WO1999037688A1

WO1999037688A1 - Microsuspension (graft)polymers and method for producing same

Info

Publication number: WO1999037688A1
Application number: PCT/EP1999/000392
Authority: WO
Inventors: Graham Edmund Mckee; Heiner GÖRRISSEN; Michael Fischer; Walter Kastenhuber
Original assignee: Basf Aktiengesellschaft
Priority date: 1998-01-21
Filing date: 1999-01-21
Publication date: 1999-07-29
Also published as: DE19802093A1

Abstract

The invention relates to a rubber-elastic microsuspension polymer A1 with a mean particle diameter of between 0.08 and 100 νm, consisting of components A11 to A13, the total weight of which amounts to 100 weight percent, where a11 is between 1 and 100 weight percent monomers with a solubility in water of less than 0.01 % at 23 °C as component A11, a12 is between 0 and 99 weight percent additional copolymerisable monomers as component A12, and a13 is between 0 and 10 weight percent cross-linking monomers as component A13.

Description

Microsuspension (graft) polymers and process for their preparation

The invention relates to microsuspension (graft) polymers, processes for their preparation, their use and molding compositions containing them.

Emulsion polymerization has long been used to produce small-particle polymer particles. It is a heterogeneous reaction process in which unsaturated monomers or monomer solutions are emulsified in a continuous phase, usually water, with the aid of an emulsifier system and polymerized with initiators which form free radicals. A colloidal dispersion of the polymer or the polymer solution, a so-called latex, is obtained as the product. During the reaction, the emulsifier system forms micelles into which the at least partially water-soluble monomers from the emulsified monomer droplets migrate through the water phase. With the help of initiators contained in the water phase, the polymerization is triggered in the micelles. The monomers used must have a certain water solubility in order to be able to migrate from the monomer droplets through the aqueous phase into the micelles. Examples of monomers that can be used are styrene, butadiene, acrylic acid, vinyl chloride, acrylonitrile and others. A corresponding procedure is described in Encyclopedia of Polymer Science and Engineering, Volume 6, page 1 (1986), John Wiley & Sons, New York.

However, if largely water-insoluble monomers are polymerized with the aid of the emulsion polymerization, a coagulate is formed from the emulsified monomer droplets, since the water-insoluble monomer cannot migrate from the monomer droplets through the water phase to the micelles. It is therefore not possible to obtain finely divided polymers from such monomers without special precautions. An attempt has been made to use, in addition to the sparingly water-soluble monomers, other compounds which are capable of building up a supramolecular structure and which associate with the water-insoluble monomer. The association with the water-insoluble monomer improves the water diffusibility of the monomer, so that the transport from the monomer droplets into the micelles can take place. Such a method is described in DE-A-195 48 038. Cyclodextrins, for example, are used as supramolecular structures.

However, this process is not generally suitable for the polymerization of poorly water-soluble or water-insoluble monomers. In addition, parts of the compound with a supramolecular structure can be contained in the finished polymer.

The object of the present invention is to provide a process for the production of particulate polymers of sparingly or not water-soluble monomers which avoids the disadvantages of the known processes.

The object is achieved according to the invention by a rubber-elastic microsuspension polymer AI with an average particle diameter of 0.08 to 100 μm from components All to A13, the total weight of which is 100% by weight, all: 1 to 100% by weight of monomers a water solubility of less than

0.01% at 23 ° C as component All, al2: 0 to 99% by weight of further copolymerizable monomers as component A12. al3: 0 to 10% by weight of crosslinking monomers as component A13.

The object is also achieved by a microsuspension graft polymer A from al: 1 to 99.9% by weight of a graft core, as defined above, as component AI, a2: 0.1 to 99% by weight of at least one graft shell from an organic Polymer as component A2. - 3 -

It has been found according to the invention that highly water-insoluble monomers, which in particular cannot be polymerized by emulsion polymerization, can be polymerized by the microsuspension polymerization process. Strongly water-insoluble monomers can be polymerized together with further, optionally water-soluble, monomers. The polymers obtained can be used to make matrix polymers impact-resistant, matt and hydrophobic. They can also be used for the production of moldings, fibers and films or for the treatment of, for example, paper, textiles, leather and other materials, for example in order to improve their hydrophobic properties.

The process of microsuspension polymerization is described, for example, in DE-A-44 43 886.

A method for producing the above microsuspension (graft) polymers is preferred

(1) dispersing the monomers corresponding to the microsuspension polymer AI in water using a protective colloid to give a dispersion having an average particle diameter of 0.08 to 100 μm,

(2) Polymerization of the droplets with a radical polymerization initiator up to a conversion of more than 50%, based on the amount of the monomers, and if appropriate

(3) Graft polymerization of the mixture obtained in step (2) in the presence of monomers of component A2.

The (graft) polymers according to the invention are preferably obtained as follows: The liquid monomer or liquid monomer mixture which is to be polymerized to give the particulate (core) polymer is mixed with water and a protective colloid. The (preferably water-insoluble) polymerization initiator is either counteracted either now or only after the monomers have been dispersed. - 4 -

also added after heating the dispersion. A dispersion of tiny monomer droplets in water is produced from the heterogeneous mixture by intensive stirring at high speed with strong shear. Intensive mixers of any type are suitable for this. The desired particle size can be determined, for example, by taking light micrographs and counting the number of particles which have a specific diameter.

The polymerization is started by heating the dispersion. The reaction with moderate stirring, during which the droplets are no longer broken up, is continued until the conversion, based on the amount of monomers originally used, is above 50%, preferably above 85%.

If a microsuspension polymer consisting of only one core is desired, the reaction can be terminated at this stage. If a microsuspension graft polymer is desired, the reaction with the monomers from which the corresponding shells are to be made is continued in a manner known per se. The grafting can also be started when the polymerization conversion of the core monomers is still incomplete and above 50%, preferably above 85%. In this case, the shell and core form a more fluid transition compared to the sharper demarcation of core and shell polymer in the event that the core monomers are initially completely converted.

In this way, single- or multi-shell polymers can be obtained. This can also depend on the particle size desired. Processes for the preparation of multi-shell graft copolymers are described, for example, in EP-A-0 548 762. If the graft cores are relatively small and it is desired to introduce a larger amount of the core polymer into the particles, multi-shell graft copolymers can also be produced in which one of the shells is built up from the core monomers. - 5 -

The monomers are generally dispersed at a temperature of 0 to 100 ° C., preferably at about room temperature. As a rule, 0.2 to 10 kg of water are used per kg of monomers.

The protective colloids suitable for stabilizing the dispersion are water-soluble polymers which coat the monomer droplets and the polymer particles formed therefrom and in this way protect against coagulation.

Protective colloids are cellulose derivatives such as carboxymethyl cellulose and hydroxymethyl cellulose, poly-N-vinyl pyrrolidone, polyvinyl alcohol and polyethylene oxide, anionic polymers such as polyacrylic acid and cationic polymers such as poly-N-vinyl imidazole. The amount of these protective colloids is preferably 0.1 to 5% by weight, based on the total mass of the monomers of the core. In addition, low molecular weight surface-active compounds, for example of the anionic or cationic soap type, can also be used. Such compounds, which are usually used for emulsion polymerizations, are described, for example, in "Emulsion Polymerization and Emulsion Polymers", published by P.A. Lovell and M. El-Aasser, John Wiley & Sons, Chichester (1997), pages 224 to 227.

Free radical initiators are suitable as polymerization initiators, in particular those which are soluble in the monomers and which preferably have a half-life of 10 hours when the temperature is between 25 and 150 ° C. Such initiators are described, for example, in the AKZO "Initiators for Polymer Production" product catalog. For example, peroxides such as lauryl peroxide, peroxosulfates, tert-butyl perpivalate and azo compounds such as azodiisobutyronitrile are suitable.

In addition to the oil-soluble radical formers, preferably dilauryl peroxide, benzoyl peroxide and 2,2'-azo-bis-isobutyronitrile, small amounts of water-soluble ones can also be used Initiators such as hydrogen peroxide, potassium, ammonium and sodium peroxide are used, in particular if smaller particles of less than 1.0 μm are also to be obtained.

Various initiators can be used to produce the graft core and the graft shells. The amount of initiators is generally 0.1 to 2.5% by weight, based on the amount of monomers.

Furthermore, the reaction mixture preferably contains buffer substances, such as Na ₂ HPO ₄ / NaH ₂ PO ₄ or Na citrate / citric acid, in order to set an essentially constant pH. In addition, molecular weight regulators, such as ethylhexyl thioglycolate or decenyl mercaptan, are generally added during the polymerization, in particular of the monomers which make up the shells.

The temperature in the polymerization of the monomers of the core is generally 25 to 150 ° C., preferably 50 to 120 ° C. The shells are generally grafted onto the core at a temperature of 25 to 150 ° C., preferably 50 to 120 ° C. The lower limit values of these ranges correspond to the decomposition temperatures of the polymerization initiators used in each case.

The microsuspension polymer AI has an average particle diameter of 0.08 to 100 μm, preferably 0.2 to 50 μm, particularly preferably 0.3 to 30 μm. The particle size can be determined using different methods. For example, it is determined by light scattering. The light scattering method, as available from Leeds & Northrop, North Wales, PA, is preferred. It can also be used with devices from Particle Data, Elmhurst, Illinois, USA, for example with the ELZONE ^* 280PC system.

Component AI contains 1 to 100% by weight, preferably 3 to 100% by weight, particularly preferably 5 to 100% by weight of monomers with a water solubility of less than 0.01% at 23 ° C., preferably less than 0.007%, particularly preferably less than 0.005% as component All. The figures are% by weight and relate to the amount of water.

As component AI are preferably C ^ Q-alkyl methOacrylate, C ^ - Aralkyl (meth) acrylate, C ^ o-Ary me ^ acrylate,. ₂ o-alkaryl (meth) acrylate, α-olefins with 2 to 20 C atoms, polyisobutylenes with 3 to 50 isobutene units and optionally a terminal vinyl or vinylidene group, polypropylenes with a terminal vinyl or vinylidene group with 3 to 100 propylene units, oligohexene , Oligooctadecen, C _ισ40 -alkyl _vinyl ether, mono- or diesters of maleic acid or fumaric acid with Cg ^ -alkanols, vinyl esters of saturated C _1M0 -carboxylic acids or mixtures thereof.

Monomers whose water solubility is not above the water solubility of n-octyl acrylate are particularly preferably used. C ₈ are particularly preferred. ₃₀ -, in particular C ^. ^ - Alky me ^ acrylate, in particular alkyl (meth) acrylates which are derived from fatty acid residues.

Further preferred compounds are. ^ - Aralkyl net acrylate, C ^ o- aryl (meth) acrylate, C ₇ . ₂ o-alkaryl (meth) acrylate, α-olefins with 6-20 C atoms, polyisobutylenes with 5-30 isobutene units and possibly a terminal vinyl or vinylidene group, polypropylenes with a terminal vinyl vinylidene group with 7-30 propylene units, C _10.24 -Alkyl vinyl ether and vinyl esters of saturated C ₁₀ . ₂₄ carboxylic acids.

The monomers of component All can be polymerized without comonomers or copolymerized with monomers of components A12 and A13. For example, 0 to 99% by weight, preferably 0 to 97% by weight, particularly preferably 0 to 95% by weight, of further copolymerizable monomers - 8th -

can be used as component A12. These can be comonomers polymerizable with the emulsion polymerization (free radical). For example, .g-alkyl meth acrylates, preferably n-butyl acrylate and / or 2-ethylhexyl acrylate, can be used. Styrene, α-methylstyrene, acrylonitrile and methacrylonitrile can also be used. Other suitable comonomers are described in Ulimann's Encyclopedia of Industrial Chemistry, 4th Edition, Volume 19, pages 1-30, Verlag Chemie, Weinheim.

In addition, 0 to 10% by weight, preferably 0 to 8% by weight, particularly preferably 0 to 6% by weight, of crosslinking monomers can be used as component A13. Examples of this are bifunctional and polyfunctional comonomers such as butadiene and isoprene, divinyl esters of dicarboxylic acids such as succinic acid and adipic acid, diallyl and divinyl ethers, bifunctional alcohols such as ethylene glycol or butane-l, 4-diol, diesters of acrylic acid and methacrylic acid with the bifunctionalelles Alcohols, 1,4-divinylbenzene and triallyl cyanurate. The acrylic ester of tricyclodecenyl alcohol is particularly preferred

(Dihydrodicyclopentadienyl acrylate), as well as allyl esters of acrylic acid and methacrylic acid.

If shells are present on the polymer cores, the microsuspension graft polymers A of this type are from 1 to 99.9% by weight, preferably 10 to 99.5% by weight, particularly preferably 40 to 99% by weight, one as above described graft core as component AI and 0.1 to 99% by weight, preferably 0.5 to 90% by weight, particularly preferably 1 to 60% by weight, of at least one graft shell composed of a polymer as component A2. Component A2 may in particular be styrene, α-methylstyrene, acrylonitrile, methacrylonitrile, (meth) acrylic acid ester or mixtures thereof. If the microsuspension graft polymers are to be incorporated into matrix polymers, the outermost shell preferably corresponds to the matrix polymer or is compatible or partially compatible with it. A very low degree of grafting is predominantly reactive groups that can react with the polymer matrix, for example. Examples are (meth) acrylic acid and glycidyl (meth) acrylate, which can react with polyamides, for example.

The particulate graft polymers according to the invention serve mainly as additives to brittle, thermoplastic, macromolecular base materials (polymer matrix). The invention also relates to a molding composition of this type comprising components A to D, the total weight of which gives 100% by weight, a: 1 to 85% by weight, preferably 2 to 80% by weight, of at least one microsuspension graft polymer described above as component A, b: 15 to 99% by weight, preferably 20 to 98% by weight, of a polymer matrix, for example Polyamide, polyester, polyoxymethylene or preferably a polymer made from styrene, α-methylstyrene, acrylonitrile, methacrylonitrile, (meth) acrylic acid esters or mixtures thereof as component B, c: 0 to 50% by weight, preferably 0 to 40% by weight, fibrous or particulate fillers or mixtures thereof as component C, and d: 0 to 40% by weight, preferably 0 to 30% by weight, of further additives as component D.

By adding component A, the impact strength of the molding composition is improved. On the other hand, caused by diffuse reflection (scattering) of the light on the large particles, molding compounds with reduced surface gloss and correspondingly matt molded parts are obtained.

The rubber-elastic particles are incorporated into the melt of matrix B, so that the molding composition formed is composed of thermoplastic matrix B and the graft polymer particles dispersed therein. In order to make the core polymer elastomers AI compatible with the base polymer for the purposes mentioned, the rule is that the outermost shell and the matrix material B are compatible or partially compatible with one another. In many cases this means - 10 -

that their outer graft shell is made of the same or similar material as the base polymer. The technically most important base polymers are homopolymers of styrene, methyl acrylate, (C _M alkyl) methacrylates and acrylonitrile, copolymers of these monomers and other comonomers such as methacrylonitrile, ie these monomers and monomer mixtures are suitable depending on the structure of base polymer B. to build up the outer graft shell.

For example, if the outer shell is to be relatively hard, intermediate shells made of a less hard material can be recommended. Furthermore, the first hard grafting shell can be followed by a shell made of soft material, for example the core material, which can often further improve the properties of the thermoplastic molding compositions produced from the matrix B and the graft polymer particles A and the moldings produced therefrom. The relationships between the nature of both components in the molding compositions and the material properties correspond, moreover, to those known for the base material and graft polymers which are prepared by emulsion polymerization.

This also applies to base materials B other than those mentioned, e.g. Polyesters, polyamides, polyvinyl chloride, polycarbonates and polyoxymethylene. In these cases, compatible and partially compatible graft shells can be easily determined through a few preliminary tests.

Compatibility is understood as miscibility at the molecular level. One polymer is considered to be compatible with another if the molecules of both polymers are statistically distributed in the solid state, i.e. if the concentration of a polymer along any vector neither increases nor decreases. Conversely, it is considered incompatible if two phases are formed in the solid state, which are separated from one another by a sharp phase boundary. Along a vector intersecting the phase interface, the concentration of one polymer suddenly increases from zero to 100% and that of the other from 100% to zero. - 11 -

There are smooth transitions between the two extremes. They are characterized in that a phase boundary is formed, but this is not clear. At the interface, there is mutual partial penetration of the two phases. The concentration of one polymer therefore increases more or less rapidly from zero to 100% along a vector which intersects the phase boundary and that of the other polymer more or less rapidly from 100% to zero.

In this latter case, one speaks of partial compatibility, as it often occurs in technically important polymers.

Examples of partially compatible polymers are the pairs of polymethyl methacrylate / copolymer from styrene and acrylonitrile, polymethyl methacrylate / polyvinyl chloride and polyvinyl chloride / copolymer from styrene and acrylonitrile, and the three-phase system polycarbonate / polybutadiene / copolymer from styrene and acrylonitrile (= polycarbonate / ABS).

More information on the concept of compatibility of polymers and in particular the so-called solubility parameter as a quantitative measure is e.g. the Polymer Handbook, ed. J. Brandrup and E.H. Immergut, 3rd edition, Wiley, New York 1989, pp. VII / 519-Vπ / 550.

For graft modification, the graft polymers according to the invention are generally used in amounts of 1 to 85, preferably 2 to 80,% by weight, based on the amount of their mixture with the base polymer. Shaped bodies made from such mixtures are highly light-scattering and therefore particularly matt to opaque.

If a matting effect with still high transparency is desired, concentrations of 2 to 10% by weight of the graft polymers are recommended. There with these - 12 -

low concentrations would only result in a relatively small increase in impact strength, in this case it is possible to use conventional, very finely divided rubber-elastic modifying agents in the amounts customary for this, minus the amount of the graft polymer according to the invention used as a matting agent.

In addition, opaque polymers which already contain modifying agents which make impact, for example styrene-acrylonitrile copolymer (= ABS) modified with polybutadiene, styrene-acrylonitrile copolymer (= ASA) modified with polyalkyl acrylate, or with ethylene-propylene-diene Monomer (EPDM) modified styrene-acrylonitrile copolymer (= AES) can be matted by using the graft polymers according to the invention.

The particles according to the invention achieve a matting effect, often without impairing mechanical properties, as can be observed with conventional matting agents such as chalk or silica gel.

The protective colloids used in the production of the core polymers have, because of their higher molecular mass and greater space filling of the molecules, much less effort than the low molecular weight emulsifiers to migrate to the surface of the plastic. High molecular protective colloids are therefore far less likely to exude from a molded part.

In addition, the molding compositions modified with the particles according to the invention and the moldings produced therefrom have the advantages of improved printability and so-called anti-blocking properties, ie the surfaces of the moldings “roughened” by the particles do not adhere to one another. This effect due to adhesion is known, for example, from plastic films. Films containing particles according to the invention and layered on top of one another in a stack can be separated from one another without any problems, in contrast to films which do not contain such particles. - 13 -

The molding compositions can contain fibrous or particulate fillers or mixtures thereof as component C. Examples of these are carbon fibers or glass fibers, for example made of E, A or C glass. They can preferably be equipped with a size and an adhesion promoter. Other fillers or reinforcing materials are glass balls, mineral fibers, whiskers, aluminum oxide fibers, mica, quartz powder and wollastonite.

The molding compositions can also contain additives of all kinds as component D. For example, Lubricants and mold release agents, pigments, flame retardants, dyes, stabilizers and antistatic agents, all of which are added in the usual amounts.

The molding compositions according to the invention can be prepared by mixing processes known per se, e.g. by incorporating the particulate graft polymer into the base material at temperatures above the melting point of the base material, in particular at temperatures of 150 to 350 ° C. in conventional mixing devices. Films, fibers and moldings with reduced surface gloss (mattness) and high impact strength can be produced from the molding compositions according to the invention. The polymer components do not separate in the films, fibers and moldings.

The invention is explained in more detail below with the aid of examples:

EXAMPLES

Particle size measurements:

The particle size distribution was determined using an Elzone ^® 28.0PC device from Particle

Data, Elmhurst Illinois, USA. - 14 -

The D (50) value is given for the following experiments.

The D (50) value is the value at which 50 volume percent of the particles are larger and 50 volume percent of the particles are smaller than this value.

example 1

(a) Preparation of the lauryl acrylate dispersion:

The following batch was stirred under nitrogen with a Dispermat at 7000 rpm for 20 minutes. The Dispermat came from VMA-Getzmann GmbH, D-51580 Reichshof and was provided with a 5cm tooth lock washer. This process was repeated and the two emulsions obtained were mixed.

Approach:

1182.8 g water

220.5 g of a 10% polyvinyl alcohol (PVA) solution in water

(PVA: degree of hydrolysis 88 mol%, viscosity according to DIN 53015 one

4% solution in water at 20 ° C: 8mPa / s, Mowiol 8-88 from Hoechst). 540.2 g of n-butyl acrylate

22.1 g dihydrodicyclopentadienyl acrylate

540.2 g lauryl acrylate

5.5 g dilauryl peroxide

100 g of these mixed emulsions were mixed in a moderately stirred (250

Rpm) glass flask placed under nitrogen at 66 ° C and polymerized. The remainder of the two emulsions were metered in over a period of 180 minutes. Polymerization was continued for 60 minutes.

(b) grafting the dispersion with styrene and acrylonitrile - 15 -

To the finished and stable dispersion from step (a) came 1714.6 g of water, followed by 151.4 g of a 10% strength Mowiol 8-88 solution in water, 1135.8 g of styrene and 378.6 g of acrylonitrile, where the monomers were added as a feed of 120 minutes. After a reaction time of 150 minutes, the mixture was cooled. The amount of coagulum was 1 g (moist).

The average particle size was 2.4 μm.

Example 2

Example 1 was repeated, but instead of 540.2 g of lauryl acrylate, 540.2 g became

Stearyl acrylate used.

The amount of coagulum was 10 g (moist).

The average particle size was 2.3 μm.

Example 3

Example 1 was repeated, but in addition 27.5 g of a 40% solution of the potassium salt of a C ₁₂ were used in the emulsification step. _lg -paraffin sulfonic acid in water (emulsifier K30) used per emulsifier.

The amount of coagulum was 1 g and the mean particle size was 0.52 μm.

Example 4

Example 3 was repeated, but stearyl acrylate was used instead of lauryl acrylate. The amount of coagulum was 3 g and the mean particle size was 0.52 μm.

Example 5 - 16 -

Example 4 was repeated, but instead of 540.2 g butyl acrylate and 540.2 g stearyl acrylate, 110.3 g butyl acrylate and 992.3 g stearyl acrylate were used. The amount of coagulum was 1 g and the mean particle size was 0.77 μm.

Example 6

Example 5 was repeated, but lauryl acrylate was used instead of stearyl acrylate. The amount of coagulum was 2 g.

Example 7

Example 4 was repeated, but instead of 540.2 g of butyl acrylate and 540.2 g of stearyl acrylate, 1080.5 g of lauryl acrylate were used. The amount of coagulum was 1 g.

Example V 8

The following emulsion polymerization was carried out:

(a) The initial charge was placed in a glass flask under nitrogen with moderate stirring and a reaction temperature of 65 ° C. and the feed was added in 100 minutes.

Template (without emulsification):

439.3 g of water 18.0 g of a 40% solution of the potassium salt of a C ₁₂ . _lg -

Paraffin sulfonic acid in water (emulsifier K30) 1.1 g potassium persulfate - 17 -

Intake:

176.4 g of n-butyl acrylate

7.2 g dihydrodicyclopentadienyl acrylate

176.4 g lauryl acrylate

The batch was polymerized for 60 minutes.

(b) grafting:

302.8 g of water and 1.0 g of potassium persulfate were added to the dispersion from stage (a). This was followed by an inflow of 185.1 g of styrene and 61.7 g of acrylonitrile over 90 minutes.

There was coagulation during the preparation of stage 1. The batch coagulated completely during grafting.

Example V 9

Example 8 was repeated, but with stearyl acrylate instead of lauryl acrylate.

Claims

- 18 patent claims

1. Rubber-elastic microsuspension polymer AI with an average particle diameter of 0.08 to 100 μm from components All to A13, the total weight of which is 100% by weight,

all: 1 to 100% by weight of monomers with a water solubility of less than

0.01% at 23 ° C as component All, al2: 0 to 99% by weight of further copolymerizable monomers as component

A12, al3: 0 to 10% by weight of crosslinking monomers as component A13.

2. Microsuspension graft polymer A.

al: 1 to 99.9% by weight of a graft core, as defined in claim 1, as component AI, a2: 0.1 to 99% by weight of at least one graft shell made of an organic polymer as component A2.

3. microsuspension graft polymer A according to claim 2, characterized in that polymers of styrene, α-methylstyrene, acrylonitrile, methacrylonitrile, (meth) acrylic acid esters or mixtures thereof are used as component A2.

4. microsuspension (graft) polymer according to one of claims 1 to 3, characterized in that as component All C ^^ - alkyl (meth) acrylate, ^ -Aralky me ^ acrylate, ^ -Arry metl acrylate,. ^ -Alkary metli acrylate, α-olefins with 2 to 20 C atoms, - 19 -

Polyisobutylenes with 3 to 50 isobutene units and optionally a terminal vinyl or vinylidene group, polypropylenes with a terminal vinyl or vinylidene group with 3 to 100 propylene units, oligohexene, oligooctadecene, C _1M0 -alkyl _vinyl ether, mono- or diester of maleic acid or fumaric acid with ^ -alkanols ,

Vinyl esters of saturated C _{1 (M0} carboxylic acids or mixtures thereof can be used.

5. microsuspension (graft) polymer according to any one of claims 1 to 4, characterized in that methoxyacrylates are used as component A12 C ^ -alky.

6. A process for the preparation of microsuspension (graft) polymers according to one of claims 1 to 5

(1) dispersing the monomers corresponding to the microsuspension polymer AI in water using a protective colloid to give a dispersion having an average particle diameter of 0.08 to 100 μm, (2) polymerizing the droplets with a radical polymerization initiator up to a conversion of over 50%, based on the amount of monomers, and optionally

7. Use of microsuspension (graft) polymers as defined in one of claims 1 to 5, in polymer molding compositions or for the treatment of paper, textiles or leather.

8. Molding composition containing components A to D, the total weight of which is 100 - 20 -

Wt% gives

a: 1 to 85% by weight of at least one microsuspension graft polymer according to one of claims 2-5 as component A, b: 15 to 99% by weight of a polymer matrix of a styrene polymer, α-

Methylstyrene, acrylonitrile, methacrylonitrile, (meth) acrylic acid esters or mixtures thereof as component B, c: 0 to 50% by weight of fibrous or particulate fillers or mixtures thereof as component C, and d: 0 to 40% by weight of further additives as component D.

9. Use of molding compositions according to claim 8 for the production of fibers, films or moldings.

10. Fibers, films or moldings from a molding composition according to claim 8.