DE102011056693A1 - Mold for the production of plastic foam parts with hybrid polymer coating to improve demolding - Google Patents

Abstract

The present invention relates to a mold for curing elastomers, in particular of polyurethane polymers, characterized by a coating applied on the inside of the mold of or comprising a silicic acid (hetero) polycondensate in which hydrocarbon groups bonded via carbon atoms to silicon atoms are present, with the following provisos: (i) In addition to silicon, the condensate may contain 2-, 3- or tetravalent metal atoms which are exclusively bound to the condensate network via oxygen atoms and may have hydroxy-, alkoxy- or oxygen-bonded complex ligands but no metal -Kohlenstoffbindungen. (ii) A proportion of silicon atoms corresponding to at least 20% of the sum of all silicon and metal atoms has groups bonded via carbon atoms. (iii) Not more than 10% of all silicon atoms carry more than 2 carbon-bonded groups. (iv) 20-100 mol% of the carbon-bonded groups are selected from one or more alkyl, aryl, arylalkyl and alkylaryl groups (A) whose carbon chain, if it has at least 3 carbon atoms, may be interrupted by oxygen atoms can. Furthermore, it relates to their preparation and use and a specific silicic acid (hetero) polycondensate, which is suitable for the production of the coating of the mold.

Description

The invention relates to a tool with a coating with pronounced non-stick effect, which is suitable as a permanent release agent for the demolding of elastomeric plastics, in particular soft polyurethane foam parts.

In the modern production of plastic parts separating tools are used to separate products from tools, which must be reapplied after each bar or a few bars in order to achieve optimum performance. Without these separation aids, some processes would be inconceivable, or the waste or damaged parts would be too high to be economically viable. Affected are procedures such. As injection molding, powder-slush process or foaming processes. The setup processes and cleaning of molds are time-consuming and expensive in the plastics processing industry. A longer service life of the molds due to permanently acting, stable separating layers with the same product quality increases the efficiency.

In the production of acoustically effective automotive interior linings, which are backfoamed with a polyurethane (PUR) soft foam, a reactive PUR monomer mixture is injected into a tempered aluminum mold, where the foaming process begins. After curing of the PUR material, the soft foam part is manually removed from the mold. In this process, a sprayable mold release agent is usually used, the application of which leads to a significant particle load of the room air and partly critical solvent emissions.

The production of shaped skins for automobile cockpit modules takes place eg via powder slush method. In this case, PVC or TPU powder (TPU is a thermoplastic PUR elastomer) is melted on the surface of a heated metallic mold with a galvanically deposited nickel surface (a so-called Ni-Galvanos). After a subsequent gelation phase, the mold is cooled and the instrument panel skin can be removed. Finely structured tools are used for the production of such molded skins, which are operated in the temperature range 50-280 ° C. Alternatively, the powder-sintering process can be combined with a light-stable, emission-reducing coating (IMC slush process). The IMC slush process enables the production of finished decorative skins in one process step. First of all, the mold cavity mold cavity is painted, heated and then connected to a box with TPU powder. As this unit rotates, a portion of the powder on the lacquer layer gels to a skin. After cooling down and removing the powder box, the lacquered skin can be removed. Compared to polyurethane spray technology and pure slush molding, multicolored decorative skins can be made easier and more economical by simply laminating them in the mold (Bayer MaterialScience press release:
http://www.atzonline.de/Aktuell/Nachrichten/1/6531/Neuer-TPU-Werkstoff-fuer-Dekorhaeutekaelteflexibelkomma-weichmacher--und-halogenfrei.html ). For this process, so-called semi-permanent release agents are currently used, which allow a certain number of separation cycles before they have to be renewed.

• • Einfache Applikation
• • Hohe Temperaturbeständigkeit
• • Hohe Trennwirkung zur leichten Entformbarkeit der Haut / des Schaums
• • Gute Haftung an der Metallform mit hoher Beständigkeit gegen mechanische Beschädigungen
• • Geringe Gleitreibung
• • Erzielung der gewünschten Optik (Glanzgrad, Farbort), Haptik oder Zelligkeit
• • Falls das Äquivalent der Anzahl erreichbarer Zyklen geringer ist als die Lebensdauer der Form, kommt die einfache Reinigung der Form als weiteres Kriterium hinzu.

In addition to the highest possible number of process cycles, which is ideally equivalent to the life of the mold, an ideal release agent must meet in particular the following criteria:

• • Simple application
• • High temperature resistance
• • High release effect for easy removability of the skin / foam
• • Good adhesion to the metal mold with high resistance to mechanical damage
• • Low sliding friction
• • Achieving the desired look (gloss, color), feel or cell
• • If the equivalent of the number of achievable cycles is less than the life of the mold, the simple cleaning of the mold adds another criterion.

Various release agent systems are currently used for PUR demoulding. External release agents (water- or solvent-based) currently represent the most frequently used system. The release agents consist of release-active substances, eg. As waxes or silicones, suspended, dissolved or emulsified in water or solvents as a carrier medium. Aqueous systems are increasingly preferred due to environmental legislation, especially in areas where high mold temperatures occur (eg, hot foam production). In cases where the use of aqueous systems causes problems, pure hydrocarbons (HC) can be used as release agents (eg cold foam), which is, however, viewed critically in many countries due to the VOC problem. Internal release agents are separation-active Additives in the material to be molded. Due to the usually required high volume concentrations (to generate a release effect on the surface), the properties of the molding can unfavorably change, which is a major disadvantage. On the other hand, the use of internal release agents leads to the elimination of release agent application time and thus to a significant increase in productivity.

The application of a semi-permanent release agent allows several mold releases before the mold surface has to be aftertreated or recoated, thus reducing the release agent application time and thus increasing the cost-effectiveness. Here are mainly silicone or silicone resin-like materials are used, which may contain polymerizable and dissolved or suspended, polymerized components. After a cross-linking reaction, a more or less closed layer is formed on the mold surface, from which several molds can be removed from the mold. Applicant's microscopic investigations have shown that such layers are irreparably damaged after only a few demolding cycles and show progressive adhesions. When 3 SEM images of non-colored Ni platelets coated with a commercial semi-permanent release agent and subjected to the IMC-slush process are added. Left: situation after 10th demoulding; right: situation after 25th demoulding. Clearly visible are a breakout (left) and an adhesion of IMC lacquer material to such an eruption.

On closer inspection, the Teflon coatings, which are referred to as permanent release agents, prove to be only semi-permanent, since they also show stratigraphies with increasing number of cycles and have to be renewed cost-intensive, which also jeopardizes their economic viability. Also due to their poor wettability, e.g. in the IMC process, they are of limited use. Mixed methods, such. For example, the combined use of semi-permanent and liquid release agents to extend the service life of the coating, however, can be an economic option for PUR-processing processes, but are expensive.

It was therefore the task of developing a tool coating with pronounced non-stick effect, which makes the use of such non-permanent or semi-permanent release agent ideally completely unnecessary or at least reduced to a minimum. With quantities per year and tooling of up to 60,000, the durability requirements of the coating are very high - depending on the cost of applying and replacing the coating, it should be able to withstand between a few hundred and a few thousand cycles. In addition, a certain hardness and abrasion resistance and good sliding action are required so that the layer is not damaged by the removal of the molding or by inserted in the tools reinforcing or functional elements. The tool surface is often metallic in nature, for example, it is a tool made of aluminum or with an aluminum or nickel surface on its side facing the molding to be formed side.

The problem is solved by the proposal to equip the tool inner surface with a coating consisting of a silicic acid (hetero) polycondensate or this has as a matrix. The silicic acid (hetero) polycondensate has a non-polar basic structure as well as chemical groups which impart hydrophobic, preferably oleophobic properties to the material and has a low surface energy of preferably <20-25 mN / m.

Silica (hetero) polycondensates are known in large numbers. These are inorganic-organic (hybrid) nanocomposites, also referred to as (hetero) poly (organo) siloxanes, which consist of organo (alkoxy) silanes, main or subgroup metal alkoxides and other components, for example via the known sol-gel Process (hydrolysis and polycondensation of metal alkoxides) have become important chemical nanotechnology products in recent decades. The attractive features of these nanoscale composite materials are ideally high transparency (glassy), processability at moderate temperatures or by UV irradiation (polymer-like), good thermal stability and low surface energy (silicon-like) and wide availability of the starting compounds (see G. Schottner, K. Rose, S. Amberg-Schwab, Kunststoffe 94 (2004) 306 and 4 ). Such multifunctional layers can be obtained starting from functional building blocks in multicomponent systems via colloidal intermediates. However, due to the almost unlimited combination possibilities it is not trivial to find customized condensates for specific applications.

• (i) Das Kondensat kann neben Silicium 2-, 3- oder vierwertige Metallatome enthalten, die ausschließlich über Sauerstoffatome in das Kondensat-Netzwerk eingebunden sind und ggf. Hydroxy-, Alkoxy- oder sauerstoffgebundene Komplexliganden aufweisen, aber keine Metall-Kohlenstoffbindungen.
• (ii) Ein Anteil von Siliciumatomen, der mindestens 20 % der Summe aller Silicium- und Metallatome entspricht, weist über Kohlenstoffatome gebundene Gruppen auf.
• (iii) Höchstens 10 %, häufig 0 bis höchstens 3 % aller Siliciumatome tragen mehr als 2 über Kohlenstoffatome gebundene Gruppen. Vorzugsweise sind es höchstens 10 % derjenigen Siliciumatome, die mindestens eine über Kohlenstoff gebundene Gruppe aufweisen.
• (iv) 20–100 Mol-%, vorzugsweise 50 bis 100 Mol-% und besonders bevorzugt annähernd 100% der über Kohlenstoff an Silicium gebundenen Gruppen sind ausgewählt unter gleichen oder unterschiedlichen Alkyl-, Aryl-, Arylalkyl- und Alkylarylgruppen (A), deren Kohlenstoffkette, wenn sie mindestens 3 Kohlenstoffatome aufweist, ggf. durch Sauerstoffatome unterbrochen sein kann.
• (v) Bei einem Teil der Si-C-gebundenen Gruppen kann es sich um verbrückende Gruppen handeln, z.B. Alkylengruppen, deren Kohlenstoffkette ggf. durch Heteroatome oder Gruppen wie -C(O)-, -C(O)O-, -CO(NH)-, -NHC(O) oder -NHC(O)NH- sowie deren Thioanaloge unterbrochen sein kann.
• (vi) Bis zu 30 Mol-% der Alkyl-, Aryl-, Arylalkyl- und Alkylarylgruppen (A) können ganz oder teilweise fluoriert sein.

The said basic structure as well as the hydrophobic / oleophobic properties of the silicic acid (hetero) polycondensate according to the invention is obtained by the presence of hydrocarbon groups bonded via carbon atoms to silicon atoms, in particular alkyl or phenyl groups, with the following provisos:

• (i) In addition to silicon, the condensate may contain 2-, 3- or tetravalent metal atoms that are exclusively bound to the condensate network via oxygen atoms and may have hydroxy-, alkoxy- or oxygen-bonded complex ligands, but no metal-carbon bonds.
• (ii) A proportion of silicon atoms corresponding to at least 20% of the sum of all silicon and metal atoms has groups bonded via carbon atoms.
• (iii) Not more than 10%, often 0 to not more than 3% of all silicon atoms have more than 2 groups bonded via carbon atoms. Preferably, at most 10% of those silicon atoms have at least one carbon-bonded group.
• (iv) 20-100 mol%, preferably 50 to 100 mol% and particularly preferably approximately 100% of the groups bonded to silicon via carbon are selected from the same or different alkyl, aryl, arylalkyl and alkylaryl groups (A), whose carbon chain, if it has at least 3 carbon atoms, may optionally be interrupted by oxygen atoms.
• (v) Some of the Si-C bonded groups may be bridging groups, eg, alkylene groups whose carbon chain may be substituted by heteroatoms or groups such as -C (O) -, -C (O) O-, -CO (NH) -, -NHC (O) or -NHC (O) NH- and their thio analogues may be interrupted.
• (vi) Up to 30 mol% of the alkyl, aryl, arylalkyl and alkylaryl groups (A) may be wholly or partly fluorinated.

In a first embodiment, at least a portion of said alkyl, aryl, arylalkyl and alkylaryl groups (A) are alkyl groups of at least 4, more preferably of at least 8 to 16 carbon atoms, or phenyl groups. The individual silicon atoms preferably carry only one such group; if groups (A) are phenyl groups, they may instead carry two such groups.

In an alternative embodiment, at least a part of said groups (A) are methyl, ethyl or propyl groups. Of these, methyl groups are preferred. In this embodiment, it is favorable if at least 20% of the silicon atoms contain two such groups. It is particularly preferred if several silicon atoms are linked to two such groups directly via oxygen atoms, so that silicone-like structures of the formula -SiR ₂ -O-SiR ₂ -O-SiR ₂ -O with R is equal to C ₁ -C ₃ - Alkyl or phenyl, preferably at least predominantly methyl arise. It is enough a relatively small proportion of such structures. Thus, in a particularly preferred form of the invention, at least 10% of the silicon atoms are part of a silicone-like structure of the aforementioned type of at least 3, preferably at least 5 more preferably at least 7 and more preferably at least 10 each substituted with two C ₁ -C ₃ alkyl groups silicon atoms. Typically, this silicone-like structure comprises up to 15, more rarely up to 20, of these di-alkyl-substituted silicon atoms. Among these, more preferably 50-100% are substituted with two methyl groups. By this measure, the surface energy of the cured silicic acid (hetero) polycondensate is reduced to ≤20 mN / m. The two aforementioned embodiments can also be combined with each other. The silicic acid (hetero) polycondensate then contains both short-chain alkyl groups and / or phenyl groups and long-chain alkyl groups. Also particularly preferred in this combination is the presence of silicone-like structures, these being composed of only two C ₁ -C ₃ -alkyl- or methyl-substituted silicon atoms or of C ₁ -C ₃ -alkyl- or methyl-substituted silicon atoms and phenyl-substituted twofold Silicon atoms are constructed. It is very particularly preferred if the proportion of C ₁ -C ₃ -alkyl- or methyl-substituted silicon atoms is higher than the proportion of phenyl-substituted silicon atoms.

When fluorine-substituted groups (A) are present, it is preferred that these are partially fluorinated, optionally interrupted by oxygen atoms alkyl groups having at least 4 carbon atoms, preferably having at least 6 carbon atoms and more preferably having at least 16-24 carbon atoms. Based on all groups (A), the proportion of fluorine-substituted groups should preferably not more than 15 mol%, preferably not more than 7 mol%, more preferably not more than 5 mol% and most preferably not more than 3 mol% be. The said upper limit of fluorine-substituted groups is based on the observation of the inventors that too high a proportion of corresponding starting materials may affect their miscibility; it can then come to a phase separation. Of course, environmental reasons always speak in favor of economical use of such materials; not least cost reasons.

The silicic acid (hetero) polycondensate which can be used according to the invention can contain further groups (B) which are bonded to silicon via carbon atoms and which carry polar radicals. Suitable for this purpose are for example primary amino groups, ammonium groups, SH groups, carboxylic acid radicals or activated carboxylic acid radicals such as anhydride radicals substituted hydrocarbon radicals, in particular alkyl radicals. The Ammonium groups can be secondary, tertiary or quaternary ammonium groups. Their nitrogen atom can carry methyl groups and / or longer-chain alkyl, aryl, arylalkyl or alkylaryl groups, for example two short and one long alkyl chain or three short alkyl chains. The carbon chain of the hydrocarbon radicals of the groups (B) may optionally be interrupted, for example by oxygen atoms, sulfur atoms or NH groups. The counterions of the ammonium groups can be arbitrarily selected; For example, it may be chloride or acetate.

The groups (B) are selected depending on the material of the mold; they serve to improve the adhesion of the coating to the tool surface. For example, an alkylamino group (B) is particularly suitable for the production of a coating intended for aluminum. Their content is preferably not more than 20 mol% of the sum of the groups bonded via carbon atoms (A) plus (B), more preferably not more than 10 mol%, and most preferably not more than 6 mol%.

Up to 80% of the silicon atoms of the silicic acid polycondensate may be free of groups bonded via carbon atoms. Some of these silicon atoms - usually up to 50% of them - can be replaced by 2-, 3- or 4-valent metal atoms. Such a condensate is referred to herein as silicic acid heteropolycondensate. A high proportion of such components makes the condensate relatively hard and brittle. However, it has been found that when the condensate has the siloxane structures described above, the proportion of silicon atoms which is free of groups bonded via carbon atoms, or the proportion of other metal atoms, may be relatively low. If, for example, the proportion of silicone-like structures of the formula -SiR ₂ -O-SiR ₂ -O-SiR ₂ -O with R is C ₁ -C ₃ -alkyl or phenyl, preferably at least a majority of methyl, at least 10%, based on the silicon atoms of the condensate, as defined above, the proportion of silicon atoms which is free of groups bonded via carbon atoms or the proportion of other metal atoms can be between 0 and 20%.

In order to obtain a particularly strong and dense coating, which nevertheless is not brittle, a part of the groups bonded via carbon atoms may favorably be selected from groups (C) which have organically polymerisable C =C double bonds or epoxy groups. By polymerizing these groups, the condensate can receive, in addition to the inorganic network, an organic network penetrating therethrough.

The silicic acid (hetero) polycondensate which can be used according to the invention is preferably prepared by hydrolytic condensation of suitable starting materials, preferably by means of the sol-gel technique.

For the incorporation of the groups (A), for example, one or more silanes of the formula (Ia) R _a R ¹ _b SiX _4-ab (Ia) and / or one or more siloxanes of the formula (Ib) (R ³ O) Si (R ⁴ ) ₂ (A) _m Si (R ² ) ₂ [OSi (R ² ) ₂ ] _n (A) _m Si (R ⁴ ) ₂ (OR ³ ) (Ib) wherein
R is selected from unfluorinated, partially fluorinated or fully fluorinated C ₄ -C ₂₄ -alkyl, aryl, alkylaryl and arylalkyl having in each case 6 to 24 carbon atoms, where the carbon skeleton of the alkyl groups may in all cases be interrupted by oxygen atoms,
R ^{1 is} selected from C ₁ -C ₃ -alkyl and in particular methyl,
X is selected from hydrolytically condensable groups, in particular groups OR ¹ , as well as OH,
each radical R ^{2 is} independently selected from other radicals R ² is C ₁ -C ₃ alkyl, aryl, alkylaryl and arylalkyl having in each case 6 to 24 carbon atoms, particularly preferably methyl and phenyl, wherein preferably the two radicals R ² , the are bound to one and the same silicon atom, have the same meaning,
R ^{3 is} selected from hydrogen and C ₁ -C ₃ -alkyl,
R ^{4 has} the meaning of R ¹ or of X as defined above,
A is an alkylene group optionally interrupted by O, S, NR ³ , C (O) O, C (O) NR ³ , NR ³ C (O) or NR ³ C (O) NR ³ , preferably having 4 to 12 carbon atoms,
a is 0 or 1
b is 0, 1 or 2 with the proviso that the sum of a and b is 1 or 2,
m is 0 or 1
n is an integer between 1 and 50, preferably between 1 and 25 and more preferably between 3 and 15,
be used in suitable amounts (ratios) to meet the above conditions, which should meet the silicic acid (hetero) polycondensate,

Examples of non-fluorinated silanes and siloxanes are:

Examples of silanes with fluorinated groups are:

For incorporation of groups (B) silanes of the formula (II) can be used: R ⁵ SiX ' ₃ (II) wherein
R ^{5 is} a hydrocarbon group which is either substituted by at least one group selected from SH, NH ₂ , NR ⁶ ₃ + Z ^- and C (O) OY, substituted or by a group NR ⁶ ₂ ⁺ Z ^- ,
R ^{6 is} selected from hydrogen and C ₁ -C ₂₄ -alkyl,
Y is hydrogen or -C (O) - wherein the carbonyl group is attached to the hydrocarbon group with the free bond (ie C (O) OY is part of an anhydride)
Z ^{- is} a monovalent anion or a corresponding proportion of a polyvalent anion, as well as
X 'is OR ¹ and R ^{1 is} as defined above.

Exemplary silanes are:

The proportion of groups (B) in the inventive silicic acid (hetero) polycondensate is not critical; in general, it is about 5 to 20%, based on the sum of all groups bonded via silicon to carbon, i. based on (A) plus (B) plus (C).

For the proportion of silicon atoms which have no groups bonded via carbon atoms or to corresponding other metal atoms, the following silanes of the formula (III) or metal compounds of the formula (V) can be used: SiX _'4 (III) wherein X 'has the meaning given above for the silanes of the formula (II), and / or M ^{d +} X " _d (V) wherein M is a metal from the group of tri- and tetravalent main group elements and the trivalent or tetravalent transition metal elements, X "has the meaning of X 'or is a C ₄ -C ₆ alkoxide or a monodentate ligand or a tooth of a polyvalent ligand and d is 3 or 4.

Examples are:

For the incorporation of groups (C) are, for example, silanes of the formula (IV) R ⁷ aR ¹ _b SiX _4-ab , (IV), wherein R ¹ and X are as defined for formula (Ia) and R ^{7 is} a radical bonded via a carbon atom to the silicon, which carries at least one C = C double bond or at least one epoxy group. The C = C- Double bond is favorably part of an acrylate or methacrylate group. The index a is usually 1, but may also mean 2 in exceptional cases. The index b is 0 or 1.

Examples are:

The proportion of groups (C) in the inventive silicic acid (hetero) polycondensate is not critical; it is generally at most 50%, preferably 10 to 30%, and most preferably 10 to 20%, based on the sum of all groups bonded via silicon to carbon, i. based on (A) plus (B) plus (C).

In all embodiments of the invention, R ^{1 is} preferably methyl and X 'is preferably methoxy or ethoxy. X "is preferably ethoxy, n- or i-propoxy or n- or s-butoxy.

The present invention can be used in all molding processes for plastic components, including elastomers such as polyolefins, polyesters, copolymers based on these materials, PVC, rubber or rubber, but especially for components made of PUR. It has surprisingly been found that the hybrid polymer coating of the present invention on the one hand well adheres to the (usually metallic) surface of the mold, on the other hand allows the easy detachment of the (organic) elastomer formed in the mold. The easy release of the elastomer is due to a combination of low surface energy with hydrophobic or even oleophobic properties of the coating. Free On the other hand, hydroxy groups remaining after the hydrolytic condensation guarantee good adhesion to the metallic substrate.

The silanes and siloxanes (I) are characterized by having a nonpolar structure. This is a prerequisite for a low surface energy.

In a first preferred embodiment, the silicic acid (hetero) polycondensate is obtained by hydrolytic condensation of exclusively silanes of the formula (Ia) and / or siloxanes of the formula (Ib), if appropriate in combinations with those of the formula (II) in a quantitative ratio of 100 to 60 mol% (I) to 0 to 40 mol% (II).

In a second preferred embodiment, the silicic acid (hetero) polycondensate is obtained by hydrolytic condensation of silanes of the formula (I) (ie (Ia) and / or (Ib)), if appropriate in combinations with those of the formula (II) in a quantitative ratio from 100 to 60 mol% (I) to 0 to 40 mol% (II), and in addition silanes of the formula (III), wherein the ratio of the silanes of the formula (I) plus optionally (II) to the silanes of the formula (III) in the range of 20 to 80 mol% (I) plus optionally (II) to 80 mol% to 20 mol% (III), preferably 60 to 75 mol% (I) plus, if appropriate (II) to 40 to 25 mol% (III). In this embodiment, the silanes of the formula (III) may be partially or completely replaced by metal compounds of the formula (V).

In a third preferred embodiment, the proportion of the sum of silanes of the formula (III) and metal compounds of the formula (V) is 5 to 20 mol%, preferably 10 to 15 mol%, the proportion of the sum of silanes of the formulas (Ia) , (Ib) and (II) 2.5 to 85 mol%, preferably 2.5 to 70 mol%, and the proportion of silanes of the formula (IV) 10 to 80 mol%, preferably 15 to 70 mol% %.

The proportion of the sum of the silanes of the formulas (Ia), (Ib) and (II) should only be in the range of the lower limit of 2.5 mol%, if these are fluorinated compounds. It is advantageous if the proportion of fluorinated silanes is not more than 10 mol% of the sum of the silanes with the formulas (Ia), (Ib) and (II).

As a rule, up to three compounds of the formula (Ia) and (Ib) can be used for a silicic acid (hetero) polycondensate, but in some cases even more.

The inventors have discovered in the course of their work that the production of low polarity by the use of simple Sil (ox) anstrukturen or the incorporation of fluoroalkyl components alone already allows some delamination of PUR materials because surface energies of <20-25 mN / m represent a necessary condition. However, the best results can be achieved with hybrid polymers in which at least 20% of the silicon atoms (or, if appropriate, the sum of silicon and metal atoms) contain two C ₁ -C ₃ -alkyl groups, in particular two methyl groups, if appropriate partly also phenyl groups , It is particularly preferred, as mentioned above, if several silicon atoms with two such groups are linked together directly via oxygen atoms, so that silicone-like structures of the formula -SiR ₂ -O-SiR ₂ -O-SiR ₂ -O with R equal to C ₁ - C ₃ alkyl or phenyl, preferably at least predominantly C ₁ -C ₃ alkyl and especially methyl arise, more preferably at least 10% of the silicon atoms part of such a silicone-like structure of the aforementioned type of at least 3, preferably at least 5 with two C in each case C ₁ -C ₃ alkyl groups are substituted silicon atoms. Among these, more preferably 50-100% are substituted with two methyl groups.

If the silicic acid (hetero) polycondensates according to the invention are used with the use of siloxanes of the structure (Ia), it is advantageous not to add them first to the otherwise already condensed silicic acid polycondensate. Because the resulting sols tend to phase separation, even after application and curing, which u. a. in the formation of thin oil films on the surface can express. Such oil films, because of their high surface tension lowering effect, may cause defects in the production of closed cell flexible foams. On the other hand, if the siloxanes are already mixed with the other compounds (I) to (V) selected as starting materials prior to condensation and subjected to a hydrolytic condensation together with them in the sol-gel process, the surface energy is already reached at about 10% molar fraction lowered to 20 mN / m or below and achieved a good delamination effect.

For coating the mold, known methods are suitable. Spray methods are particularly favorable, because they allow for a clean coating of undercuts.

The controlled covalent incorporation of silicone components and the creation of superficial layers enriched with silicon-like structures represent an innovative approach that combines the outstanding separation-active properties of silicone oils with the favorable mechanical properties of hybrid sol-gel materials in one material. The challenge of incorporating the release ingredients in such a way that the release effect is maintained, but the additives are not washed out or migrate to the surface (oil film formation) could be solved by the present invention. In addition, it has surprisingly been found that a rather low crosslinking density of the material in the industrial process has an advantageous effect, since the process a) becomes so tolerable to variations in layer thickness, and b) low static friction results. Especially the latter plays a major role in the removal of freshly produced moldings from the mold, which may also have undercuts.

• • Es resultieren Trennmittel mit gleichbleibend guter Trennwirkung nach mindestens 200 Formgebungs-/Entformungsprozessen
• • Eine Erneuerung ist nicht oder erst nach sehr vielen Zyklen notwendig (Beschichtung kann bei Bedarf und chemisch abgereinigt werden)
• • Die Trennmittel besitzen eine gleichbleibende niedrige Oberflächenenergie und eine hohe Gleitwirkung
• • Sie zeigen eine geringe thermomechanische Versprödung bei zyklischer Belastung (exemplarisch nachgewiesen mittels Rasterkraftmikroskopie)
• • Sie besitzen eindeutige Vorteile gegenüber kommerziellen und nur semi-permanenten Trennmitteln, da diese nach wenigen Zyklen erneuert werden müssen

The advantages of the invention can be described as follows:

• • This results in release agents with consistently good release effect after at least 200 shaping / demolding processes
• • A renewal is not necessary or only after very many cycles (coating can be cleaned if necessary and chemically)
• • The release agents have a constant low surface energy and a high lubricity
• • They show a low thermo-mechanical embrittlement under cyclic load (exemplified by atomic force microscopy)
• • They have clear advantages over commercial and semi-permanent release agents as they need to be renewed after a few cycles

The invention will be explained in more detail with reference to embodiments.

General exemplary embodiment for the preparation of the silicic acid (hetero) polycondensate according to the invention:
All starting silanes / siloxanes or metal compounds are mixed and submitted. With ice cooling, water or 0.1N HCl is added dropwise. The molar amount of water or aqueous HCl should preferably correspond to the molar amount of all hydrolyzable alkoxide groups. The cooling is then removed and the mixture is allowed to stir for 16 h at 0 ° C until the reaction is complete. The resulting solution is diluted as much with n-propanol (eg in a weight ratio of 1: 1) until a viscosity results which allows the application of the hydrolyzate in a spray process.

• Beispiel 1: 20 Mol-% Tetraethoxysilan, 20 Mol-% Methyltrimethoxysilan, 20 Mol-% Dimethyldimethoxysilan, 10 Mol-% Methoxy-poly(dimethylsiloxan) mit einem Molekulargewicht von etwa 800 bis 1000.
• Beispiel 2: 50 Mol-% Methyltrimethoxysilan, 40 Mol-% Dimethyldimethoxysilan, 10 Mol-% Dimethoxy-poly(dimethylsiloxan) mit einem Molekulargewicht von etwa 800 bis 1000.
• Beispiel 3: 20 Mol-% Tetraethoxysilan, 20 Mol-% Methyltrimethoxysilan, 50 Mol-% Dimethyldimethoxysilan, 10 Mol-% Dihydroxy-poly(dimethyl-diphenylsiloxan) mit einem Molekulargewicht von etwa 800 bis 1000.
• Beispiel 4: 18 Mol-% Aluminium-di-t-butoxi-ethylacetoacetat, 9 Mol-% Trimethoxyphenylsilan, 4,5 Mol-% Triethoxyaminopropylsilan; 10 Mol-% Dimethoxy-poly(dimethylsiloxan) mit einem Molekulargewicht von etwa 800 bis 1000, 58,5 Mol-% Glycidoxypropylpropyl-trimethoxysilan.
• Beispiel 5: 18 Mol-% Aluminium-di-t-butoxi-ethylacetoacetat, 9 Mol-% Trimethoxyphenylsilan, 4,5 Mol-% Triethoxyaminopropylsilan, 10 Mol-% Diethoxy-poly(dimethylsiloxan) mit einem Molekulargewicht von etwa 800 bis 1000, 58,5 Mol-% Glycidoxypropylpropyl-trimethoxysilan.
• Beispiel 6: 80 Mol-% Tetraethoxysilan; 10 Mol-% Methyltrimethoxysilan, 10 Mol-% Diethoxy-poly(dimethylsiloxan) mit einem Molekulargewicht von etwa 800 bis 1000.
• Beispiel 7: 80 Mol-% Tetraethoxysilan; 10 Mol-% Methyltrimethoxysilan, 10 Mol-% Dimethoxy-poly(dimethylsiloxan) mit einem Molekulargewicht von etwa 800 bis 1000.
• Beispiel 8: 80 Mol-% Tetraethoxysilan; 10 Mol-% Methyltrimethoxysilan, 10 Mol-% Dihydroxy-poly(dimethyl-diphenylsiloxan) mit einem Molekulargewicht von etwa 800 bis 1000.
• Beispiel 9: 54 Mol-% Methyltrimethoxysilan, 43 Mol-% Dimethyldimethoxysilan, 3 Mol-% des Triethoxysilyl-polyperfluorisopropyletherpropans, das voranstehend als zweites Beispiel für Silane mit fluorierten Gruppen gezeigt ist.
• Beispiel 10: 80 Mol-% Tetraethoxysilan, 10 Mol-% Methyltrimethoxysilan, 8 Mol-% Dimethoxy-poly(dimethylsiloxan) mit einem Molekulargewicht von etwa 800 bis 1000, 2 Mol.-% des Triethoxysilyl-polyperfluorisopropyletherpropans, das voranstehend als zweites Beispiel für Silane mit fluorierten Gruppen gezeigt ist.
• Beispiel 11: 20 Mol-% Tetraethoxysilan, 20 Mol-% Methyltrimethoxysilan, 50 Mol-% Dimethyldimethoxysilan, 8 Mol-% Dihydroxy-poly(dimethyl-diphenylsiloxan) mit einem Molekulargewicht von etwa 800 bis 1000, 2 Mol-% des Triethoxysilyl-polyperfluorisopropyletherpropans, das voranstehend als zweites Beispiel für Silane mit fluorierten Gruppen gezeigt ist.
• Beispiel 12: 20 Mol-% Tetraethoxysilan, 20 Mol-% Methyltrimethoxysilan, 50 Mol-% Dimethyldimethoxysilan, 8 Mol-% Dimethoxy-poly(dimethylsiloxan) mit einem Molekulargewicht von etwa 800 bis 1000, 2 Mol-% des Triethoxysilyl-polyperfluorisopropyletherpropans, das voranstehend als zweites Beispiel für Silane mit fluorierten Gruppen gezeigt ist.
• Beispiel 13: 80 Mol-% Tetraethoxysilan, 10 Mol-% Methyltrimethoxysilan, 8 Mol-% Dihydroxy-poly(dimethyl-diphenylsiloxan) mit einem Molekulargewicht von etwa 800 bis 1000, 2 Mol-% des Triethoxysilyl-polyperfluorisopropyletherpropans, der voranstehend als zweites Beispiel für Silane mit fluorierten Gruppen gezeigt ist.
• Beispiel 14: 45 Mol-% Methyltrimethoxysilan, 36 Mol-% Dimethyldimethoxysilan, 9 Mol-% Vinyltriethoxysilan, 10 Mol-% Dimethoxy-poly(dimethylsiloxan) mit einem Molekulargewicht von etwa 800 bis 1000.

Exemplary embodiments for the preparation of specific silicic acid (hetero) polycondensates according to the invention:

• Example 1: 20 mol% of tetraethoxysilane, 20 mol% of methyltrimethoxysilane, 20 mol% of dimethyldimethoxysilane, 10 mol% of methoxy-poly (dimethylsiloxane) having a molecular weight of about 800 to 1000.
• Example 2: 50 mol% of methyltrimethoxysilane, 40 mol% of dimethyldimethoxysilane, 10 mol% of dimethoxy-poly (dimethylsiloxane) having a molecular weight of about 800 to 1000.
• Example 3: 20 mol% of tetraethoxysilane, 20 mol% of methyltrimethoxysilane, 50 mol% of dimethyldimethoxysilane, 10 mol% of dihydroxy-poly (dimethyl-diphenylsiloxane) having a molecular weight of about 800 to 1,000.
• Example 4: 18 mol% of aluminum di-t-butoxy-ethylacetoacetate, 9 mol% of trimethoxyphenylsilane, 4.5 mol% of triethoxyaminopropylsilane; 10 mole percent of dimethoxy-poly (dimethylsiloxane) having a molecular weight of about 800 to 1000, 58.5 mole percent of glycidoxypropylpropyltrimethoxysilane.
• Example 5: 18 mol% of aluminum di-t-butoxy-ethylacetoacetate, 9 mol% of trimethoxyphenylsilane, 4.5 mol% of triethoxyaminopropylsilane, 10 mol% of diethoxy-poly (dimethylsiloxane) having a molecular weight of about 800 to 1000, 58.5 mole percent glycidoxypropylpropyltrimethoxysilane.
• Example 6: 80 mole% tetraethoxysilane; 10 mol% of methyltrimethoxysilane, 10 mol% of diethoxypoly (dimethylsiloxane) having a molecular weight of about 800 to 1,000.
• Example 7: 80 mol% tetraethoxysilane; 10 mol% of methyltrimethoxysilane, 10 mol% of dimethoxy-poly (dimethylsiloxane) having a molecular weight of about 800 to 1000.
• Example 8: 80 mole% tetraethoxysilane; 10 mol% of methyltrimethoxysilane, 10 mol% of dihydroxy-poly (dimethyl-diphenylsiloxane) having a molecular weight of about 800 to 1000.
• Example 9: 54 mol% of methyltrimethoxysilane, 43 mol% of dimethyldimethoxysilane, 3 mol% of the triethoxysilyl polyperfluoroisopropyl ether propane shown above as a second example of silanes having fluorinated groups.
• Example 10: 80 mol% of tetraethoxysilane, 10 mol% of methyltrimethoxysilane, 8 mol% of dimethoxy-poly (dimethylsiloxane) having a molecular weight of about 800 to 1000, 2 mol% of triethoxysilyl-polyperfluoroisopropyl ether propane, as described above as a second example of Silane with fluorinated groups is shown.
• Example 11: 20 mol% tetraethoxysilane, 20 mol% methyltrimethoxysilane, 50 mol% dimethyldimethoxysilane, 8 mol% dihydroxypoly (dimethyl-diphenylsiloxane) having a molecular weight of about 800 to 1000, 2 mol% of triethoxysilyl-polyperfluoroisopropyl ether propane , which is shown above as a second example of fluorinated group silanes.
• Example 12: 20 mole% tetraethoxysilane, 20 mole% methyltrimethoxysilane, 50 mole% dimethyldimethoxysilane, 8 mole% dimethoxy-poly (dimethylsiloxane) having a molecular weight of about 800 to 1000, 2 mole% of triethoxysilyl polyperfluoroisopropyl ether propane, is shown above as a second example of fluorinated group silanes.
• Example 13: 80 mole percent tetraethoxysilane, 10 mole percent methyltrimethoxysilane, 8 mole percent dihydroxy-poly (dimethyl-diphenylsiloxane) having a molecular weight of about 800 to 1000, 2 mole percent of the triethoxysilyl-polyperfluoroisopropyl ether propane previously described as a second example is shown for silanes with fluorinated groups.
• Example 14: 45 mol% of methyltrimethoxysilane, 36 mol% of dimethyldimethoxysilane, 9 mol% of vinyltriethoxysilane, 10 mol% of dimethoxypoly (dimethylsiloxane) having a molecular weight of about 800 to 1,000.

Exemplary embodiments for the production of a molding tool:
The silicic acid (hetero) polycondensates obtained in Examples 1 to 8 were each diluted to such an extent that they could be filled into a common spray gun. With this gun metal molds were sprayed, so that in each case a coherent layer was formed. Subsequently, the layer was cured at about 150 ° C to 250 ° C. In the case of Example 5, crosslinking of the groups bonded via carbon to silicon takes place additionally during curing.

For the hardening of PVC and PU nickel molds (nickel galvano) were used, for the hardening of PU foam aluminum molds. In any case, the molds had a trough-shaped form.

When using silanes of the formula (IV) which carry (meth) acrylic groups, hardening with UV light is advantageous for crosslinking the (meth) acrylic-containing radicals as an alternative to heat curing.

Results:

As a starting point and indication of a good separation effect, first the surface energy of the separating layers was determined. The following procedure was used: The wetting angle of water and of methylene iodide was measured. The measurements were put into the following formula: CosQ = (σ _S - σ _LS ) / σ _L with Q = contact angle, σ _S = surface energy solids, σ _LS = interfacial energy between solid and liquid, σ _L = surface tension liquid. The delamination of PU paint was qualitatively determined by means of a simple adhesive film test and the release of PU foam on the force to be applied quantitatively with a spring balance. The qualitative determination is in 1 shown. Specific conditions of the adhesive release test were: Use of a Tesa 4287 adhesive tape with a defined adhesive force of between 6 and 10 N per 25 mm width (analogously to US Pat Standard EN ISO 2409: 2007 for liability assessment. The terms given in the figure mean: PMT 16 = Example 2; PTM 25 = Example 14; CHM 463 = Example 6, 10% in ethanol; PTM 29 = Example 5. The delamination tests with Examples 9 to 13 (fluorinated systems) gave the following results: TABLE 1 De-adhesion tests with fluorinated hybrid systems: example surface energy Demoulding / Pulling force PVC PU / PVC composite 9 16.4 mN / m <50 g approx. 700 g 10 19.3 mN / m <50 g <50 g 11 16.8 mN / m <50 g <50 g 12 16.6 mN / m <50 g approx. 300 g 13 26.7 mN / m <50 g <50 g

The base hybrid layers were compared to semipermanent standard release agents. The silicone release agents are primarily used for Lackenthaftung, the organic wax in PU foam molding. Table 2 Comparison test with commercial semi-permanent systems description composition Surface energy [mN / m] Delamination PU paint Delamination PU foam Frekote R 180 Silicon (aqueous) 19.7 Good nb Frekote D770 Silicone (solvent) 11.8 Good nb Acmosil organic wax 25.5 nb ~ 800 g

Table 3 below shows the results of the non-fluorinated hybrid layer demulsification tests: TABLE 3 example surface energy annotation example 1 19.2 mN / m suitable for IMC Example 2 23.2 mN / m suitable for IMC Example 3 46.9 mN / m suitable for IMC Example 4 15.2 mN / m suitable for IMC Example 5 15.5 mN / m suitable for IMC Example 6 19.2 mN / m suitable for KWS Example 7 23.7 mN / m suitable for KWS Example 8 39.7 mN / m suitable for KWS KWS = Cold PUR soft foam, IMC = Inmoldcoating

• 1) Beispiel PVC-Slush Prozess • Semi-permanentes Serientrennmittel: ca. 10 Entformungszyklen • Trennmittel Beispiel 1: ≥ 200 Entformungszyklen ohne nachlassende Trennwirkung, bei gleichbleibend hoher optischer Qualität (Glanz, Farbort) der entformten Teile. Mit dem für das (IMC)-PVC-Slush-Verfahren favorisierten Schichtkonzept des Beispiels 1, das die Einarbeitung einer vernetzbaren Siliconkomponente in eine mittelhoch vernetzte Polysiloxan-Matrix beinhaltet, ließ sich eine thermisch und mechanisch belastbare Beschichtung mit geringer Oberflächenenergie und Haftreibung realisieren. Sie kann als homogene, defektfreie Beschichtung über industrielle automatisierte Sprühverfahren aufgetragen und bei Bedarf chemisch abgereinigt werden. Sie liegt mit mindestens 200 Zyklen und hervorragender, kaum nachlassender Trennwirkung im PVC-Slush-Prozess weit über den Möglichkeiten der üblicherweise eingesetzten semi-permanenten Trennmittel, und dies bei gleicher optischer Qualität der entformten Teile. Die Beschichtung ist voll kompatibel mit der industriellen Prozesskette zur Herstellung hochwertiger Instrumententafelhäute für die Automobilindustrie.
• 2) Beispiel PUR-Kaltweichschaum Prozess • Serientrennmittel (im Vgl.): 1 Entformungszyklus (nicht-permanentes, externes Trennmittel). • Trennmittel Beispiel 6: 100 Enformungszyklen ohne nachlassende Trennwirkung, bei mittlerer Offenzelligkeit des Schaumes. Auch für die Kaltweichschaumentformung können ein Polysiloxanharze als Matrixmaterial und vernetzbare Siliconadditive eingesetzt werden (siehe PVC-Slush-Verfahren). In diesem Fall sind jedoch höhere Vernetzungsdichten von Vorteil, was die Schichtapplikation anspruchsvoll gestaltet. Bei eher spröden Schichtmaterialien (wie in Beispiel 6 realisiert) muss unbedingt darauf geachtet werden, dass zonal kein zu dicker Auftrag erfolgt, da dies zu Rissbildung und Delamination der Trennschicht führen kann. Dies ist besonders relevant bei komplex geformten, z.B. hinterschnittigen Formoberflächen.

Results under production conditions:

• 1) Example PVC slush process • Semi-permanent serial release agent: approx. 10 demolding cycles • Release agent Example 1: ≥ 200 demolding cycles without decreasing release effect, with consistently high optical quality (gloss, color location) of the demolded parts. With the coating concept of Example 1, which is favored for the (IMC) PVC slush process, which involves the incorporation of a crosslinkable silicone component into a moderately highly crosslinked polysiloxane matrix, it was possible to realize a thermally and mechanically loadable coating with low surface energy and stiction. It can be applied as a homogeneous, defect-free coating via industrial automated spraying processes and chemically cleaned if necessary. With at least 200 cycles and an outstanding, hardly ever-decreasing release effect in the PVC slush process, it is far beyond the capabilities of the semi-permanent release agents commonly used, and this with the same optical quality of the demoulded parts. The coating is fully compatible with the industrial process chain for the production of high quality instrument panel skins for the automotive industry.
• 2) Example of PUR cold soft foam process • Serial release agent (see above): 1 demoulding cycle (non-permanent, external release agent). • Release agent Example 6: 100 molding cycles without decreasing release effect, with medium open cell foam. Also for the cold soft foam forming a polysiloxane resins can be used as matrix material and crosslinkable silicone additives (see PVC slush method). In this case, however, higher crosslink densities are advantageous, which makes the layer application demanding. In the case of rather brittle layer materials (as realized in example 6), it is absolutely necessary to ensure that the application is not too thick on a zonal basis since this can lead to cracking and delamination of the separating layer. This is particularly relevant for complex shaped, eg undercut mold surfaces.

With uniform layer application, the layer with the silicic acid (hetero) polysiloxane according to Example 6 shows consistently high separation efficiency. The topographic analysis ( 2 After 100 demolding cycles shows a microscopically very smooth, homogeneous and completely defect-free surface, which has an extremely low nanorughness and homogeneous distribution in the material contrast. This finding is noteworthy in view of the strong chemical-mechanical stress caused by the foam formation, but also in the light of the spray coating method used. At higher resolution, homogeneously distributed, particulate structures are embedded in a contrast-differentiating matrix. The particle sizes are in the range 5-50 nm.

• A1. Formwerkzeug zum Aushärten von Elastomeren, insbesondere von Polyurethan-Polymeren, gekennzeichnet durch eine auf der Innenseite der Form aufgebrachte Beschichtung aus einem oder umfassend ein Kieselsäure(hetero)polykondensat, in dem über Kohlenstoffatome an Siliciumatome gebundene Kohlenwasserstoffgruppen vorhanden sind, mit den folgenden Maßgaben: (i) Das Kondensat kann neben Silicium 2-, 3- oder vierwertige Metallatome enthalten, die ausschließlich über Sauerstoffatome in das Kondensat-Netzwerk eingebunden sind und ggf. Hydroxy-, Alkoxy- oder sauerstoffgebundene Komplexliganden aufweisen, aber keine Metall-Kohlenstoffbindungen. (ii) Ein Anteil von Siliciumatomen, der mindestens 20 % der Summe aller Silicium- und Metallatome entspricht, weist über Kohlenstoffatome gebundene Gruppen auf. (iii) Höchstens 10 % aller Siliciumatome tragen mehr als 2 über Kohlenstoffatome gebundene Gruppen. (iv) 20–100 Mol-% der über Kohlenstoff gebundenen Gruppen sind ausgewählt unter einer oder mehreren Alkyl-, Aryl-, Arylalkyl- und Alkylarylgruppen (A), deren Kohlenstoffkette, wenn sie mindestens 3 Kohlenstoffatome aufweist, ggf. durch Sauerstoffatome unterbrochen sein kann.
• A2. Formwerkzeug nach Punkt A1, worin die über Kohlenstoffatome gebundenen Gruppen zu 80 bis 100 % ausgewählt sind unter Alkyl- und/oder Phenylgruppen.
• A3. Formwerkzeug nach Punkt A1 oder A2, worin ein Teil der Si-C-gebundenen Gruppen verbrückende Alkylengruppen sind, deren Kohlenstoffkette ggf. durch Heteroatome, insbesondere O oder S, oder Kopplungsgruppen, insbesondere -C(O)-, -C(O)O-, -CO(NH)-, -NHC(O) oder -NHC(O)NH- sowie deren Thioanaloge, unterbrochen sein kann.
• A4. Formwerkzeug nach einem der Punkte A1 bis A3, worin bis zu 30 Mol-% der Alkyl-, Aryl-, Arylalkyl- und/oder Alkylarylgruppen (A) ganz oder teilweise fluoriert sind.
• A5. Formwerkzeugt nach einem der voranstehenden Punkte, worin der gemäß (ii) definierte Anteil an Siliciumatomen 50 bis 100 Mol-%, vorzugsweise annähernd 100% beträgt.
• A6. Formwerkzeug nach einem der voranstehenden Punkte, worin mindestens ein Teil der Gruppen (A) Methyl-, Ethyl- oder Propylgruppen und insbesondere Methylgruppen sind.
• A7. Formwerkzeug nach Punkt A6, worin wenigstens 20 % der Siliciumatome zwei Gruppen (A) aufweisen.
• A8. Formwerkzeug nach Punkt A7, worin mindestens 10 % aller Siliciumatome Bestandteil von Strukturen sind, in denen mindestens 6 Siliciumatome, die jeweils zwei Gruppen (A) aufweisen, direkt über Sauerstoffatome miteinander verknüpft sind.
• A9. Formwerkzeug nach Punkt A8, worin die Gruppen (A) Methylgruppen sind.
• A10. Formwerkzeug nach einem der voranstehenden Punkte, dadurch gekennzeichnet, dass das Kieselsäure(hetero)polykondensat weiterhin über Kohlenstoffatome an Silicium gebundene Gruppen (B), die polare Reste tragen, vorzugsweise ausgewählt unter mit primären Aminogruppen, Ammoniumgruppen, SH-Gruppen, Carbonsäureresten oder aktivierten Carbonsäureresten substituierte Kohlenwasserstoffreste, und/oder über Kohlenstoffatome an Silicium gebundene Gruppen (C), die organisch polymerisierbare C=C-Doppelbindungen oder Epoxygruppen aufweisen, enthält.
• A11. Formwerkzeug nach Punkt A10, worin der Anteil an Gruppen (B) 5–20 % und/oder der Anteil an Gruppen (C) 10 bis 30% beträgt, bezogen auf die Summe aller über Kohlenstoff an Silicium gebundenen Gruppen im Kieselsäure(hetero)polykondensat.
• A12. Formwerkzeug nach einem der voranstehenden Punkte, worin die Innenoberfläche der Form aus Aluminium oder Nickel besteht.
• A13. Verwendung des Formwerkzeugs nach einem der voranstehenden Punkte zum Aushärten und anschließenden Entformen eines Polyurethan-Polymer-Formteils, insbesondere eines PUR-Weichschaum-Formteils.
• B. Kieselsäure(hetero)polykondensat, in welchem über Kohlenstoffatome an Siliciumatome gebundene Kohlenwasserstoffgruppen vorhanden sind, mit den folgenden Maßgaben: (i) das Kondensat kann neben Silicium 2-, 3- oder vierwertige Metallatome enthalten, die ausschließlich über Sauerstoffatome in das Kondensat-Netzwerk eingebunden sind und ggf. Hydroxy-, Alkoxy- oder sauerstoffgebundene Komplexliganden aufweisen, aber keine Metall-Kohlenstoffbindungen, (ii) ein Anteil von Siliciumatomen, der mindestens 20 % der Summe aller Silicium- und Metallatome entspricht, weist über Kohlenstoffatome gebundene Gruppen auf, (iii) höchstens 10 % aller Siliciumatome tragen mehr als 2 über Kohlenstoffatome gebundene Gruppen, (iv) 20–100 Mol-% der über Kohlenstoff gebundenen Gruppen sind ausgewählt unter einer oder mehreren C₁-C₃-Alkyl- oder Phenylgruppen (A), dadurch gekennzeichnet, dass mindestens 20 % der Siliciumatome zwei Gruppen (A) aufweisen und mindestens 10 % aller Siliciumatome Bestandteil von Strukturen sind, in denen mindestens 6 Siliciumatome, die jeweils zwei Gruppen (A) aufweisen, direkt über Sauerstoffatome miteinander verknüpft sind.
• C. Verfahren zum Herstellen von Formteilen aus einem organischen oder teilorganischen Polymermaterial, worin das flüssige oder pastöse Polymermaterial in ein Formwerkzeug nach einem der Punkte 1 bis 12 eingebracht, insbesondere unter Druck eingespritzt, sodann unter erhöhten Temperaturen und/oder erhöhtem Druck einer Vernetzung unterworfen wird, worauf das Formteil aus der Form genommen wird.

In summary, the invention relates, inter alia, to the following embodiments:

• A1. Mold for curing elastomers, in particular polyurethane polymers, characterized by a coating applied on the inside of the mold of or comprising a silicic acid (hetero) polycondensate in which hydrocarbon groups bonded via carbon atoms to silicon atoms are present, with the following provisos: i) In addition to silicon, the condensate may contain 2-, 3- or tetravalent metal atoms which are exclusively bound to the condensate network via oxygen atoms and may have hydroxy-, alkoxy- or oxygen-bonded complex ligands, but no metal-carbon bonds. (ii) A proportion of silicon atoms corresponding to at least 20% of the sum of all silicon and metal atoms has groups bonded via carbon atoms. (iii) Not more than 10% of all silicon atoms carry more than 2 carbon-bonded groups. (iv) 20-100 mol% of the carbon-bonded groups are selected from one or more alkyl, aryl, arylalkyl and alkylaryl groups (A) whose carbon chain, if it has at least 3 carbon atoms, may be interrupted by oxygen atoms can.
• A2. A mold according to item A1, wherein the groups bonded via carbon atoms are selected from 80 to 100% among alkyl and / or phenyl groups.
• A3. Forming tool according to item A1 or A2, wherein part of the Si-C-bonded groups are bridging alkylene groups whose carbon chain is optionally substituted by heteroatoms, in particular O or S, or coupling groups, in particular -C (O) -, -C (O) O -, -CO (NH) -, -NHC (O) or -NHC (O) NH- and their thio analogues, may be interrupted.
• A4. Mold according to one of the points A1 to A3, wherein up to 30 mol% of the alkyl, aryl, arylalkyl and / or alkylaryl groups (A) are completely or partially fluorinated.
• A5. Mold according to one of the preceding points, wherein the proportion of silicon atoms defined in (ii) is 50 to 100 mol%, preferably approximately 100%.
• A6. Mold according to one of the preceding points, wherein at least a part of the groups (A) are methyl, ethyl or propyl groups and in particular methyl groups.
• A7. A mold according to item A6, wherein at least 20% of the silicon atoms have two groups (A).
• A8. A mold according to item A7, wherein at least 10% of all silicon atoms are part of structures in which at least 6 silicon atoms, each having two groups (A), are linked together directly via oxygen atoms.
• A9. A mold according to item A8, wherein the groups (A) are methyl groups.
• A10. Molding tool according to one of the preceding points, characterized in that the silicic acid (hetero) polycondensate furthermore carries carbon-bonded groups (B) which carry polar radicals, preferably selected from among primary amino groups, ammonium groups, SH groups, carboxylic acid radicals or activated carboxylic acid radicals Substituted hydrocarbon radicals, and / or carbon atoms bonded to silicon groups (C) having organically polymerizable C = C double bonds or epoxy groups.
• A11. Forming tool according to item A10, wherein the proportion of groups (B) is 5-20% and / or the proportion of groups (C) 10 to 30%, based on the sum of all bonded via silicon to silicon groups in the silica (hetero) polycondensate ,
• A12. A molding tool according to any one of the preceding claims, wherein the inner surface of the mold is made of aluminum or nickel.
• A13. Use of the mold according to one of the preceding points for curing and subsequent demolding of a polyurethane-polymer molding, in particular a PUR flexible foam molding.
• Example, silicic acid (hetero) polycondensate in which carbon atoms bonded to silicon atoms hydrocarbon groups are present, with the following provisos: (i) the condensate may contain in addition to silicon 2-, 3- or tetravalent metal atoms, which exclusively via oxygen atoms in the condensate Network and may have hydroxy, alkoxy or oxygenated complex ligands, but no metal-carbon bonds, (ii) a proportion of silicon atoms corresponding to at least 20% of the sum of all silicon and metal atoms has groups bonded via carbon atoms, (iii) at most 10% of all silicon atoms carry more than 2 groups bonded via carbon atoms, (iv) 100 mol% of the carbon-bonded groups are selected from one or more C ₁ -C ₃ alkyl or phenyl groups (A), characterized in that at least 20% of the silicon atoms have two groups (A) and at least 10% of all silicon atoms Are part of structures in which at least 6 silicon atoms, each having two groups (A), are linked together directly via oxygen atoms.
• C. A method for producing moldings from an organic or partially organic polymer material, wherein the liquid or pasty polymer material is introduced into a mold according to one of the items 1 to 12, in particular injected under pressure, then subjected to crosslinking under elevated temperatures and / or pressure , whereupon the molding is removed from the mold.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited non-patent literature

• http://www.atzonline.de/Aktuell/Nachrichten/1/6531/New-TPU-Werkstoff-fuer-Dekorhaeutekaelteflexibelkomma-weichmacher--and-halogenfrei.html [0004]
• Standard EN ISO 2409: 2007 [0051]

Claims (15)

A mold for curing elastomers, in particular polyurethane polymers, characterized by a coating applied on the inside of the mold comprising or comprising a silicic acid (hetero) polycondensate in which hydrocarbon groups bonded via carbon atoms to silicon atoms are present, with the following provisos: (i) the condensate may contain, in addition to silicon, 2-, 3- or tetravalent metal atoms which are exclusively bound to the condensate network via oxygen atoms and may have hydroxy-, alkoxy- or oxygen-bonded complexing ligands, but no metal-carbon bonds, (ii) a proportion of silicon atoms corresponding to at least 20% of the sum of all silicon and metal atoms has groups bonded via carbon atoms. (iii) at most 10% of all silicon atoms carry more than 2 groups bonded via carbon atoms, (iv) 20-100 mol% of the carbon-bonded groups are selected from one or more alkyl, aryl, arylalkyl and alkylaryl groups (A) whose carbon chain, if it has at least 3 carbon atoms, may be interrupted by oxygen atoms can. A mold according to claim 1, wherein the groups bonded via carbon atoms are selected from 80 to 100% among alkyl and / or phenyl groups. A molding tool according to claim 1 or 2, wherein part of the Si-C-bonded groups are bridging alkylene groups whose carbon chain is optionally substituted by heteroatoms, in particular O or S, or coupling groups, in particular -C (O) -, -C (O) O -, -CO (NH) -, -NHC (O) or -NHC (O) NH- and their thio analogues, may be interrupted. Mold according to one of claims 1 to 3, wherein up to 30 mol% of the alkyl, aryl, arylalkyl and / or alkylaryl groups (A) of the condensate are completely or partially fluorinated. Mold according to one of the preceding claims, in which the proportion of silicon atoms defined in (ii) is 50 to 100 mol%, preferably approximately 100%. Mold according to one of the preceding claims, in which at least a part of the groups (A) are methyl, ethyl or propyl groups and in particular methyl groups. A mold according to claim 6, wherein at least 20% of the silicon atoms have two groups (A). A mold according to claim 7, wherein at least 10% of all silicon atoms are part of structures in which at least 6 silicon atoms, each having two groups (A), are linked together directly via oxygen atoms. A mold according to claim 8, wherein the groups (A) are methyl groups. Mold according to one of the preceding claims, characterized in that the silicic acid (hetero) polycondensate further bonded via carbon atoms to silicon groups (B) bearing polar radicals, preferably selected from among primary amino groups, ammonium groups, SH groups, carboxylic acid residues or activated carboxylic acid residues Substituted hydrocarbon radicals, and / or carbon atoms bonded to silicon groups (C) having organically polymerizable or polymerized C = C double bonds or epoxy groups. A molding tool according to claim 10, wherein the proportion of groups (B) is 5-20% and / or the proportion of groups (C) 10 to 30%, based on the sum of all groups bonded via silicon to silicon in the silicic acid (hetero) polycondensate , A mold according to any one of the preceding claims, wherein the inner surface of the mold is made of aluminum or nickel. Use of the mold according to one of the preceding claims for curing and subsequent demolding of a polyurethane polymer molding, in particular a PUR flexible foam molding. Silica (hetero) polycondensate in which hydrocarbon groups bonded via carbon atoms to silicon atoms are present, with the following provisos: (i) the condensate can contain, in addition to silicon, 2-, 3- or tetravalent metal atoms which are bound exclusively via oxygen atoms in the condensate network and optionally having hydroxy-, alkoxy- or oxygen-bonded complexing ligands, but no metal-carbon bonds, (ii) a proportion of silicon atoms corresponding to at least 20% of the sum of all silicon and metal atoms has groups bonded via carbon atoms, (iii ) At most 10% of all silicon atoms carry more than 2 carbon-bonded groups. (iv) 20-100 mole% of the carbon-bonded groups are selected from one or more C ₁ -C ₃ alkyl or phenyl groups (A) characterized in that at least 20% of the silicon atoms have two groups (A) and at least 10% of all silicon atoms Bestan These are part of structures in which at least 6 silicon atoms, each having two groups (A), are linked together directly via oxygen atoms. A process for producing moldings from an organic or partially organic polymer material, wherein the liquid or pasty polymer material is introduced into a mold according to one of claims 1 to 12, in particular injected under pressure, then subjected to crosslinking at elevated temperatures and / or elevated pressure, whereupon the molding is removed from the mold.

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