DE10134992B4 - Process for the preparation of polyacetal composites with high rigidity and improved barrier properties - Google Patents

Abstract

Process for the preparation of polyacetal composites, wherein phyllosilicate is added in water, there swells, sheared in a further process step and thereby delaminated, water-containing solvent, polyacetal and optionally further additives are added, the mixture with heating in a closed vessel at a pressure of 10 ⁶ to 4 · 10 ⁶ Pa (10 to 40 bar) is dissolved, the polyacetal is precipitated together with at least part of the phyllosilicate and the precipitated product is kneaded in the melt after further treatment.

Description

The The present invention relates to a process for the preparation of Polyacetal composites with high rigidity and improved barrier properties, the material containing polyacetal and phyllosilicate.

method for the preparation of various composites are known. In the preparation of of polyamide-based composites, the layered silicate is replaced by the Monomer swelled, causing a layer widening and delamination leads, and subsequently polymerized.

In another method, the layered silicate is organically modified by exchanging the cations between the layers for, for example, quaternary ammonium ions such as dimethyl-distearylammonium chloride. This is described, for example, in Vaia, Teukolsky, Giannelis, Chem. Mater. 1994, Vol. 6, no. 7, 1017-1022. As a result, the compatibility with plastics is improved, so that in some cases can be produced by compounding the desired composites. In the patent application WO 01/05879 For example, an organically modified phyllosilicate is swollen with a polymerizable monomer, mixed with a polyolefin and a peroxide, and kneaded above the melting temperature of the polyolefin.

Composite comprising polyacetal, layered silicates and additives are from the previously published publications WO 00/69957 A1 . WO 95/14733 A1 . JP 2000351887 A and JP 11130933 A known.

adversely in the aforementioned methods, however, that the layered silicate for this purpose must be subjected to a pretreatment and polyacetal composites after not accessible to this procedure are.

The The object of the present invention is a method to provide for polyacetal based composites, wherein the phyllosilicate is not subjected to pretreatment got to.

These Task is solved by a process for producing polyacetal composites, wherein the phyllosilicate is given in water, there swells, in another Sheared step and thereby delaminated, hydrous Solvent, Polyacetal and optionally further additives are added, the mixture under heating solved is the polyacetal together with at least a portion of the layered silicate precipitated and the failed product after further processing in the melt kneaded and optionally with other additives is mixed.

The layered silicate which is used in the process according to the invention generally contains magnesium silicate or aluminum silicate. Examples of useful phyllosilicates are montmorillonite, bentonite, saponite, beidellite, hectorite, nontronite, volkonskoite, pyroysite, sauconite, magadiite, keniaite and stevensite. Further examples are vermiculite and muscovite, phlogopite, biotite, lepidolite, paragonite, tetrasilicit. Advantageously used are the sodium forms of said layered silicates, in particular sodium montmorillonite and sodium bentonite. The phyllosilicates which can be used according to the invention have an ion exchange capacity of at least 50 milliequivalents per 100 grams of phyllosilicate, advantageously 50 to 150 milliequivalents per 100 grams of phyllosilicate. The ion exchange capacity can be determined by the ammonium acetate method or the methylene blue method, which are well known to those skilled in the art. Particularly advantageous
Montmorillonite, [Al _4-x Mg _x Si ₈ O ₂₀ (OH) _4-f F _f ] x R ⁺ , where 0.55 <= x <= 1.1, f <= 4 and R is selected from one or more of the ions Na, Li, ammonium;
Bentonite, [Al _4-x Mg _x (Si _8-y Al _y ) O ₂₀ (OH) _4-f F _f ] (x + y) R ⁺ , where 0 <= x <= 1.1, 0 <= y < = 1.1, 0.55 <= (x + y) <= 1.1, f <= 4 and R is selected from one or more of the ions Na, Li, ammonium;
Hectorite, [Mg _6-x Li _x Si ₈ O ₂₀ (OH) _4-f F _f ] x R ⁺ , where 0.57 <= x <= 1.15, f <= 4 and R is selected from one or more of the ions Na, Li, ammonium;
Saponite, [Mg _6-y Al _y Si _8-sy Al _{x + y} O ₂₀ (OH) _4-f F _f ] x R ⁺ , where 0.58 <= x <= 1.18, 0 <= y <= 0.66, f < = 4 and R is selected from one or more of the ions Na, Li, ammonium;
Stevensite, [Mg _6- xSi ₈ O ₂₀ (OH) _4- fF _f ] 2xR ⁺ , where 0.28 <= x <= 0.57, f = 4 and R is selected from one or more of the ions Na, Li, ammonium ;
Beidellite, [Al _{4 + y} (Si _8-xy Al _{8 + y} ) O ₂₀ ) _4-f F _f ] xR ⁺ , where 0.55 <= x <= 1.1, 0 <= y <= 0.44, f <= 4 and R is selected from one or more of the ions Na, Li, ammonium.

Particularly preferred are montmorillonite and bentonite. Very particular preference is given to sodium montmorillonite and sodium bentonite, which are obtainable, for example, as EXM 757 from Süd-Chemie or as cloisite Na ⁺ from Southern Clay. In the method according to the invention, the layered silicate in What swollen and then sheared. The shearing can be carried out with stirring units suitable for this purpose, in particular with high-speed stirrers such as an Ultra-Turrax. This results in a delamination of the layer structure of the phyllosilicate used.

Then be hydrous solvent, Polyacetal and optionally further additives added.

The hydrous solvents contains Water and water-miscible solvents, such as Methanol, trioxane, dioxolane, methylal. From the manufacturing process of the polyacetal Also, other compounds may be present, such as formic acid, formaldehyde and / or cyclic and / or linear low molecular weight homologs (= Oligomers) of the polyacetal.

Especially preferred is methanol. The weight ratio of water to methanol is in the resulting mixture advantageously 3: 1 to 1: 9. The advantageous one Water content is dependent from the temperature, to the later is to be heated and is advantageously at most 50 wt .-%, in particular 15-30 Wt .-%. At a temperature of 170 ° C, a water content of 15 Wt .-% preferably, at a temperature of 190 ° C, a water content of 25% by weight is preferred. The phyllosilicate is advantageous in one Amount of 1 to 15 wt .-%, based on the total amount of polyacetal and phyllosilicate used. Preference is given to 2 to 14.9 wt .-%. The weight ratio of polyacetal to phyllosilicate is particularly advantageous in the range of 49: 1 to 9: 1.

Regarding the other additives are not particularly limited necessary. It can in principle all known compounds are used which enhance the stability of the polyacetal not overly impair. As further additives can be advantageous phase mediator use.

When Phase mediators can be used are water-soluble polymers, ammonium salts and amines. As water-soluble Polymers can For example, polyethylene glycol, polydioxolane, Polypropylene glycol, polytetrahydrofuran, polyvinyl alcohol, polyvinyl methyl ether, Polyvinylpyrrolidone, singly or as a mixture.

When Phase mediators usable amines and ammonium salts are in principle all of these compounds that are soluble in the mixture.

wobei R₁, R₂, R₃ und R₄ gleich oder unterschiedlich sind und eine Gruppe enthalten, die ausgewählt ist aus a) linearen oder verzweigten aliphatischen, Aralkyl- oder aromatischen Kohlenwasserstoffresten oder Fluorkohlenwasserstoffresten oder anderen Halogenkohlenwasserstoffresten mit 1 bis 30 Kohlenstoffatomen; b) Alkyl- oder Alkylestergruppen mit 2 bis 30 Kohlenstoffatomen; c) alkoxylierte Gruppen enthaltend 1 bis 80 Kohlenstoffatome; d) Amidgruppen; e) Oxazolidingruppen; f) Allyl-, Vinyl-, oder andere Alkenyl- oder Alkinylgruppen enthaltend reaktive Mehrfachbindungen; e) Wasserstoff;
und wobei X^– ein Anion enthält, welches ausgewählt ist aus der Gruppe bestehend aus Chlorid, Iodid, Bromid, Methylsulfat, vorzugsweise Chlorid. Ebenfalls einsetzbar sind quartäre Phosphonium- und Sulfoniumsalze, die analog zu den oben beschriebenen Ammoniumsalzen definiert sind.Ammonium salts which can be used as phase mediators are, in particular, quaternary ammonium salts of the general formula

wherein R ₁ , R ₂ , R ₃ and R _{4 are the} same or different and contain a group selected from a) linear or branched aliphatic, aralkyl or aromatic hydrocarbon radicals or fluorocarbon radicals or other halohydrocarbon radicals having 1 to 30 carbon atoms; b) alkyl or alkylester groups of 2 to 30 carbon atoms; c) alkoxylated groups containing 1 to 80 carbon atoms; d) amide groups; e) oxazolidine groups; f) allyl, vinyl, or other alkenyl or alkynyl groups containing reactive multiple bonds; e) hydrogen;
and wherein X ^- contains an anion selected from the group consisting of chloride, iodide, bromide, methylsulfate, preferably chloride. Also usable are quaternary phosphonium and sulfonium salts, which are defined analogously to the ammonium salts described above.

Examples of groups which can be used as R ₁ to R ₄ are:
saturated linear and branched alkyl groups such as methyl, methoxy, ethyl, ethoxy, hydroxyethyl, propyl, butyl, dodecyl, hexadecyl, 12-methylstearyl, 12-ethylstearyl;
aromatic groups such as benzyl and substituted benzyl groups such as groups derived from benzyl halides, benzhydryl halides, trityl halides, α-halo-α-phenylalkyl wherein the alkyl chain contains from 1 to 30 carbon atoms such as 1-halo-1-phenyloctadecane; substituted benzyl groups such as ortho-meta and para-chlorobenzyl halides, para-methoxybenzyl halides, ortho-meta and para-nitrilobenzyl halides and ortho-meta and para-alkylbenzyl halides, wherein the alkyl chain contains from 1 to 30 carbon atoms;
condensed aromatic radicals which are derived, for example, from 2-halomethylnaphthalene, 9-Halomethylanthracen and 9-Halomethylphenenthren, wherein as the halogen group chlorine, bromine or any other group is used, which acts as a leaving group in a nucleophilic attack, so that the nucleophile, the leaving group replaced at the aromatic residue. Examples of other aromatic groups include phenyl and substituted phenyl groups, N-alkyl and N, N-dialkylanilines wherein the alkyl groups contain from 1 to 30 carbon atoms; ortho-meta and para-nitrophenyl, ortho-meta and para-alkylphenyl wherein the alkyl group contains from 1 to 30 carbon atoms; 2-, 3- and 4-halophenyl, wherein the halogen group is defined as chlorine, bromine, iodine, and 2-, 3-, and 4-carboxyphenyl and their esters, wherein the alcohol component of the ester is derived from an alkyl alcohol whose alkyl group is 1 contains up to 30 carbon atoms, in particular ethyl, methyl, propyl, butyl, or is derived from phenol or an aralkyl alcohol such as benzyl alcohol; condensed aromatic-derived groups such as naphthyl, anthracenyl and phenanthrenyl. Examples of particularly preferred ammonium salts are triethylammonium chloride, tributylammonium chloride, dimethylbehenylammonium chloride, trimethyldodecylammonium chloride, trimethyloctadecylammonium chloride, trimethylhexadecylammonium chloride, trimethylhexadecylammonium bromide.

wobei R₁, R₂ und R₃ gleich oder unterschiedlich sind und R₁ bis R₃ analog zu den oben beschriebenen Resten R₁ bis R₄ definiert sind. Besonders bevorzugte Amine sind Triethylamin, Tributylamin, Tridodecylamin, Tris-[(2-methoxyethoxy)-ethyl] amin, N,N-Dimethyldodecylamin, N,N-Dimethylhexadecylamin.Amines which can be used as phase mediators are, in particular, amines of the general formula

wherein R ₁ , R ₂ and R _{3 are the} same or different and R ₁ to R _{3 are defined} analogously to the above-described radicals R ₁ to R ₄ . Particularly preferred amines are triethylamine, tributylamine, tridodecylamine, tris - [(2-methoxyethoxy) ethyl] amine, N, N-dimethyldodecylamine, N, N-dimethylhexadecylamine.

Of the Phase mediator is inventively in an amount of 30% 220% of the ion exchange capacity of the layered silicate used, advantageously in an amount of 40% to 200% of the ion exchange capacity of the phyllosilicate, especially advantageously in an amount of 85% to 115%, in particular about 100%.

When Polyacetals can in the method according to the invention Polyoxymethylene homopolymers or copolymers are used. homopolymers of the formaldehyde or trioxane are those polymers whose hydroxyl end groups are chemically stabilized against degradation in a known manner, for. B. by esterification or etherification. Copolymers are polymers Formaldehyde or its cyclic oligomers, in particular trioxane, and cyclic ethers, cyclic acetals and / or linear polyacetals. In the method according to the invention In particular, the so-called crude polymer can also be used become. This is the reaction product of cationic polymerization of trioxane and one or more comonomers using of known initiators and optionally molecular weight regulators. This crude polymer contains unreacted monomers and unstable end groups such as Example hemiacetal and formate groups used in the subsequent procedure degraded and / or for the production of polyacetal composites the whereabouts are removed in the hydrolysis liquor.

POM homopolymers or copolymers are known per se to the person skilled in the art and are described in the literature. In general, these polymers have at least 50 mole percent of recurring units -CH ₂ O- in the polymer backbone. The homopolymers are generally prepared by polymerization of formaldehyde or trioxane, preferably in the presence of suitable catalysts. Examples of suitable catalysts are boron trifluoride and trifluoromethanesulfonic acid.

enthalten, wobei R¹ bis R⁴ unabhängig voneinander ein Wasserstoffatom, eine C₁- bis C₄-Alkylgruppe oder eine halogensubstituierte Alkylgruppe mit 1 bis 4 C-Atomen und R⁵ eine -CH₂-, -CH₂O-, eine C₁- bis C₄-Alkyl- oder C₁- bis C₄-Haloalkyl substituierte Methylengruppe oder eine entsprechende Oxymethylengruppe darstellen und n einen Wert im Bereich von 0 bis 3 hat. Vorteilhafterweise können diese Gruppen durch Ringöffnung von cyclischen Ethern in die Copolymere eingeführt werden. Bevorzugte cyclische Ether sind solche der Formel

wobei R¹ bis R⁵ und n die obengenannte Bedeutung haben. Nur beispielsweise seien Ethylenoxid, 1,2-Propylenoxid, 1,2-Butylenoxid, 1,3-Butylenoxid, 1,3-Dioxan, 1,3-Dioxolan und 1,3-Dioxepan als cyclische Ether sowie lineare Oligo- oder Polyformale wie Polydioxolan oder Polydioxepan als Comonomere genannt.In the context of the invention, preference is given to POM copolymers, in particular those which, in addition to the repeating units -CH ₂ O-, also contain up to 50, preferably from 0.1 to 20 and in particular from 0.5 to 10, mol% of recurring units

wherein R ¹ to R ^{4 are} independently a hydrogen atom, a C ₁ - to C ₄ alkyl group or a halogen-substituted alkyl group having 1 to 4 carbon atoms and R ^{5 is} a -CH ₂ -, -CH ₂ O-, a C ₁ to C ₄ alkyl or C ₁ to C ₄ haloalkyl substituted methylene group or a corresponding oxymethylene group and n has a value in the range of 0 to 3. Advantageously, these groups can be introduced into the copolymers by ring opening of cyclic ethers. Preferred cyclic ethers are those of the formula

wherein R ¹ to R ⁵ and n have the abovementioned meaning. For example, ethylene oxide, 1,2-propylene oxide, 1,2-butylene oxide, 1,3-butylene oxide, 1,3-dioxane, 1,3-dioxolane and 1,3-dioxepane as cyclic ethers and linear oligo- or polyformals such as Polydioxolane or polydioxepan called comonomers.

Especially advantageous are copolymers of 99.5-95 mol% trioxane and 0.5 to 5 mol% of one of the aforementioned comonomers.

wobei Z eine chemische Bindung, -O- oder -ORO- (R=C₁- bis C₈-Alkylen oder C₂- bis C₈-Cycloalkylen) ist, hergestellt werden.Likewise suitable are oxymethylene terpolymers which are obtained, for example, by reacting trioxane, one of the cyclic ethers described above, and with a third monomer, preferably a bifunctional compound of the formula

wherein Z is a chemical bond, -O- or -ORO- (R = C ₁ - to C ₈ -alkylene or C ₂ - to C ₈ -cycloalkylene) can be prepared.

preferred Monomers of this type are ethylene diglycidyl, diglycidyl ether and diether from glycidylene and formaldehyde, dioxane or trioxane in the molar ratio 2: 1 and diether from 2 mol glycidyl compound and 1 mol of an aliphatic Diols with 2 to 8 carbon atoms such as the diglycidyl ethers of ethylene glycol, 1,4-butanediol, 1,3-butanediol, cyclobutane-1,3-diol, 1,2-propanediol and cyclohexane-1,4-diol, to name just a few examples to call.

method for the preparation of the above-described POM homopolymers and copolymers are known in the art and described in the literature.

The preferred POM copolymers have melting points of at least 150 ° C and weight average molecular weights M _w in the range of from 5,000 to 200,000, preferably from 7,000 to 150,000. End-group stabilized POM polymers having C-C bonds at the chain ends. are particularly preferred. The POM used polymers have from 2 to 50 cm ^3/10 min, in general, a melt index (MVR value 190 / 2.16) (ISO 1133).

The mixture prepared from delaminated sheet silicate, aqueous solvent, polyacetal and optionally further additives and / or phase mediator is dissolved with heating. For this purpose, the mixture is heated to 150 ° C to 200 ° C, advantageously 170 ° C to 190 ° C. The heating takes place in a closed vessel to prevent the evaporation of the solvent. The pressure in the closed vessel is generally 10 ⁶ to 4 x 10 ⁶ Pa (10 to 40 bar), preferably 1.5 x 10 ⁶ to 3 x 10 ⁶ Pa (15 to 30 bar), in particular 1.9 x 10 ⁶ to 2.9 x 10 ⁶ Pa (19 to 29 bar). While the pressure is not critical to the process, it is necessary to prevent boiling of the existing solvents.

To This process step, the product is precipitated. That can fail in principle, by all known methods, for example by cooling the solution, by incorporation in a solvent or solvent mixture or by adding a precipitant. The failure is advantageous by Cooling causes, either actively cooling or the solution Cooling allowed to the ambient temperature. In this case, the polyacetal coincides with at least a portion of the layered silicate. The amount of together with the polyacetal precipitated sheet silicate is usually 2% to 100%, advantageously 20% to 80% of the amount of the used Sheet silicate.

The precipitated product is then subjected to further processing. In general, the filtration of the product and subsequent drying is sufficient as further treatment. However, the product may optionally be subjected to a different and / or further treatment. The solid product may, for example, also be decanted or centrifuged and / or washed. The drying can be effected, for example, by heating, if appropriate in a gas stream, irradiation, application of a vacuum, freeze-drying or a combination of these and / or other processes. The methods and devices used for further processing are well known to those skilled in the art. The separation of the solid product from the liquid phase can also be achieved in an advantageous embodiment of the invention by sedimentation. The particular advantage of this method is that this method is particularly suitable for continuous operation and the product is also washed during this process. For this purpose, in particular the devices and methods are suitable, which in the published patent applications DE 19847428 . DE 19847435 . DE 19915705 and DE 19912269 to be discribed.

The Product is kneaded in the melt after further processing and optionally mixed with other additives. The kneading in the melt can in principle in the mixing units known for this purpose carried out become. Advantageously, static mixers are particularly advantageous Extruder, in particular equipped with a device for granulation Extruder. The product can during kneading in the melt, but also before or after kneading mixed with other additives or otherwise provided become. As additional additives can be used processing aids, Colorants, fillers, gain and / or polymeric lubricants; Examples include, for example, formaldehyde scavengers, acid scavengers, antioxidants, UV stabilizers, adhesion promoters, nucleating agents and mold release agents or carbon fibers, aramid fibers, glass fibers, impact modifiers such as polyurethanes and graft copolymer, which is a product of a Graft reaction of an olefin polymer and an acrylonitrile / styrene copolymer is, glass beads, calcium carbonate, wollastonite, silica and additional Lubricants and their mixtures called, but without the scope to limit to the examples given. Additional lubricants are for For example, ultra-high molecular weight polyethylene (PE-UHMW) and polytetrafluoroethylene (PTFE), polyethylene waxes and oxidized polyethylene waxes, aliphatic Esters such as esters of saturated or unsaturated aliphatic carboxylic acids, in particular ester waxes, stearyl stearate, behenyl behenate, isostearyl stearate, Glycerol monostearate, glycerol monoisostearate, glycerin distearate, Pentaerythritol tetrastearate, pentaerythritol tetrabehenate, montan acid ester, Montansäureester partially hydrolyzed. As a nucleating agent, for example, talc and / or polyoxymethylene terpolymer.

The according to the inventive method producible polyacetal composites have increased rigidity, improved heat resistance and improved barrier properties, d. H. an improved barrier effect against gases and liquids.

Examples

When Polyacetal was a polyacetal copolymer used as a comonomer 5.6 wt .-% dioxolane was used (Hostaform C270xx Ticona GmbH, Kelsterbach). The mixtures were 1 ml of triethylamine and 0.1 g of formic acid as Buffer added.

mechanical exams were performed according to ISO 527.

The Permeation measurements were carried out according to DIN 53 122.

Of the Ash content was reduced by one hour Pyrolysis of the samples at 600 ° C determined in the muffle furnace and weighing.

The Values for the weight loss at 240 ° C (Thermobalance (ks 240)) by heating a sample for 25 to 60 minutes to 240 ° C under nitrogen atmosphere determined on a thermobalance. It will be the weight loss in milligrams received per time. The weight loss is in per hour specified.

The thermal stability (TS) is determined by taking a sample of the material to be examined for 120 minutes in the air at 210 ° C is heated. The thermal stability indicates the weight loss in percent.

Of the MVR is rated to ISO 1133 at a temperature of 190 ° C and a Coating weight of 2.16 kg, unless otherwise stated.

Formaldehyde emission: The composites are used to make slabs of wall thickness 1 mm. After a Storage period of 24 h was the formaldehyde emission from the plates according to VDA 275 (VDA recommendation No. 275, documentation Kraftfahrwesen e. July, 1994).

Test specimen production: The specimen material is molded by injection molding into plates with the dimensions 80 × 50 × 1 mm. An injection molding machine Krauss Maffei KM 120 / 340B is used with the following injection molding parameters:
Melt temperature 195 ° C, flow front velocity 200 mm / s, mold wall temperature 85 ° C, holding pressure 900 bar, holding pressure 30 s, cooling time 10 s, back pressure 0 to 10 bar. The test specimens are stored before the test for 24 h in the standard climate chamber at 23 ° C and 50% relative humidity.

Exam: Two Be test specimen in a 1 liter glass bottle over 50 ml of e-water suspended on a stainless steel hook and for 3 h in a convection oven at 60 ° C stored. The test specimens are from the test bottle away. 5 ml sample solution are pipetted into a test tube, the test tube is for 10 minutes at 95 ° C tempered. Now, 3 ml of acetylacetone and 3 ml of a 20% ammonium acetate solution in added the test tube. The formaldehyde forms with the reagents the diacetyldihydrolutidine complex, its absorption at 412 nm is determined photometrically. The absorption becomes the formaldehyde concentration in the sample solution calculated.

Brabender test: The polyoxymethylene molding compound is sheared at 210 ° C in a Brabender kneader with a twin screw. The escaping formaldehyde is discharged with an inert gas stream and absorbed in a sodium sulfite solution whereby hydroxide ions (OH ^- ) are released. These are titrated continuously with 0.1 N sulfuric acid, thus the liberated formaldehyde is determined quantitatively. As a result, formaldehyde release is obtained as a function of time. From the slope of the curve, the degradation rate is determined by linear extrapolation.

• 1. Herstellen einer 10%igen Bentonit-Stammlösung aus Bentonit EXM 757 durch Dispergierung mit einem Ultra-Turrax im Wasser (→ Delaminierung des Schichtsilikats).
• 2. Vormischen der Einsatzstoffe, wobei beim Wasser der Anteil durch die Bentonit-Stammlösung berücksichtigt wurde.
• 3. Einfüllen der Mischung in den Autoklav.
• 4. Aufheizen des Autoklaven unter Rühren auf die gewünschte Innentemperatur (ca. 40–50 min).
• 5. Ablesen des maximal erreichten Innendrucks (siehe Tabelle 1).
• 6. Abkühlen des Hydrolyseansatzes unter Rühren auf Raumtemperatur (ca. 2–2,5 h).
• 7. Absaugen der Suspension über einen Filter und Nachwaschen mit Methanol.
• 8. Trocknen des Rückstandes im Trockenschrank.

Tabelle 1: Rezepturen und Versuchsbedingungen zur ersten Versuchsreihe. Ansatz-Nr. T_End [°C] p_max* [bar] POM^# [g] Bentonit [g] Wasser [g] Methanol [g] Beispiel 1 170 19,6 49 1,0 150 800 Beispiel 2 190 27,9 49 1,0 150 800 Beispiel 3 170 19,7 45 5,0 150 800 Beispiel 4 190 28,8 98 2,0 150 750 Beispiel 5 170 19,5 90 10 150 750 Beispiel 6 190 28,7 90 10 150 750 Beispiel 7 170 18,9 49 1,0 250 700 Beispiel 8 170 17,9 45 5,0 250 700 Beispiel 9 190 26,8 45 5,0 250 700 Beispiel 10 170 17,8 98 2,0 250 650 Beispiel 11 190 26,3 98 2,0 250 650 Beispiel 12 190 26,1 90 10 250 650 Beispiel 13 170 18,4 70,5 4,5 200 725 Beispiel 14 190 27,4 70,5 4,5 200 725 Beispiel 15 180 22,3 73,5 1,5 200 725 Beispiel 16 180 22,7 67,5 7,5 200 725 Beispiel 17 180 22,7 47 3,0 200 750 Beispiel 18 180 22,4 94 6,0 200 700 Beispiel 19 180 23,6 70,5 4,5 150 775 Beispiel 20 180 21,8 70,5 4,5 250 675 Beispiel 21 180 22,6 70,5 4,5 200 725 Beispiel 22 180 22,2 70,5 4,5 200 725 The experiments were carried out as follows:

• 1. Preparation of a 10% bentonite stock solution of bentonite EXM 757 by dispersing with an Ultra-Turrax in water (→ delamination of the sheet silicate).
• 2. premixing the starting materials, wherein the proportion of water was taken into account by the bentonite stock solution.
• 3. Fill the mixture into the autoclave.
• 4. Heating of the autoclave with stirring to the desired internal temperature (about 40-50 min).
• 5. Reading the maximum achieved internal pressure (see Table 1).
• 6. Cool the hydrolysis batch with stirring to room temperature (about 2-2.5 h).
• 7. Aspirate the suspension through a filter and rinse with methanol.
• 8. Dry the residue in a drying oven.

Table 1: Formulations and experimental conditions for the first series of experiments. Approach no. T _End [° C] p _max * [bar] POM ^# [g] Bentonite [g] Water [g] Methanol [g] example 1 170 19.6 49 1.0 150 800 Example 2 190 27.9 49 1.0 150 800 Example 3 170 19.7 45 5.0 150 800 Example 4 190 28.8 98 2.0 150 750 Example 5 170 19.5 90 10 150 750 Example 6 190 28.7 90 10 150 750 Example 7 170 18.9 49 1.0 250 700 Example 8 170 17.9 45 5.0 250 700 Example 9 190 26.8 45 5.0 250 700 Example 10 170 17.8 98 2.0 250 650 Example 11 190 26.3 98 2.0 250 650 Example 12 190 26.1 90 10 250 650 Example 13 170 18.4 70.5 4.5 200 725 Example 14 190 27.4 70.5 4.5 200 725 Example 15 180 22.3 73.5 1.5 200 725 Example 16 180 22.7 67.5 7.5 200 725 Example 17 180 22.7 47 3.0 200 750 Example 18 180 22.4 94 6.0 200 700 Example 19 180 23.6 70.5 4.5 150 775 Example 20 180 21.8 70.5 4.5 250 675 Example 21 180 22.6 70.5 4.5 200 725 Example 22 180 22.2 70.5 4.5 200 725

The resulting products were then analyzed to determine the MVR (190 / 2.16) and ash content (ashing at 600 ° C). The results are summarized in Table 2. Table 2: Analysis results for the first series of experiments. Approach no. MVR [ml / 10 min] Bentonite _used [%] Ash content [%] example 1 21.3 2 0.17 Example 2 24.4 2 0.01 Example 3 18.4 10 3.27 Example 4 25.4 2 0.54 Example 5 13.7 10 5.53 Example 6 20.3 10 0.8 Example 7 21.0 2 0.09 Example 8 24.4 10 0.48 Example 9 (42.7) 10 0.72 Example 10 19.3 2 0.74 Example 11 27.8 2 0.48 Example 12 18.7 10 0.89 Example 13 18.1 6 0.25 Example 14 21.0 6 0.29 Example 15 23.0 2 0.31 Example 16 18.4 6 0.49 Example 17 19.0 6 0.09 Example 18 19.3 6 0.33 Example 19 20.6 6 0.28 Example 20 17.8 6 0.43 Example 21 19.3 6 0.35 Example 22 19.0 6 0.31

Of the strongly varying ash content indicates that an essential Part of the phyllosilicate in solution remains and does not precipitate along with the polyacetal.

In Further experiments were the resulting products after drying compounded. After cooling with stirring the products were over sucked a suction filter, washed with methanol and then dried.

To Comparative Example 2 (without bentonite) 9.6% Bentonite EXM 757 was added during compounding. Furthermore, as Comparative Example 1, the pure starting material was also compounded with the stabilizer package. Table 3: Formulations and experimental conditions. approach T _End [° C] p _max [bar] POM [g] (%) Bentonite [g] (%) HCOOH [g] Water [g] (%) TEA [ml] Methanol [kg] (l) Comparative Example 2 170 20.1 3000 (7.6) 0 4 5000 (12,6) 50 31.6 (40) Example 23 170 20.6 3000 (7.5) 333 (0.83) 9 5000 (12.5) 50 31.6 (40) Example 24 170 28.8 3000 (7.4) 335 (0.83) 0 5500 (13.6) 50 31.6 (40)

• * POM/Schichtsilikat-Komposit (siehe Tabelle 3); ** Aschegehalt siehe Tabelle 5.

The products obtained in this way were stabilized by means of a Leistritz laboratory extruder compounded. The stabilizer package used consisted of: 0.50% polyacetal terpolymer; 0.40% Irganox 245; 0.20% Licowax C; 0.20% melamine and 0.10% eurelon. The formulations of the compounding tests are summarized in Table 4. Table 4: Formulations and experimental conditions of the compounding experiments. approach Speed [rpm] T _Heating1 [° C] T _heating2-6 [° C] T _nozzle [° C] "POM" amount Bentonite EXM 757 stabilizer package Comparative Example 1 100 180 190 190 2465 g - 35 g Comparative Example 2 100 180 190 190 2225 g 240 g 35 g Example 23 100 180 190 190 2465 * g ** 35 g Example 24 100 180 190 190 2465 * g ** 35 g

• * POM / phyllosilicate composite (see Table 3); ** Ash content see table 5.

The granules obtained were characterized by determining the MVR and the ash content. The data are summarized in Table 5. Table 5: Analysis data of the compounds. approach colour MVR [ml / 10 min] Ash [%] ks 240 [% / h] TS [%] Comparative Example 1 White 24.4 0 0.214 2.5 Comparative example 2 green 20.3 8.94 2,855 10.65 Example 23 cream 23.4 0.70 0,150 1.9 Example 24 cream 22.1 1.37 0.473 2.5

By Determination of thermal stability and investigations on a thermobalance (ks 240) could be found be that the A compounding of bentonite (Comparative Example 2) the thermal Stability of the Material severely impaired. In contrast, the compounds in which bentonite on the Hydrolysis was introduced (Examples 23 and 24) a good thermal stability and a slight color deviation.

permeation

• * bei 23°C und 53% rel. Feuchte; ** bei 23°C und 85% rel. Feuchte

For the permeation measurements, 1 mm thick plates (15 × 15 cm) were used, which were used to examine the permeation. The results of the permeation measurements (oxygen and water vapor) are shown in Table 6. Table 6: Data of permeation measurements. Approach / plates Thickness [μm] O ₂ permeability [ml / m ² * dbar] * H ₂ O permeability [g / m ² .d] ** Example 23 997 ± 40 1.74 to 1.75 1.36 Example 24 1010 ± 30 1.71 to 1.73 1.30 to 1.31 Comparative Example 1 900 ± 45 2.51 to 2.66 1.62-1.71

• * at 23 ° C and 53% rel. humidity; ** at 23 ° C and 85% rel. humidity

The Oxygen permeability is about 30% in examples 23 and 24, the water vapor permeability compared to nearly 20% reduced to Comparative Example 2.

Examples using phase mediators

• 1. Herstellen einer 10%igen Bentonit-Stammlösung aus Bentonit EXM 757 (Südchemie) bzw. Cloisite Na+ (Southern Clay) durch Dispergierung mit einem Ultra-Turrax im Wasser.
• 2. Einfüllen der Einsatzstoffe in einen Autoklaven (80 l Kessel):zuerst 40 l Methanol, dann das restliche Wasser (5,5 l abzüglich der Menge zum Ansetzen der Bentonit-Stammlösung), 3,0 kg POM-Pulver, die Bentonit-Stammlösung, Phasenvermittler (gegebenenfalls als wäßrige Lösung).
• 3. Aufheizen des Autoklaven unter Rühren auf die Endtemperatur von 170°C (Dauer ca. 40 min).
• 4. Abkühlen des Ansatzes unter Rühren auf Raumtemperatur (ca. 3,5 h).
• 5. Abdrücken der Suspension auf einen Filter, Absaugen und Nachwaschen mit 2 × 30 l Wasser und 40 l Methanol.
• 6. Trocknen des Rückstandes bei 70°C im Vakuum.

The experiments were carried out as follows:

• 1. Preparation of a 10% bentonite stock solution from Bentonite EXM 757 (South Chemistry) or Cloisite Na + (Southern Clay) by dispersing with an Ultra-Turrax in water.
• 2. Filling the feeds into an autoclave (80 l kettle): first 40 l of methanol, then the remaining water (5.5 l minus the amount for preparing the bentonite stock solution), 3.0 kg of POM powder, the bentonite Stock solution, phase mediator (if appropriate as aqueous solution).
• 3. Heating the autoclave with stirring to the final temperature of 170 ° C (duration about 40 min).
• 4. Cool the mixture with stirring to room temperature (about 3.5 h).
• 5. Press the suspension onto a filter, suction and rinse with 2 × 30 l of water and 40 l of methanol.
• 6. Dry the residue at 70 ° C in vacuo.

In Trying in a pilot plant autoclave was tested as the addition of various organic compounds to the ash content (= Content of phyllosilicate) of the powder after hydrolysis. The formulations are summarized in Table 7.

• * Bentonit EXM 757 (Südchemie); ** Cloisite Na+ (Southern Clay).

Table 7: Recipes of the test series. approach POM [kg] Bentonite [g] Water [kg] Methanol [l] HCOOH [g] (ml) Name of phase mediator (abbreviation) Amount of PV [g] / (ml) Comparative Example 3 3.0 0 5.5 40 10 (8,2) Triethylamine (TEA) 40.6 (56) Example 25 3.0 333 * 5.5 40 10 (8,2) Triethylamine (TEA) 40.6 (56) Example 26 3.0 333 * 5.5 40 10 (8,2) Tributylamine (TBA) 74 (95) Example 27 3.0 333 * 5.5 40 10 (8,2) Tridodecylamine (TDA) 208 (250) Example 28 3.0 333 * 5.5 40 10 (8,2) Triethanolamine (TEtOHA) 60 (53) Example 29 3.0 333 * 5.5 40 0 Polyethylene glycol PEG 600 44 (40) Example 30 3.0 333 * 5.5 40 0 Polyethylene glycol PEG 600 88 (80) Example 31 3.0 333 * 5.5 40 0 Polyethylene glycol PEG 200 88 (80) Example 32 3.0 333 * 5.5 40 10 (8,2) Tridodecylamine (TDA) 208 (250) Comparative Example 4 3.0 0 5.5 40 10 (8,2) Triethylamine (TEA) 40.6 (56) Example 33 3.0 333 * 5.5 40 0 - 0 Example 34 3.0 500 * 5.5 40 0 - 0 Example 35 3.0 333 * 5.5 40 0 Triethylamine (TEA) 40.6 (56) Example 36 3.0 500 * 5.5 40 0 Triethylamine (TEA) 61 (84) Example 37 3.0 333 * 5.5 40 0 Polyethylene glycol PEG 6000 50 Example 38 3.0 500 * 5.5 40 0 Polyethylene glycol PEG 6000 75 Example 39 3.0 333 * 5.5 40 0 Polydioxolane (PDO) 50 Example 40 3.0 500 * 5.5 40 0 Polydioxolane (PDO) 50 Example 41 3.0 333 * 5.5 40 0 Tris - [(2-methoxyethoxy) ethyl] amine (MeOEtOEt) ₃ N 100 Example 42 3.0 500 * 5.5 40 0 N, N-dimethyldodecylamine (Me ₂ C ₁₂ N) 107 (138) Example 43 3.0 500 * 5.5 40 0 Trimethyldodecylammonium chloride (Me ₃ C ₁₂ N ⁺ Cl ^- ) 132 Example 44 3.0 333 * 5.5 40 0 N, N-dimethylhexadecylamine (Me ₂ C ₁₆ N) 80 (100) Example 45 3.0 333 * 5.5 40 0 Trimethylhexadecylammonium bromide (Me ₃ C ₁₆ N ⁺ Br ^- ) 100 Example 46 3.0 333 ** 5.5 40 0 Trimethylhexadecylammonium bromide (Me ₃ C ₁₆ N ⁺ Br ^- ) 100 Example 47 3.0 333 ** 5.5 40 0 Trimethylhexadecylammonium bromide (Me ₃ C ₁₆ N ⁺ Br ^- ) 120 Example 48 3.0 333 ** 5.5 40 0 Trimethylhexadecylammonium chloride (Me ₃ C ₁₆ N ⁺ Cl ^- ) 85 Example 49 3.0 333 ** 5.5 40 0 Trimethylhexadecylammonium chloride (Me ₃ C ₁₆ N ⁺ Cl ^- ) 105 Example 50 3.0 333 ** 5.5 40 0 Trimethyloctadecylammonium chloride (Me ₃ C ₁₈ N ⁺ Cl ^- ) 93 Example 51 3.0 333 ** 5.5 40 0 Trimethyloctadecylammonium chloride (Me ₃ C ₁₈ N ⁺ Cl ^- ) 115 Comparative Example 5 3.0 0 5.5 40 10 (8,2) Triethylamine (TEA) 40.6 (56)

• * Bentonite EXM 757 (South Chemistry); ** Cloisite Na + (Southern Clay).

The products obtained were analyzed to determine the MVR (190 / 2.16), the ash content (ashing at 600 ° C) and the degradation in the thermobalance (240 ° C under nitrogen). The results are summarized in Table 8. Table 8: Analysis results. approach phase mediator MVR [ml / 10 min] Bentonite _used [%] Ash content [%] Comparative Example 3 TEA 34.1 0 - Example 25 TEA 33.2 10 0.71 Example 26 TBA 26.0 10 0.57 Example 27 TDA 70.3 10 1.90 Example 28 TetOHA 29.9 10 0.58 Example 29 PEG 600 24.4 10 0.50 Example 30 PEG 600 24.4 10 0.31 Example 31 PEG 200 26.6 10 0.52 Example 32 TDA nb 10 0.88 Comparative Example 4 TEA nb 0 - Example 33 - 22.5 10 0.28 Example 34 - 26.0 14.3 0.33 Example 35 TEA 22.1 10 0.69 Example 36 TEA 18.1 14.3 0.91 Example 37 PEG 6000 23.9 10 0.68 Example 38 PEG 6000 24.9 14.3 1.24 Example 39 PDO 26.6 10 0.27 Example 40 PDO 23.9 14.3 0.45 Example 41 (MeOEtOEt) ₃ N 24.4 10 0.95 Example 42 Me ₂ C ₁₂ N 24.9 14.3 0.54 Example 43 Me ₃ C ₁₂ N ⁺ Cl ^- 20.3 14.3 1.07 Example 44 Me ₂ C ₁₆ N 25.4 10 0.69 Example 45 Me ₃ C ₁₆ N ⁺ Br ^- 19.9 10 4.90 Example 46 Me ₃ C ₁₆ N ⁺ Br ^- - 10 4.38 Example 47 Me ₃ C ₁₆ N ⁺ Br ^- - 10 2.04 Example 48 Me ₃ C ₁₆ N ⁺ Cl ^- - 10 2.18 Example 49 Me ₃ C ₁₆ N ⁺ Cl ^- - 10 2.21 Example 50 Me ₃ C ₁₈ N ⁺ Cl ^- - 10 4.21 Example 51 Me ₃ C ₁₈ N ⁺ Cl ^- - 10 2.30 Comparative Example 5 TEA - 0 -

Of the varying ash content indicates that part of the phyllosilicate in solution remains and does not precipitate along with the polyacetal. The highest Levels of phyllosilicate were increased by the addition of quaternary ammonium salts to the hydrolysis approaches achieved.

The powder obtained in the manner described above (composites) were over for stabilization compounded a Leistritz laboratory extruder. The used stabilizer package consisted of: 0.50% terpolymer; 0.30% Irganox 245; 0.20% Licowax C; 0.05% melamine; 0.05% Eurelon and in some cases * (see Table 9) 0.10% Calcium citrate.

The formulations of the compounding tests are summarized in Table 9. Table 9: Formulations and experimental conditions of the compounding experiments. approach Speed [rpm] T _Heating1 [° C] T _heating2-6 [° C] T _nozzle [° C] Quantity [g] Bentonite [g] / (%) Stabilizer package [g] Comparative Example 3 100 180 190 190 2967 0 33 Example 25 100 180 190 190 2967 33 Example 26 100 180 190 190 2967 33 Example 27 100 180 190 190 2967 33 Example 28 100 180 190 190 2967 33 Example 29 100 180 190 190 2967 33 Example 30 100 180 190 190 2967 33 Example 31 100 180 190 190 2967 33 Example 32 70 160 170-180 180 2967 33 Comparative Example 4 100 180 190 190 2964 36 * Example 33 100 180 190 190 2964 36 * Example 34 100 180 190 190 2964 36 * Example 35 100 180 190 190 2967 33 Example 36 100 180 190 190 2967 33 Example 37 100 180 190 190 2964 36 * Example 38 100 180 190 190 2964 36 * Example 39 100 180 190 190 2964 36 * Example 40 100 180 190 190 2964 36 * Example 41 100 180 190 190 2967 33 Example 42 100 180 190 190 2967 33 Example 43 100 180 190 190 2967 33 Example 44 100 180 190 190 2967 33 Example 45 100 180 190 190 2967 33 Comparative Example 6 100 180 190 190 2904 60 (2) 36 * Comparative Example 5 100 180 190 190 2814 150 (5) 36 * Example 46 100 180 190 190 2967 33 Example 47 100 180 190 190 2967 33 Example 48 100 180 190 190 2967 33 Example 49 100 180 190 190 2967 33 Example 50 100 180 190 190 2967 33 Example 51 100 180 190 190 2967 33

In In the comparative examples bentonite was used in the polymer used mixed. In Comparative Example 6, the starting polymer was used.

The granules obtained were characterized (MVR, ash content, thermobalance ks 240 and thermal stability TS) and, for the determination of the mechanical properties, tensile specimens were injected by some compounds. The data are summarized in Table 10. Table 10: Analysis data of the compounds. approach Brabender degradation [ppm / h] MVR [ml / 10 min] ks 240 [% / h] TS [%] Ash content [%] VDA 275 [ppm] Breaking stress [MPa] Elongation at break [%] Modulus of elasticity [MPa] Comparative Example 3 175 34.1 0.131 4.3 0 19.6 55.5 ± 3.5 17.4 ± 4.4 2790 ± 35 Example 25 1360 24.4 4.4 15.3 0.62 144 57.3 ± 2.7 15.3 ± 4.3 2784 ± 53 Example 26 432 25.4 0.62 5.6 0.34 66 56.7 ± 1.7 17.1 ± 2.7 2793 ± 40 Example 27 nb 36.2 nb nb 1.18 nb nb nb nb Example 28 344 29.9 0.44 4.4 0.57 64 54.6 ± 2.3 17.9 ± 2.0 2839 ± 38 Example 29 390 23.9 0.76 6.7 0.54 96 54.2 ± 2.5 19.5 ± 3.4 2820 ± 60 Example 30 124 24.4 0,155 2.9 0.38 42 55.5 ± 3.1 17.6 ± 5.8 2858 ± 68 Example 31 1500 24.4 7.51 23.3 0.52 286 53.7 ± 1.8 19.8 ± 1.6 2842 ± 21 Example 32 > 2300 37.3 35.0 76.5 0.97 nb 55.4 ± 2.7 15.1 ± 3.2 2897 ± 54 Comparative Example 4 51 30.6 0.173 1.8 0 7.0 nb nb nb Example 33 208 21.9 1.46 4.4 0.29 45 nb nb nb Example 34 626 21.7 17.2 15.1 0.39 85 nb nb nb Example 35 > 2300 20.3 60.3 57.2 0.67 56 nb nb nb Example 36 > 2300 18.4 59.2 62.3 0.75 117 nb nb nb Example 37 265 22.5 0.677 3.9 0.83 228 nb nb nb Example 38 1493 22.5 4.29 11.1 1.29 92 nb nb nb Example 39 442 22.1 7.13 14.2 0.33 48 nb nb nb Example 40 430 21.7 11.4 10.8 0.51 57 nb nb nb Example 41 > 2300 23.4 37.0 15.8 1.02 165 nb nb nb Example 42 > 2300 23.0 23.5 90.7 0.68 205 nb nb nb Example 43 1494 21.0 7.0 16.3 1.40 31 nb nb nb Example 44 > 2300 24.9 100 98.7 0.92 311 nb nb nb Example 45 > 2300 19.9 69.2 86.0 5.09 289 nb nb nb Comparative Example 6 > 2300 27.8 66.7 32.7 1.80 290 nb nb nb Comparative Example 5 nb 46.0 21.0 42.3 4.47 nb 56.6 ± 0.8 5.7 ± 0.8 3229 ± 8 Example 46 nb 24.4 31.0 68.7 4.70 nb 53.1 ± 0.6 4.1 ± 0.35 3741 ± 14 Example 47 nb 21.3 18.2 55.0 2.18 nb 57.7 ± 0.8 7.3 ± 0.6 3403 ± 12 Example 48 nb 21.3 17.6 41.8 2.75 nb 59.0 ± 0.7 5.7 ± 0.4 3471 ± 13 Example 49 nb 19.9 13.8 39.1 2.56 nb 57.6 ± 0.6 6.9 ± 0.45 3502 ± 12 Example 50 nb 19.6 26.3 70.0 4.28 nb 53.6 ± 1.0 3.75 ± 0.5 3701 ± 11 Example 51 nb 20.3 14.3 28.0 2.52 nb 57.2 ± 0.9 7.5 ± 1.25 3471 ± 10

The Analytical values show that the thermal stability of (TS and ks 240) is adversely affected by the addition of layered silicates. At low phyllosilicate concentration (≤ 0.8%) and certain phase mediators (tributylamine, triethanolamine, PEG 600 and PEG 6000), TS and ks 240 values were measured in the usual Frame lie.

at the mechanical values, in particular of the samples with an ash content from> 2 to about 5% the train modulus 20-30% higher than with unmodified Hostaform. Also compared to a compound from POM with about 4.5% phyllosilicate without phase mediator is the stiffness increased by about 10%.

• * bei 23°C und 53% rel. Feuchte; ** bei 23°C und 85% rel. Feuchte.

Of selected compounds, 1 mm thick plates were sprayed (approximately 15 x 15 cm) used to study permeation. The permeation measurements (oxygen and water vapor) are shown in Table 11. Table 11: Data of permeation measurements. Approach / plates phase mediator Thickness [μm] O ₂ permeability [ml / m ² * dbar] * H ₂ O permeability [g / m ² .d] ** Remarks / color of the plates Comparative Example 4 without 1070 ± 35 1.65 ± 0.07 1.43 ± 0.03 without phyllosilicate / white Example 38 PEG 6000 1080 ± 30 1.50 ± 0.0 1.37 ± 0.03 about 1.25% bentonite / cream Example 42 (MeOEtOEt) ₃ N 1080 ± 30 1.65 ± 0.07 1.455 ± 0.01 about 0.7% bentonite / cream Example 45 Me ₃ C ₁₆ N ⁺ Br ^- 1085 ± 25 0.90 ± 0.07 0.90 ± 0.03 about 5% bentonite / beige Comparative Example 6 without 1085 ± 30 1.65 ± 0.07 1.40 ± 0.01 about 2% bentonite / cream Comparative Example 5 without 1130 ± 20 1.80 ± 0.01 1.47 ± 0.0 about 5% Cloisite Na ⁺ / greenish beige with specks Example 46 Me ₃ C ₁₆ N ⁺ Br ^- 1105 ± 25 1.00 ± 0.07 0.81 ± 0.0 about 4.5% Cloisite Na ⁺ / beige Example 50 Me ₃ C ₁₈ N ⁺ Cl ^- 1118 ± 25 0.89 ± 0.04 0.81 ± 0.01 about 4.5% Cloisite Na ⁺ / beige

• * at 23 ° C and 53% rel. humidity; ** at 23 ° C and 85% rel. Humidity.

The Values in Table 11 show about 45% lower oxygen permeability and also about 45% lower water vapor permeability in Examples 45, 46 and 50 compared to the Comparative Examples and examples with a lower content of phyllosilicate.

Claims (13)

Process for the preparation of polyacetal composites, wherein phyllosilicate is added in water, there swells, sheared in a further process step and thereby delaminated, water-containing solvent, polyacetal and optionally further additives are added, the mixture dissolved under heating in a closed vessel at a pressure of 10 ⁶ to 4 · 10 ⁶ Pa (10 to 40 bar) is, the polyacetal is precipitated together with at least a portion of the layered silicate and the precipitated product is kneaded after further treatment in the melt. The method of claim 1, wherein the hydrous solvent contains one or more of the following substances: methanol, trioxane, dioxolane, Methylal, formic acid, Formaldehyde, cyclic and / or linear homologues of the polyacetal. The method of claim 1 or 2, wherein as further Additive at least one phase mediator is used. The method of claim 3, wherein as a phase mediator one or more of the following substances are used: amines, quaternary Ammonium salts, water-soluble Polymers, polyethylene glycol, polydioxolane triethylamine, tributylamine, Tridodecylamine, tris - [(2-methoxyethoxy) ethyl] amine, N, N-dimethyldodecylamine, trimethyldodecylammonium chloride, N, N-dimethylhexadecylamine, Trimethyloctadecylammonium chloride, trimethylhexadecylammonium chloride, Trimethyihexadecylammoniumbromid be used. Method according to one or more of claims 1 to 4, wherein by cooling or introduction into a solvent mixture precipitated becomes. Method according to one or more of claims 1 to 5, wherein as layer silicate montmorillonite, bentonite, hectorite, Saponite, stevensite or beidellite is used. Method according to one or more of claims 1 to 6, wherein the mixture of polyacetal, phyllosilicate and hydrous solvent the weight ratio of water to methanol is between 3: 1 to 1: 9. Method according to one or more of claims 1 to 7, wherein in the mixture of polyacetal, phyllosilicate and hydrous solvent the weight ratio of polyacetal to phyllosilicate is between 49: 1 and 9: 1. Method according to one or more of claims 1 to 8, wherein the mixture of polyacetal, layered silicate, hydrous solvent and optionally further additives have a water content of at the most 25 wt .-%, advantageously at most 15% by weight. Method according to one or more of claims 1 to 9, wherein the layered silicate in an amount of 1 to 15 wt .-%, based on the sum of the weights of polyacetal and phyllosilicate, is included. Method according to one or more of claims 1 to 10, wherein phase mediator in an amount of 30% to 220% of the ion exchange capacity of the layered silicate is used. Method according to one or more of claims 1 to 11, wherein the ion exchange capacity of the phyllosilicate greater than 50 milliequivalents per 100 g, advantageously 50 to 150 milliequivalents per gram. Method according to one or more of claims 1 to 12, wherein the mixture is heated to 150 to 200 ° C, advantageously 170 ° C to 190 ° C.