylamide and / or vinylalkyl (of Ci- C8) ethers, or a mixture of these (B) from 1 to 90% by weight, based on the total weight of the molding composition, of a copolymer composed of: (bi) from 69 to 81% by weight, based on (B), of at least one vinylaromatic monomer. and (b2) from 19 to 31% by weight, based on (B), of monomers as described for (a22), (C) from 1 to 70% by weight, based on (A), (B) , (C) and, as appropriate, (D) and (E), of an elastomeric block copolymer composed of: at least one CA block forming a hard phase and having copolymerized units of a vinylaromatic monomer, and at least one elastomeric block C (B / A) forming a soft phase and having copolymerized units of a vinylaromatic monomer, and also of a diene where the vitreous transition temperature (Tg) of the CA block is above 25 ° C and that of the C block (B / A) is below 25 ° C, and the selected phase-volume relationship of block Cj to block C (B / A) is such that the proportion of the phase lasts throughout the block copolymer is from 1 to 40% by volume and the weight ratio of the diene throughout the block copolymer is less than 50% by weight where the ratio of the 1, 2 bonds in the polydiene, based on the total of the 1,2- and 1,4- cis / trans bonds is below 15% and (D) from 0 to 300% by weight , based on the weight of the components (A) to (C) of a polycarbonate, of S-NA copolymers (styrene-maleic acid copolymers), of S-imide-MA copolymers (styrene-imide-maleic anhydride copolymers) , of copolymers S-imide-AN-MA (copolymers of styrene-imide-acrylonitrile-maleic anhydride), of a polymethacrylamide or of a polymethacrylate, and (E) from 0 to 30% by weight, based on the total weight of the composition for molding, the additives and traditional processing aids.
3. 3. The composition for thermoplastic molding as claimed in claim 2, wherein the proportion of the component (C) is from 0.1 to 15% by weight, based on (A), (B), (C) and, as appropriate (D) and (E). The composition for thermoplastic molding as claimed in any of claims 1 to 3, wherein a graft copolymer with a graft base (a? 2) is used as component (A). The composition for thermoplastic molding as claimed in any of claims 1 to 4, wherein the ratio of the 1,2 bonds in the polydiene in the component (C) is below 12%, based on the total of the 1,2- and 1,4-cis / trans bonds. The composition for thermoplastic molding as claimed in any of claims 1 to 5, wherein the glass transition temperature Tg of the CA block in component (C) is above 50 ° C and that of block C (B / A) ) is below 5 ° C. The composition for thermoplastic molding as claimed in any of claims 1 to 6, wherein the vinylaromatic monomer in component (C) has been selected from the group consisting of styrene, α-methylstyrene, vinyltoluene, 1,1-diphenylethylene and mixtures of these compounds, and the diene has been selected from the group consisting of butadiene, isoprene, piperylene, 1-phenylbutadiene and mixtures of these compounds. The composition for thermoplastic molding as claimed in any of claims 1 to 7, wherein the component (C) has one of the formulas 1 to 11 [sic]: (12) (CA-C (B / A)) n (13) (CA-C (B / A)) n ~ CA (14) C (B / A) - (CA-C (B / A)) n (15) X- [(Ca-C (B /?)) n_m + l (16) X- [(C (B / A) -CA) n] m + l (17) X- [(CA-C (B / A)) n ~ CA] m +? (18) X- [(C (B / A) -CA) n ~ C (B / A)] m + l (19) Y - [(CA-C (B / A)) n.m + 1 ( 20) Y - [(C (B / A, -CA) n] m +? (21) Y- [(CA-C (B / A)) n "C] m + l (22) Y- [(C (B / A) _CA) nC (B / A)] m + l where CA is the vinylaromatic block and C (B / A) is the soft phase, that is, the block constructed at random from diene units and of vinylaromatic units, X is the residue of a functional n-initiator, Y is the residue of a functional coupling agent m and m and n are natural numbers from 1 to 10. The thermoplastic molding composition as claimed in any of claims 1 to 8, wherein the molar mass of the CA block in component (C) is from 1000 to 2000 and that of block C (B / A) is from 2000 to 250,000 [g / mol]. A process for preparing compositions for thermoplastic molding as claimed in any of claims 1 to 9, which consists in mixing the components by combining the processes known per se. The use of a thermoplastic molding composition as claimed in any of claims 1 to 9 for producing films, castings or fibers. A molded part that can be obtained using a thermoplastic molding composition as claimed in any of claims 1 to 9.