DE102004019455A1 - Preparation of molding materials, useful to manufacture e.g. foils, comprises mixing thermoplastic matrix with rubber under evaporation of processed water to form an emulsion and simultaneously removing the organic volatile components - Google Patents

Abstract

Preparation of molding materials (I) (comprising thermoplastic matrix (T) and a rubber (K1) dispersed within (T)) comprises mixing of (K1) with (T) under evaporation of processed water to form an emulsion and simultaneously removing the organic volatile components in the reaction mixture, where (K1) (added in the reaction) is formed in an emulsion without prior draining of the solid material containing fluid (mixture (M1)).

Description

The The present invention relates to a process for the preparation of Molding compositions containing a thermoplastic matrix (T) and a therein dispersed rubber (K), by mixing, in one Step A) prepared in emulsion, K with T with evaporation of Process water and removal of other organic volatile Components simultaneously in a process room.

Further embodiments The present invention are the claims, the description and the To take examples. It is understood that the above and those to be explained below Features of the method according to the invention not only in the specified combination, but also in Other combinations are usable without the scope of the invention to leave.

One Problem in the production of rubber-modified thermoplastics The rubbers are especially fine in the thermoplastic Disperse matrix. Another known problem is such Blends as possible produce low energy.

A known process principle, is the thermoplastic Mix matrix with a rubber dispersion and in another Step to degas this mixture. A variant of this process principle is e.g. in the not pre-published Application DE-P 102004013008.6 described.

The US 3,700,622 discloses another variant of this type of process for the production of ABS. Accordingly, styrene-acrylonitrile copolymers (SAN) can be prepared from styrene and acrylonitrile in the presence of a solvent. After completion of the polymerization reaction, so this document, the resulting SAN reaction mixture can be further used as such or diluted with solvent. The resulting SAN solution is treated with a rubber dispersion. The SAN rubber mixture is subjected to shear forces, generally with coagulant added. Subsequently, the mixture is degassed in a degassing extruder and processed to the final product.

A process for the preparation of molding compositions from SAN and two different graft rubbers is the US 3,931,256 refer to. In this process, a mixture of SAN and a liquid phase of styrene and acrylonitrile can be used. One of the two rubbers is prepared by bulk polymerization and recovered as beads. The beads are dissolved in styrene and acrylonitrile. This solution will continue to be used in the process. The second rubber is prepared by emulsion polymerization and can be mixed according to a process variant with styrene, acrylonitrile and solvent extracts. From this mixture, the water is separated. The three solutions or dispersions are mixed and then degassed in two stages.

According to DE-A 2 400 659 can rubber-modified resins are prepared by adding a first preparation, the SAN block copolymers and the monomers the SAN block copolymer preparation contains, with a second preparation mixed and then be degassed by flash evaporation in a wiped film evaporator. The second Preparation can be obtained by using an emulsion prepared in emulsion Dried graft copolymer and then, for example, in a Mixture of styrene and acrylonitrile is dispersed.

To Another process principle is the rubber after its preparation first partially drained and mixed as a wet solid with the thermoplastic melt.

So DE-A 197 13 039 describes that the rubber in a first Stage mechanical, e.g. is drained by pressing or centrifuging. The moist elastomer is then in a second stage in the than Melt present thermoplastics mixed. Simultaneous and in a process space, which is preferably a large-volume kneading reactor, Adhesive process water and other volatile components are removed. Melting takes place simultaneously and in the same process room of the rubber and alloying the elastomer with the thermoplastic melt. A problem of this method is that by means of a corresponding It must be prevented that the elastomer with the hot ones Housing surfaces of the Kneading reactor in contact comes. Furthermore must be taken into account in the apparatus design that it in the process comes to powder fly. So that's the constructive options little flexible and limited.

task It was the object of the present invention to provide a further improved process for the preparation of molding compositions based on elastomer-modified Themolast are based. The process should have as much as possible allow fine dispersion of the rubber in the matrix. The energy expenditure should be as low as possible. Also was sought that the equipment cost small and the process should be feasible with flexible equipment. Especially should the disadvantages of the method disclosed in DE-A 197 13 039 be resolved.

Accordingly, a process for the preparation of molding compositions found that a thermoplastic matrix (T) and a rubber dispersed therein (K), by mixing, in a step A) in emulsion K produced with T under evaporation of process water as well Removal of other organic volatiles simultaneously in a process room characterized by being in emulsion prepared K after the manufacturing step A) without prior dehydration in the form of a solids-containing fluid (mixture M1) in the process space is introduced.

Thermoplastic matrix (T)

In the method according to the invention can in principle, all plastics that process thermoplastically and are themselves rubber-free, used as matrix (T) become. This also includes a mixture of two according to the invention or more different thermoplastic materials. The thermoplastic matrix may be e.g. to polyethylenes, Polypropylenes, polyesters, polyamides, polystyrenes, polymethyl methacrylates, Polycarbonates or polyarylenesulfides act, including copolymers such as statistical copolymers or block copolymers.

When Polyamides are partially crystalline, preferably linear, polyamides such as Polyamide-6, polyamide-6,6, polyamide-4,6, polyamide-6,12 and partially crystalline Copolyamides based on these components suitable. Furthermore, semicrystalline Polyamides are used, the acid component in whole or in part from adipic acid and / or terephthalic acid and / or isophthalic acid and / or suberic acid and / or sebacic acid and / or azelaic acid and / or dodecanedicarboxylic acid and / or a cyclohexanedicarboxylic acid, and their diamine component in whole or in part, in particular from m- and / or p-xylylenediamine and / or hexamethylenediamine and / or 2,2,4- and / or 2,4,4-trimethylhexamethylenediamine and / or isophoronediamine, and their compositions in the Principle known in the art.

preferred Polyesters are aliphatic polyesters, but also aromatic-aliphatic Polyester. Examples are polyalkylene terephthalates, e.g. based of ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol and 1,4-bis-hydroxymethylcyclohexane and terephthalic acid, as well Polyalkylene.

Farther can Polyoxyalkylenes, e.g. Polyoxymethylene be used.

Prefers are polycarbonates based on diphenyl carbonate and bisphenols. Preferred bisphenol is 2,2-di (4-hydroxyphenyl) propane, generally - as well in the following - as Bisphenol A called. In place of bisphenol A can also other aromatic dihydroxy compounds are used, in particular 2,2-di (4-hydroxyphenyl) pentane, 2,6-dihydroxynaphthalene, 4,4'-dihydroxydiphenylsulfane, 4,4'-dihydroxydiphenyl ether, 4,4'-Dihydroxydiphenylsulfit, 4,4'-dihydroxydiphenylmethane, 1,1-di- (4-hydroxyphenyl) ethane, 4,4-dihydroxydiphenyl or dihydroxydiphenyl cycloalkanes, preferably dihydroxydiphenylcyclohexanes or dihydroxylcyclopentanes, in particular 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane and mixtures of the aforementioned dihydroxy compounds. Especially preferred polycarbonates are those based on bisphenol A or bisphenol A together with up to 80 mol% of the aforementioned aromatic Dihydroxy compounds. It can also copolycarbonates are used; of special interest are copolycarbonates based on bisphenol A and di- (3,5-dimethyl-dihydroxyphenyl) sulfone, characterized by a high heat resistance distinguished.

To The preferred plastics that can be used as the matrix include polystyrenes and their copolymers, as well as poly (meth) alkyl acrylates, among which such with 1-8 C atoms in the ester are preferred.

For example it may be SAN (styrene-acrylonitrile), AMSAN (α-methylstyrene-acrylonitrile), styrene-maleimide-maleic anhydride (SNPMIMA), (styrene-maleic acid (anhydride) acrylonitrile polymers or SMSA (styrene-maleic anhydride), Styrene-methyl methacrylate copolymers, or styrene-α-methylstyrene-acrylonitrile terpolymers act.

• t1) 60 bis 100 Gew.-%, vorzugsweise von 65 bis 82 Gew.-%, Einheiten eines vinylaromatischen Monomeren, vorzugsweise des Styrols, eines substituierten Styrols oder eines (Meth)acrylsäureesters oder deren Gemische, insbesondere des Styrols oder α-Methylstyrols oder deren Mischungen,
• t2) 0 bis 40 Gew.-%, vorzugsweise von 18 bis 35 Gew.-%, Einheiten eines ethylenisch ungesättigten Monomers, vorzugsweise des Acrylnitrils oder Methacrylnitrils oder Methylmethacrylats, insbesondere des Acrylnitrils.

Preferably, the component is a copolymer, based on T,

• t1) 60 to 100 wt .-%, preferably from 65 to 82 wt .-%, units of a vinyl aromatic monomer, preferably of styrene, a substituted styrene or a (meth) acrylic acid ester or mixtures thereof, in particular of styrene or α-methylstyrene or their mixtures,
• t2) 0 to 40 wt .-%, preferably from 18 to 35 wt .-%, units of an ethylenically unsaturated monomer, preferably of the acrylonitrile or methacrylonitrile or methyl methacrylate, in particular of the acrylonitrile.

According to one embodiment In this case, the matrix polymer of the invention is from 60 to 99% by weight of vinylaromatic Monomers and 1 to 40 wt .-% of at least one of the other specified Monomers built.

According to one embodiment the invention is a copolymer of styrene and / or α-methylstyrene as the matrix polymer used with acrylonitrile. The acrylonitrile content in these copolymers is while 0 to 40 wt .-%, preferably 18 to 35 wt .-%, based on the total weight of T.

The Molecular weights (weight average Mw) are usually in Range of 50,000 to 500,000 g / mol, preferably in the range of 70 000 to 450 000 g / mol.

The Matrix polymers are known per se or can according to the expert known, methods are produced. The proportion of thermoplastic Matrix used in the molding compositions obtained by the method according to the invention can be produced, can vary widely. In general amounts it just as much as to produce certain product features (Toughness, Flowability) required is. Often the proportion of the thermoplastic matrix is in the range from 40 to 95% by weight, preferably in the range from 50 to 90% by weight, based on the total weight of the molding compound.

In the method according to the invention For example, the matrix can be used as such, i. that they are less as 5% by weight of volatile Ingredients has.

Prefers however, T is mixed with an organic solvent (Mixture M2) introduced into the process space. As organic solvents come a variety of organic liquids into consideration. The Choice of solvent depends on the type of matrix used. As a rule, solvents preferred, which also easily due to their vapor pressure can be thermally removed. As a solvent become special those preferred, in addition to the thermoplastic matrix also be able to keep the rubber in suspension or in which T or both T and K is partially or completely soluble. examples for organic solvents are acetone, ethers, such as tetrahydrofuran, alkyl acetate, butyl acetate, Ketones such as methyl ethyl ketone, ethylbenzene, toluene or xylene. It can Of course also solvent mixtures be used. It is possible, a separately manufactured Matrix with an organic solvent to mix. Preferably, however, the mixture M2) is that from the manufacturing process the matrix obtained reaction mixture. Preferably, the mixture comprises M2) therefore also monomers which originate from the production of the matrix. Preferably contains the mixture M2) the matrix, ethylbenzene, styrene or styrene derivatives and acrylonitrile. According to one of the preferred embodiments, M2) comprises styrene-acrylonitrile copolymer, Ethylbenzene, styrene and acrylonitrile. In general, the solids content is the mixture M2) in the range of 50 to 90 wt .-%, preferably from 55 to 85 wt .-% and particularly preferably from 60 to 80 wt .-%.

Rubber (K) and its manufacturing

through the method according to the invention can Moldings are prepared based on a rubber (K). This includes those that are a mixture of two or more different rubbers. The in the method according to the invention usable rubbers can be different nature. Thus, e.g. graft or rubbers are used with a block structure. The rubbers (K) generally have a glass transition temperature (determined according to DIN 53765) of 0 ° C or below. Particularly preferred are rubbers with the thermoplastic matrix are compatible. Among the preferred Counting rubbers Graft copolymers.

The graft copolymers each contain one, formed by a rubber, phase (soft phase) as a graft and a graft (hard phase). This is to be understood according to the invention as meaning that several soft and hard phases can be included. The graft copolymers can also be based on rubbers of various monomeric composition or have a different grafting. Furthermore, it is possible that they have both a different grafting base and a have different Pfropfauflage.

in principle are suitable as a graft base all rubbers that have a glass transition temperature from 0 ° C (determined according to DIN 53765) or below. The rubbers can be different nature. For example, silicone, olefin, such as Ethylene, propylene, ethylene / propylene, EP (D) M, block rubbers such as styrene / ethylene / butadiene / styrene (SEBS) rubbers, diene, acrylate, Ethylene vinyl acetate, or ethylene butyl acrylate rubbers.

Prefers are used as a grafting base acrylate and diene rubbers.

When Acrylate rubbers are mainly polymers of alkyl acrylates which account for up to 40% by weight, based on the total weight of the acrylic rubber, other copolymerizable monomer can. Preferred are C1 to C8 alkyl esters, e.g. Methyl, -, ethyl, butyl, n-octyl and 2-ethylhexyl esters or mixtures of said esters. Particular preference is given to crosslinking acrylate rubbers as the graft base used. The skilled worker is familiar with processes for their preparation. Your Particle diameters (weight average d50) are generally in the range of 0.05 to 10 μm, preferably from 0.1 to 5, in particular from 0.15 to 3 microns (determined according to W. Scholtan and H. Lange, colloid-Z. and Z.-Polymers 250 (1972) pages 782-796, by means of Ultracentrifuge).

• k11) 50 bis 100 Gew.-% mindestens eines Diens mit konjugierten Doppelbindungen und
• k12) 0 bis 50 Gew.-% von einem oder mehreren weiteren monoethylenisch ungesättigten Monomeren,

aufgebaut sind, wobei sich die Gewichtsprozente von k11) und k12) zu 100 addieren.However, diene rubbers are particularly preferably used as the graft base. Very particularly preferred as the graft base are diene rubbers which are made from

• k11) 50 to 100 wt .-% of at least one diene having conjugated double bonds and
• k12) 0 to 50% by weight of one or more further monoethylenically unsaturated monomers,

are constructed, wherein the weight percent of k11) and k12) add up to 100.

When Dienes with conjugated double bonds, k11), come in particular Butadiene, isoprene and their halogen-substituted derivatives, such as Chloroprene, into consideration. Preference is given to butadiene or isoprene, in particular Butadiene.

The other monoethylenically unsaturated monomers k12) which may be present in the diene rubber at the expense of the monomers k11) are, for example:
vinylaromatic monomers, preferably styrene or styrene derivatives such as C1 to C8 alkyl substituted styrenes such as α-methylstyrene, p-methylstyrene, vinyltoluene; unsaturated nitriles such as acrylonitrile, methacrylonitrile;
aliphatic esters such as C1 to C4 alkyl esters of methacrylic acid or of acrylic acid such as methyl methacrylate, furthermore also the glycidyl esters, glycidyl acrylate and methacrylate;
N-substituted maleimides such as N-methyl, N-phenyl and N-cyclohexylmaleimide; Acids such as acrylic acid, methacrylic acid; furthermore dicarboxylic acids such as maleic acid, fumaric acid and itaconic acid and also their anhydrides such as maleic anhydride; Nitrogen-functional monomers such as dimethylaminoethyl acrylate, diethylaminoethyl acrylate, vinylimidazole, vinylpyrrolidone, vinylcaprolactam, vinylcarbazole, vinylaniline, acrylamide and methacrylamide;
aromatic and araliphatic esters of (meth) acrylic acid and such as phenyl acrylate, phenyl methacrylate, benzyl acrylate, benzyl methacrylate, 2-phenylethyl acrylate, 2-phenylethyl methacrylate, 2-phenoxyethyl acrylate and 2-phenoxyethyl methacrylate; unsaturated ethers such as vinyl methyl ether or vinyl butyl ether.

Of course, come also mixtures of two or more of these monomers into consideration.

preferred Monomers k12) are styrene, acrylonitrile, methyl methacrylate, glycidyl acrylate, methacrylate or butyl acrylate.

The Production of the rubbers (K) takes place according to the invention in emulsion (Step A). According to the invention below be understood that the preparation in the presence of a liquid dispersant, preferred Water, takes place and a liquid or solid disperse fraction is present. Process for the preparation of rubbers in emulsion are known in the art or the preparation can be done by methods known to those skilled in the art.

So can for example, the diene rubbers used as a grafting base be made in a first step, where they not particulate incurred, for example via solution polymerization or gas phase polymerization and then in a second step in the aqueous Phase are dispersed (secondary emulsification).

For the production however, the rubbers are preferred for primary emulsification. So For example, the preparation may be e.g. in a conventional manner by the method Emulsion, Inverse Emulsion, Miniemulsion, Microemulsion, or microsuspension in the feed process, continuously or in batch mode become. The rubbers can also prepared in the presence of a submitted finely divided latex (so-called "seed latex procedure" of the polymerization). Suitable seed latices consist for example of polybutadiene or Polystyrene. In this way, grafting bases with monomodal, or, for example, by gradual addition of seed also bimodal distribution produce.

Basically it possible These rubbers after their production directly with the matrix mix or use directly as a grafting base. You can, however even before a grafting first through Agglomeration process to larger particles be agglomerated.

method for agglomeration are known in the art or agglomeration can be made by the skilled person known per se methods. So can physical processes such as freeze or pressure agglomeration processes be used. It can But also chemical methods are used to get the primary particles to agglomerate. The latter include the addition of inorganic or organic acids. Preference is given to agglomeration by means of an agglomeration polymer in the absence or presence of an electrolyte, such as an inorganic one Hydroxide, made. As Agglomerisationspoylmerisate are, for example To name polyethylene oxide polymers or polyvinyl alcohols. To the suitable agglomeration polymers include copolymers of C1- to C12-alkyl acrylates or C1 to C12 methalkyl acrylates and polar comonomers such as acrylamide, Methacrylamide, ethacrylamide, n-butylacrylamide or maleic acid amide.

Prefers the graft copolymers have particle sizes (weight average d50) in the range of 100 to 2500 nm. The particle size distribution can be independent influenced by the Saatlatex-driving also by the agglomeration become. The particle size distribution The graft copolymer is preferably almost or completely monomodal or in another preferred embodiment bimodal.

• k21) 50 bis 100, bevorzugt 60 bis 100 und besonders bevorzugt 65 bis 100 Gew.-% eines vinylaromatischen Monomeren,
• k22) 0 bis 50, bevorzugt 0 bis 40 und besonders bevorzugt 0 bis 35 Gew.-% Acrylnitril oder Methacrylnitril oder deren Mischungen,
• k23) 0 bis 40, bevorzugt 0 bis 30 und besonders bevorzugt 0 bis 20 Gew.-% von einem oder mehreren weiteren monoethylenisch ungesättigten Monomeren,

wobei sich die Anteile der Komponenten k21) bis k23) zu 100 Gew.-% ergänzen.The graft copolymers contain a grafting pad based on an unsaturated monomer, which also means that the grafting pad can be prepared from two or more unsaturated monomers. In principle, the rubbers can be grafted with a wide variety of unsaturated compounds. Corresponding compounds and methods are known per se to the person skilled in the art. Preference is given to containing a graft

• k21) from 50 to 100, preferably from 60 to 100, and particularly preferably from 65 to 100,% by weight of a vinylaromatic monomer,
• k22) 0 to 50, preferably 0 to 40 and more preferably 0 to 35 wt .-% of acrylonitrile or methacrylonitrile or mixtures thereof,
• k23) 0 to 40, preferably 0 to 30 and particularly preferably 0 to 20 wt .-% of one or more further monoethylenically unsaturated monomers,

wherein the proportions of components k21) to k23) add up to 100% by weight.

When vinylaromatic monomers are those mentioned under k12) vinyl aromatic Compounds or mixtures of two or more thereof, in particular Styrene or α-methylstyrene, into consideration. To the other monoethylenically unsaturated Counting monomers those listed under k12) aliphatic, aromatic and araliphatic esters, acids, nitrogen-functional Monomers and unsaturated Ethers or mixtures of these monomers.

In the graft pad can but also monomers containing functional groups, including in particular Epoxy or oxazoline are mentioned.

you The graft may be in one or more process steps produce. It can the monomers k21), k22) and k23) individually or in a mixture with one another added become. The monomer ratio The mixture may be constant in time or a gradient. Also Combinations of these procedures are possible.

For example you can do it first Styrene alone, and then a mixture of styrene and acrylonitrile, on polymerize the graft base.

Preferred graft coatings are for example of styrene and / or α-methyl-styrene and one or more of the other monomers mentioned under k22) and k23). Preference is given here to methyl methacrylate, N-phenylmaleimide, maleic anhydride and acrylonitrile, particularly preferably methyl methacrylate and acrylonitrile.

Preferred grafting conditions are based on: K2-1: styrene K2-2: Styrene and acrylonitrile, K2-3: α-methylstyrene and acrylonitrile, K2-4: Styrene and methyl methacrylate K2-5 Alkyl acrylate and methyl methacrylate k2-6 Styrene, α-methylstyrene and acrylonitrile

Especially is preferred the proportion of styrene or α-methylstyrene, or the proportion of the sum of styrene and α-methylstyrene, at least 40 Wt .-%, based on the Pfropfauflage.

Farther are suitable as already mentioned also graft copolymers with several "soft" and "hard" stages, especially in the case of larger particles.

• k1) 30 bis 95, bevorzugt 40 bis 90, insbesondere 40 bis 85 Gew.-% einer Pfropfgrundlage (d.h. Kautschuk) und
• k2) 5 bis 70, bevorzugt 10 bis 60, insbesondere 15 bis 60 Gew.-% einer Pfropfauflage

enthalten.Preference is given to graft copolymers which (based on the graft copolymer)

• k1) 30 to 95, preferably 40 to 90, in particular 40 to 85 wt .-% of a graft base (ie rubber) and
• k2) 5 to 70, preferably 10 to 60, in particular 15 to 60 wt .-% of a graft

contain.

• k1) 30 bis 95 Gew.-% einer Pfropfgrundlage, enthaltend (bezogen auf b1)) 90 bis 100 Gew.-% Butadien und 0 bis 10 Gew.-% Styrol

und

• k2) 5 bis 70 Gew.-% einer Pfropfauflage, enthaltend (bezogen auf b2)) von 65 bis 85 Gew.-% Styrol und von 15 bis 35 Gew.-% Acrylnitril

enthalten.Examples of preferred graft copolymers are those which (based on the graft copolymer)

• k1) from 30 to 95% by weight of a grafting base comprising (based on b1)) from 90 to 100% by weight of butadiene and from 0 to 10% by weight of styrene

and

• k2) from 5 to 70% by weight of a grafting pad containing (based on b2)) from 65 to 85% by weight of styrene and from 15 to 35% by weight of acrylonitrile

contain.

• k1) 30 bis 95 Gew.-% einer Pfropfgrundlage, enthaltend n-Butylacrylat und einen Vernetzter

und

• k2) 5 bis 70 Gew.-% einer Pfropfauflage, enthaltend (bezogen auf Pfropfauflage) von 65 bis 85 Gew.-% Styrol und von 15 bis 35 Gew.-% Acrylnitril

enthalten.The preferred graft copolymers include, for example, those which (based on K)

• k1) 30 to 95 wt .-% of a grafting base containing n-butyl acrylate and a crosslinked

and

• k2) 5 to 70 wt .-% of a graft, containing (based on grafting) of 65 to 85 wt .-% of styrene and 15 to 35 wt .-% of acrylonitrile

contain.

According to the invention Grafting done in emulsion. Suitable procedural measures are known to the skilled person. As far as not grafted in the grafting Polymers formed from the monomers k2), these amounts, the usually less than 20 wt .-%, preferably less than 10 wt .-%, based on graft copolymer associated with the mass of the matrix (T).

in the General amounts the solids content of the emulsion of 30 obtained in step A) to 70 wt .-%, preferably from 40 to 70 wt .-% and particularly preferably from 50 to 65% by weight, for example 55 to 65% by weight. The others Ingredients are generally water and in the polymerization the rubber added additives such as emulsifiers or stabilizers.

According to the invention, the rubber produced in emulsion after the production step A) is used without prior dehydration. This means that, for example, the rubber is not isolated from the reaction mixture by the addition of coagulants, such as salts, or by measures such as squeezing, centrifuging or centrifuging. A phase transition to the wet rubber does not take place. Erfindungsge Instead, a solids-containing fluid (mixture M1) is used instead. If more than one rubber is used in the process, these different rubbers are used either in the form of the same fluid and so that the mixture M1) introduced into the process space contains more than one rubber. However, it is also possible for each of the rubbers to be present in the form of a fluid, so that more than one mixture M1) is present, which is supplied to the process space separately from one another. Preference is given to the former variant.

The Mixture M1) can be used in different ways in the process space be introduced. Thus, the metered addition may e.g. done gravimetrically. According to the invention For example, the mixture M1) is preferably conveyed by means of a pump solids-containing fluids is suitable, introduced into the process space. These are preferably valve-free pumps. For example, peristaltic pumps, Progressing cavity pumps, poppy or centrifugal pumps used become. According to one of the preferred embodiments Pumps are used with a friction-reducing Materials are lined, for example, with a Flourpolymeren such as polyfluoroethylene, for example one with a polyfluoroethylene coated eccentric screw pump.

The Thermoplastic matrix can also work in different ways be introduced into the process space, with the choice of dosing according to the form in which the matrix is added. Prefers be for the mixture M2) used pumps which are suitable for materials of higher viscosity, like gear pumps or worm pumps.

there are the mixture M1) and the matrix, preferably as a mixture M2), the process space preferably at different temperatures fed. The lead temperatures follow the others Process conditions. For example, the feed temperature from M1) from 15 to 120 ° C, preferably from 30 to 95 ° C, and more preferably from 40 to 85 ° C. At temperatures, the above the boiling point of M1), the addition usually takes place under overpressure. The feed temperatures from M2) - the example a preferred mixture M2) of SAN copolymer and ethylbenzene, Styrene and acrylonitrile - at Temperatures from 100 to 280 ° C, preferably from 120 to 260 ° C and more preferably from 140 to 240 ° C.

In an embodiment it may be useful, the mixtures M1) and M2) immediately before to premix the entry into the process room and then together in the process space and in the latter then according to the invention the mixture from T and K simultaneous removal of process water and volatile To produce ingredients. To the mixing devices used for manufacturing of the premix are static mixers. there both turbulence mixers and laminarmischer come into consideration. In the turbulence mixers come both free turbulence generating Mixed systems as well as those with internals into consideration. Both Laminar mixers are usually those with more than 4, e.g. 4 to 50 Installed used. Suitable static mixers include Multiflux mixers, Spiral mixer, vortex mixer, lattice mixer, Sulzer SMX mixer, Sulzer SMV mixers and Kenics mixer.

Prefers be the mixture M1) and the thermoplastic matrix, or in particular the mixture M2), introduced separately into the process space.

According to the invention, M1) is mixed with the thermoplastic matrix, which is preferably used in the form of a mixture M2), with evaporation of process water and removal of further volatile constituents in a process space. Volatile constituents are understood above all to be the abovementioned solvents which originate from the mixture M2). For this purpose, a variety of devices are in principle conceivable, as long as this ensures the mixing of the two components while simultaneously removing process water and volatile components in a process space. It is possible to use more than one of these devices, eg two or three devices connected in series for this process. Preferably, however, only one device is used for this process. Particular preference is given to using a large-volume kneading reactor as the device for this process. According to the invention, "large volume" means that not more than 10 kg / h per liter of process volume of products to be degassed M1) and T or M2) are supplied to the process volume DE 197 13 039 A1 in principle also used according to the invention.

The kneader reactors preferred according to the invention have one or more metering orifices, which are generally in the first third of the kneading reactor, based on the total length of the kneading reactor. In this case, M1) and the matrix, preferably in the form of M2) can be fed to the kneading reactor at the same point the, or at different points of the kneading reactor. The dosage may preferably be from top, side or bottom. It is also possible to split the feed streams and metering at several points, wherein the different metering points can be arranged axially apart from one another, or else be arranged in the same position radially on an imaginary circular line around the reactor at a specific position with respect to the shaft pair can. An arrangement of the metering points on an imaginary helix along the axial course of the shaft pair is also possible. Furthermore, a splitting of the metering into different temperature zones of the kneading reactor can take place.

In As a rule, the kneading reactors have one or more, usually horizontal arranged waves, the two-shaft design is preferred is. In the case of multi-shaft design, the waves can be in the same direction or in opposite directions move each other. You can work at the same rotational speed, or each of the waves can be independent from each other or in a certain relationship to each other's own Have rotational speed. The wave or waves are with Kneading and / or mixing elements, preferably equipped with kneading and mixing elements. The kneading or Mixing elements can depending on the embodiment Purify each other more or less completely, so that it constantly to a surface renewal and thus good material exchange comes.

Of the Energy input for Evaporation of process water and volatile components necessary is generally done by heating the apparatus walls, the Shafts and / or the kneading and / or mixing elements. Another share the energy is introduced by the components to be mixed, another by the drive power of the waves. Especially preferred have the apparatus wall of the kneading reactor and / or its kneading and / or Mixing elements several heating zones, the different temperatures are. This creates different temperature zones. Especially Preferably, the apparatus walls the kneading reactor on several different temperature controlled heating zones. For example, you can two or three different heating zones may be present. The temperature For example, in the entry area, where both M1) and the matrix or preferably M2) are still easily flowable, be lower than in the discharge area, where essentially only high-viscosity melt is present. The temperature profile depends on the used Materials and the content of process water to be evaporated or volatile Ingredients. So she can e.g. in the entry area from 120 to 280 ° C, in the middle range from 150 to 300 ° C and in the discharge area from 180 to 320 ° C be.

Usually the kneading reactors are under atmospheric pressure, under slight overpressure or operated by applying a vacuum. Preferred modes of operation are normal pressure or a slight negative pressure, e.g. 0.9 to 0.1 bar. In principle, however, the negative pressure may also be lower, since the inventive method also higher Vapor velocities tolerated. The most preferred pressure range depends on the material and procedural conditions of the individual product such as temperature, solids content of the mixture M1) and M2) or throughput.

According to one preferred embodiment become the mixture M1) with the mixture M2) in contact intensively mixed, whereby process water and other volatile constituents evaporate. Usually the evaporation starts already with entry of M1 or M2) in the process room and even before mixing. During the Material flow through the kneading reactor evaporates the process water as well as the volatile ones Ingredients.

The Degassing can over one, preferably over two or more vents respectively. In general, the number, arrangement and Design of the degassing according to the amount of gas that should leave the kneading reactor. For example For example, the kneading reactor may comprise two or three degassing ports. But it is also possible, that the kneading reactor much more, for example, up to 30, vent openings having. The degassing openings can positioned as desired at the top of the housing of the kneading reactor be. You can but also have a lateral arrangement. Furthermore, a combination the said arrangements come into consideration. There is no powder flight occurs, the vent can for example, nearby the metering opening of M1), the matrix T or M2). Preferably at least a degassing opening in the first half the distance between the entrance side and the exit side face of the kneading reactor.

As degassing, for example, circular holes or holes in the form of a horizontal eight (ie, two directly adjacent circular holes) are suitable. Another preferred embodiment of the degassing openings is rectangular, square or oval. If more than one vent is used, it is also possible that their geometries are different. The vent openings may be provided with domes to control the gas velocity at the exit point of the Keep gas as low as possible and possibly prevent product discharge. It is also possible to clean the degassing through so-called stuffing screws. According to one of the preferred embodiments, the vent is equipped with a metal wire mesh panel ("MVP"), a fine perforated sheet or a slit aperture, among which the MVP is particularly preferred, and if the kneader reactor has more than one vent, at least one of them is preferably equipped. In one of the preferred embodiments, all of the vent openings are equipped in this manner, In another preferred embodiment, some vent openings are so equipped and the remaining vent openings are either open or provided with other devices which prevent product from escaping The MVP, the pinhole plate or the slot orifice is preferably adapted in its geometry to that of the degassing opening The MVP, the fine perforated plate or the slot-type aperture can be fastened in the degassing opening in a very wide variety of ways nnten devices welded into a stable frame, soldered or pressed.

The MVP may comprise a wire mesh, e.g. is smooth or linen weave having. It is possible, that the wire mesh has square mesh or body weave having. But it can also be smooth or smooth tissue Linen binding, a body tassel or Panzertresse act. Mechanically very stable and therefore preferred are multi-layer wire meshes of two or three or more, for example, up to 30 layers, preferably 2 to 10 layers. Prefers are MVP, which is a coarsely woven, large-meshed but mechanically stable backing (Support fabric) and building on that, they are becoming more and more meshed and finely woven Have intermediate and filter layers. For most applications is it prefers that the finest tissue be on the product facing Page is located. The mesh sizes for this finest fabric, for example of 1 μm up to 500 μm be. In general, the mesh sizes of the carrier layer are clearly above and can to several millimeters. The weave can be used for all layers be equal. But it is also possible that the weave for some layers is the same and then changes or changes from location to location Location changes. Weave and the number of layers depend on the respective Task, in particular according to the required mechanical strength, the pressure conditions or the separation task. To increase the me chanical strength of the MVP, the individual wire mesh to be sintered together. This embodiment is preferred.

The can be used according to the invention Fine hole diaphragms are finely perforated sheets with holes of, for example 0.06 to 4 mm. You can also be combined with a wire mesh of the type indicated above, the fine hole plate generally as a carrier material and the wire mesh serves as a filter material. Conversely, it is also possible coarse wire mesh as a carrier and to use a very finely perforated sheet as a filter layer.

Slit diaphragms, used in the invention can be have slot-shaped running openings on. The openings can be uniform in size. Your size can but also vary. The aspect ratio of longer or shorter Axis of the openings may for example be in the range of 60: 1 to 2: 1, preferably 50: 1 to 4: 1. The shorter one the axes of the openings can e.g. from 0.05 to 0.1 mm, preferably 0.05 to 0.09 mm long. The shorter one the axes of the openings can also be longer with multi-layer slot hole apertures, for example until to 0.5 mm long.

The Materials from which MVP, Feinlochblende or Schlitzlochblende are manufactured, depend on the application. Usually these are galvanized or tinned unalloyed steels, NiC (carbon) steels, Cr steels, stainless steels steels like martensitic or austenitic steels of the material groups 1.43 (CrNi steels) or 1.44 (CrNiMo steels). But there are also highly heat-resistant steels into consideration and such made of copper, nickel, titanium or aluminum alloys. Also are metallic surfaces conceivable, which have the so-called lotus effect. For exceptional cases in the low temperature range can also plastics are used. Most applications can use The material groups 1.40 to 1.45 are covered, among which chromium-nickel-molybdenum steels most often be used.

in the Generally, after removing the process water and the essentially of volatiles liberated molding compound as a melt. As a rule, the proportion is on residues including water not more than 800 ppm, preferably not more than 600 ppm based on the melt.

In the kneading reactor can Additives in the for these means usual Quantities are added. The addition of additives preferably takes place in an area where already most of the volatile substances is removed. For example, the addition of the additives takes place in the last third between the entrance side and the exit side face of the kneading reactor.

additives are, for example, waxes, plasticizers, lubricants and mold release agents, Pigments, dyes, matting agents, flame retardants, antioxidants, Stabilizers against exposure to light and thermal damage, fibrous and powdery Filling and reinforcing agents and antistatic agents. The additives can be solid, liquid or pure gaseous present, or already as a mixture of pure substances with each other be used. You can also be used in a formulation which the dosage relieved, perhaps as a solution, or as a dispersion (emulsion or suspension). Also a formulation as Masterbatch, i. as a concentrated mixture with one with the melt acceptable thermoplastic polymers is suitable and in some cases preferred.

In this step can Of course also added other thermoplastic polymers or elastomers become. According to one of the preferred embodiments, the melt only additives added.

The Melt is subsequently discharged. It can either be the same in a formative unit, e.g. an extrusion unit, for example, pipes, profiles or films are processed or, as is preferred, comminuted, For example, be granulated, in principle, all common granulation possible are, such as strand granulation, water ring granulation or underwater granulation. The optional addition of additives and possibly further polymers or elastomers can also be used directly after the discharge of the melt from the process room in different Mixing done. Preference is given to static mixers of various embodiments. Thereafter, it may be supplied to the above molding units.

The Plant for implementation the method according to the invention may be reactors for the preparation of the rubbers in emulsion and such for preparing the matrix and the mixture M2). Alternatively, you can they comprise devices by means of which they are otherwise manufactured Rubbers in emulsion and / or the matrix otherwise prepared or mixture M2) is supplied can be. Furthermore, the plant includes, in addition to those described above for the implementation of inventive method necessary devices suitable for material handling like gear pumps. However, material transport can also be gravimetric respectively. For the discharge of the melt from the process space are generally Discharge screws (single or twin-screw extruder) or gear pumps used. In addition, the system can of course devices for recycling and optional for refurbishing process water removed from the process and more fleeting ones Components include.

By Variation of the mass fraction of M1 introduced into the process space) and T or M2) can be different Products with different toughness and flow ability getting produced. The mixing ratio of T to K may be e.g. without significant changes the process parameters or the device configuration used in the process vary in the range of 10: 1 to 1: 1.

Thereby, that the shear- and temperature-sensitive rubbers are gentle be introduced in the form of a fluid in the process space and the Contact with a hot Matrix melt can be cooled by the evaporating water, the stands out inventive method in that the resulting molding compositions have a low Have their own color. Thereby, that no phase transition due to drainage or coagulation takes place, are also no large agglomerates before, so that the obtainable by the process according to the invention Molding compounds are characterized by the fact that the rubber is very good distributed in the matrix and have a low intrinsic color. The process according to the invention available Molding compounds usually contain T to K in a weight ratio in the Range from 10: 1 to 1: 1. The method according to the invention available Molding compounds are suitable for the production of moldings, films, Fibers or foams.

An example of the inventive method is in the 1 and 2 shown schematically.

Claims (10)

A process for the preparation of molding compositions containing a thermoplastic matrix (T) and a rubber (K) dispersed therein by mixing K, prepared in emulsion in step A), with T while evaporating process water and removing other organic volatiles simultaneously in a process space, characterized in that the emulsion prepared in K after the preparation step A) without prior dewatering in the form of a solids-containing fluid (mixture M1) in the Pro is introduced. Method according to claim 1, characterized in that the M1 by means of a promotion solids-containing fluids suitable pump introduced into the process space becomes. Process according to claims 1 to 2, characterized that T in mixture with an organic solvent (mixture M2) in the process space is introduced. Process according to claims 1 to 3, characterized that M1 has a solids content of 30 to 70 wt .-%. Process according to claims 1 to 4, characterized that M2 has a solids content of 50 to 90 wt .-%. Process according to claims 1 to 5, characterized that the process is in a large volume Kneading reactor performed becomes. Method according to Claim 6, characterized the kneading reactor has at least two degassing openings. Process according to claims 6 to 7, characterized that the kneading reactor has at least one degassing opening, which in the first half the distance between the entrance side and the exit side face the kneading reactor is located. Process according to claims 6 to 8, characterized that the kneading reactor has at least one degassing opening, which with a Metal wire mesh composite panel, a fine perforated sheet or a Slot hole aperture equipped is. Process according to claims 6 to 9, characterized that the apparatus wall of the kneading reactor and / or its mixing elements have several heating zones with different temperature.