DE102019220101A1 - Moisture-crosslinkable, dimensionally stable polymer mass - Google Patents

Abstract

The aim is to provide a mass which can be hardened with atmospheric moisture, which can be applied in a simple manner and with very precise positioning and, after hardening, produces high adhesive strengths. This is achieved with a chemically pre-crosslinked and further crosslinkable with moisture, autohesive polymer composition for use as a layered body that can be applied to a substrate, the polymer composition having at least one polymer with at least two terminal silyl groups according to the formula (1) Si (R1) a (R2) b (1 ), where the radicals R1 stand independently of one another for an alkyl, alkenyl or aryl group or for a hydrogen atom, the radicals R2 stand for a group which can be split off with water and b = 1, 2 or 3 and a = 3 - b; and at least one condensation catalyst. The invention also relates to the use of such a polymer composition for producing permanent bonds.

Description

The invention lies generally in the technical field of polymer compositions as used in household and technology for a wide variety of applications. More specifically, the invention relates to a pre-crosslinked auto-adhesive polymer mass which can be further crosslinked with moisture. In particular, it is dimensionally stable enough to be applied as a laminate to a substrate and used, for example, in construction applications.

Polymer systems that have reactive silyl groups are known, e.g. as a basis for sealant and adhesive formulations. They are characterized by their good adhesion to many surfaces. In particular, they are able to form a very stable and permanent connection to substrate surfaces.

The polymers are able to enter into condensation reactions with one another at room temperature either under the influence of moisture from the environment or mediated by added crosslinkers. Depending on the content of reactive silyl groups and their structure, mainly long-chain polymers with thermoplastic properties, rather wide-meshed, three-dimensional networks with mainly elastomeric properties or highly cross-linked systems with thermoset properties are formed.

The polymers have an organic basic structure, e.g. a polyurethane, polyester or polyether basic structure, or are based on a silicone basic structure. All the systems of interest here have in common that the polymers have terminal silyl groups, which in turn carry either OH groups or groups that can be split off with water, e.g. alkoxy or acyloxy groups.

Polymers with silyl groups at the termini or in a side chain are for example in EP 1 396 513 A1 described. According to the document, the silyl groups with their removable substituents are obtained by adding a hydrosilane to terminal double bonds of the framework polymer, by reacting isocyanatosilanes with hydroxyl groups of the polymer, by reacting silanes containing active hydrogen atoms with isocyanate-functionalized polymers or by reacting mercaptosilanes with terminal double bonds of the Polymers introduced. The polymers functionalized in this way are the basis of compositions that are used as adhesives or sealants.

1. a) mindestens einen Polyether und/oder mindestens einen Polyacrylsäureester mit mindestens einer Endgruppe -A_n-R-SiXYZ, worin A eine zweibindige Bindegruppe, R ein zweibindiger, gegebenenfalls ein Heteroatom enthaltender Kohlenwasserstoffrest mit 1-12 C-Atomen, und X, Y, Z unabhängig voneinander C₁-C₈-Alkyl, C₁-C₈-Alkoxy oder C₁-C₈-Acyloxyreste sind, wobei m8indestens einer der Reste eine C₁-C₈-Alkoxy- oder C₁-C₈-Acyloxygruppe ist, und n 0 oder 1 ist; sowie
2. b) mindestens eine zinnorganische Verbindung,
3. c) mindestens eine Verbindung, die frei von Zinn- und Siliziumatomen ist und die mindestens zwei Funktionen aufweist, die jeweils ausgewählt sind aus Carboxy-, Carbonyl-, Hydroxygruppen sowie Stickstoffatomen, die Bestandteil eines Ringsystems mit aromatischem Charakter sind.

WO 2011/051385 A2 relates to a curable composition which comprises the following components:

1. a) at least one polyether and / or at least one polyacrylic acid ester with at least one end group -A _n -R-SiXYZ, where A is a divalent bonding group, R is a divalent, optionally heteroatom-containing hydrocarbon radical with 1-12 C atoms, and X, Y , Z are independently C ₁ -C ₈ -alkyl, C ₁ -C ₈ -alkoxy or C ₁ -C ₈ -acyloxy radicals, at least one of the radicals being a C ₁ -C ₈ -alkoxy or C ₁ -C ₈ - Is acyloxy group and n is 0 or 1; such as
2. b) at least one organotin compound,
3. c) at least one compound which is free of tin and silicon atoms and which has at least two functions, each selected from carboxy, carbonyl, hydroxyl groups and nitrogen atoms which are part of a ring system with aromatic character.

The composition should enable a longer processing phase with a subsequent short curing time.

1. (A) das Umsetzen
   1. a. mindestens einer Polyolverbindung mit einem Molekulargewicht von 4000 - 20000 Dalton mit
   2. b. einem Diisocyanat bei einem stöchiometrischen Überschuss der Diisocyanatverbindung gegenüber den OH-Gruppen der Polyolverbindungen, wodurch ein Polyurethan-Prepolymer gebildet wird, das Isocyanat-terminiert ist; und
2. (B) das Umsetzen des Polyurethan-Prepolymers mit einem oder mehreren OHterminierten Silanen der Formel HO-R³-C(O)-N(R⁴)-R-Si(R¹)_m(OR²)_3-m, worin m 0, 1 oder 2 ist, R¹ und R² Alkylreste mit 1 bis 4 Kohlenstoffatomen, R³ ein divalenter organischer Rest mit 1 bis 10 Atomen ausgewählt aus C, N, S und/oder O in der Kette ist, R⁴ ein Wasserstoffatom oder ein Alkylrest mit 1 bis 12 Kohlenstoffatomen ist und R eine difunktionelle organische Gruppe ist, um die Isocyanatgruppen des Prepolymers mit dem vorstehenden Silan zu verkappen.

Subject of WO 2009/130298 A1 is a process for making a silylated polyurethane comprising:

1. (A) the repositioning
   1. a. at least one polyol compound with a molecular weight of 4,000-20,000 Daltons
   2. b. a diisocyanate in the case of a stoichiometric excess of the diisocyanate compound over the OH groups of the polyol compounds, whereby a polyurethane prepolymer is formed which is isocyanate-terminated; and
2. (B) the reaction of the polyurethane prepolymer with one or more OH-terminated silanes of the formula HO-R ³ -C (O) -N (R ⁴ ) -R-Si (R ¹ ) _m (OR ² ) _3-m , where m is 0, 1 or 2, R ¹ and R ^{2 are} alkyl radicals with 1 to 4 carbon atoms, R ^{3 is} a divalent organic radical with 1 to 10 atoms selected from C, N, S and / or O in the chain, R ⁴ is hydrogen or an alkyl group having 1 to 12 carbon atoms; and R is a difunctional organic group to cap the isocyanate groups of the prepolymer with the above silane.

In the case of polymer systems that crosslink via reactive silyl groups, a distinction can be made between one-component and two-component compositions.

One-component systems usually have several hydrolyzable silyl groups. The polymers functionalized in this way generally result from the reaction of an OH-terminated polymer with a silane crosslinker which has several groups that can be split off with water. This reaction takes place with the exclusion of moisture, i.e. even during simple mixing or after filling the mixture into airtight cartridges, but it requires the presence of a condensation catalyst.

If the now “end-capped” polymer is applied, water diffuses in from the ambient air and initiates the actual crosslinking reaction, which proceeds with hydrolysis of the hydrolyzable silyl groups and subsequent condensation of the Si-OH groups formed in this way to form a network.

In the case of two-component systems, the Si-OH-terminated polymer is present as a first component, while the silane crosslinker is kept available separately, together with a condensation catalyst, as the second component. As soon as the two components are brought together, crosslinking of the polymers takes place through condensation reactions mediated by the crosslinker. This crosslinking reaction does not require any additional moisture.

In the environment described here, special attention is often paid to silicone-based polymers, which are particularly characterized by their resistance to external influences such as temperature and precipitation. That is why they are often used in construction for assembly applications. Very thick adhesive layers or adhesive tapes are often required here, not least in order to achieve the required high adhesive strengths.

Among the silicone-based systems, a distinction is made between cold-curing and warm-curing silicone compounds. The former are known as RTV silicone compounds, where “RTV” stands for “room temperature vulcanization” or “room temperature crosslinking”. The second-mentioned compounds are referred to as HTV silicone compounds, with “HTV” standing for “high temperature vulcanization” or “high temperature crosslinking”. RTV systems are often preferred because their use does not involve the use of elevated temperatures and thus the substrates to be glued or sealed are not exposed to such influences. A distinction is made between RTV1 systems and RTV2 systems, where RTV1 compounds network in accordance with the mechanism described above for one-component systems and RTV2 compounds in accordance with the mechanism for two-component systems.

1. a) ein Organopolysiloxan mit einer Viskosität von mindestens 1000 mPas bei 25 °C und mindestens zwei Si-gebundenen Hydroxygruppen und/oder Si-gebundenen hydrolysierbaren Gruppen;
2. b) gefälltes Calciumcarbonat als Füllstoff;
3. c) einen geeigneten Katalysator;
4. d) einen Vernetzer, der geeignet ist, unter Katalyse durch c) mit Komponente a) zu reagieren; und optional
5. e) einen oder mehrere Rheologiemodifizierer;
6. f) bis zu 10 Gew.-% einen oder mehrere Verlängerer oder Weichmacher;

wobei Komponente b) in einem Anteil von 50 bis 70 Gew.-% der Gesamtzusammensetzung vorhanden ist. WO 2012/119940 A1 has as its subject a room temperature crosslinking organopolysiloxane composition which already has strength in the uncrosslinked state and comprises the following components:

1. a) an organopolysiloxane with a viscosity of at least 1000 mPas at 25 ° C. and at least two Si-bonded hydroxyl groups and / or Si-bonded hydrolyzable groups;
2. b) precipitated calcium carbonate as filler;
3. c) a suitable catalyst;
4. d) a crosslinker which is suitable for reacting with component a) under catalysis by c); and optional
5. e) one or more rheology modifiers;
6. f) up to 10% by weight of one or more extenders or plasticizers;

component b) being present in a proportion of 50 to 70% by weight of the total composition.

1. a) mindestens ein vernetzbares Diorganopolysiloxan;
2. b) mindestens ein oligomeres Siloxan als Vernetzer für das Diorganopolysiloxan, wobei das oligomere Siloxan ein Kondensationsprodukt von monomeren Silanvernetzern ist; und
3. c) mindestens ein funktionalisiertes Oligodimethylsiloxan.

WO 2014/086638 A1 describes a one- or two-component silicone formulation that

1. a) at least one crosslinkable diorganopolysiloxane;
2. b) at least one oligomeric siloxane as a crosslinker for the diorganopolysiloxane, the oligomeric siloxane being a condensation product of monomeric silane crosslinkers; and
3. c) at least one functionalized oligodimethylsiloxane.

The composition should be particularly suitable as an elastic adhesive or sealant, especially in the automotive, solar, facade construction, insulating glass, window glass or general construction sectors.

• A eine Siloxanpolymerzusammensetzung umfassend
  1. a) ein Organopolysiloxan, welches mindestens zwei Gruppen ausgewählt aus
     1. i. Si-gebundenen Alkenylgruppen oder
     2. ii. Si-gebundenen Hydroxygruppen und/oder hydrolysierbaren Gruppen
     umfassen kann;
  2. b) einen oder mehrere Füllstoffe;
  und ein Vernetzungssystem umfassend
  • c) einen geeigneten Katalysator und gegebenenfalls
  • d) zur Reaktion mit a) unter Katalyse durch c) geeignete Vernetzer; sowie
  eine oder beide der Komponenten B und C, worin
• B ein oder mehrere Heißschmelzharze darstellt und
• C ein oder mehrere Wachse mit einer Schmelztemperatur zwischen 40 und 200 °C und/oder ein organisches Harz mit einem viskositätsmittleren Molekulargewicht von 200 bis 6000 und einem Erweichungspunkt von 0 bis 150 °C darstellt;

wobei der Gesamtanteil der Komponenten B und/oder C an der Zusammensetzung von 2 bis 60 Gew.-% beträgt. WO 2007/009871 A2 discloses a hot melt coating / adhesive containing:

• A comprising a siloxane polymer composition
  1. a) an organopolysiloxane which is selected from at least two groups
     1. i. Si-bonded alkenyl groups or
     2. ii. Si-bonded hydroxyl groups and / or hydrolyzable groups
     may include;
  2. b) one or more fillers;
  and comprising a networking system
  • c) a suitable catalyst and optionally
  • d) for reaction with a) with catalysis by c) suitable crosslinkers; such as
  one or both of components B and C, wherein
• B represents one or more hot melt resins and
• C represents one or more waxes with a melting temperature between 40 and 200 ° C and / or an organic resin with a viscosity average molecular weight of 200 to 6000 and a softening point of 0 to 150 ° C;

the total proportion of components B and / or C in the composition being from 2 to 60% by weight.

Common polymer-based compositions that cure via reactive silyl groups and have a property profile such that they are suitable for producing adhesive connections between two substrates are pasty mixtures and have little or no dimensional stability. They are therefore not suitable for use as or in a layered body, in particular not as an adhesive for an adhesive tape. A mass without sufficient cohesion or dimensional stability would flow or be squeezed out. In addition, the residue-free removal of a release liner and, in general, residue-free unwinding, e.g. from a roll, would not be possible.

On the other hand, there is great interest in adhesives which cure with atmospheric moisture, are easy to apply and, after crosslinking, have high bond strengths.

The object of the invention is therefore to provide a mass which can be hardened with atmospheric moisture, which can be applied in a simple manner and with very precise positioning, and which can transmit high forces after hardening.

The solution to the problem is based on the idea of providing a compound which cross-links via reactive silyl groups and which can be cross-linked in stages.

worin die Reste R¹ voneinander unabhängig für eine Alkyl-, Alkenyl- oder Arylgruppe oder für ein Wasserstoffatom stehen,
die Reste R² für eine mit Wasser abspaltbare Gruppe stehen und
b = 1, 2 oder 3 und a = 3 — b ist;
umfasst.A first and general object of the invention is a chemically pre-crosslinked and further crosslinkable with moisture, autohesive polymer composition for use as a laminate which can be applied to a substrate and which contains at least one polymer with at least two terminal silyl groups according to the formula (1) $$\text{Si}{\left({\text{R.}}^1\right)}_{\text{a}}{\left({\text{R.}}^2\right)}_{\text{b}}$$

in which the radicals R ¹ independently of one another represent an alkyl, alkenyl or aryl group or a hydrogen atom,
the radicals R ² stand for a group which can be split off with water and
b = 1, 2 or 3 and a = 3 - b;
includes.

A “layer body that can be applied to a substrate” is understood to mean a material which is shaped into a layer and which essentially retains its shape and dimensions when applied to a substrate without major external influences. In addition, the laminate can preferably be wound onto itself, if necessary using a release liner. The suitability of a polymer composition according to the invention for use in such a layered body therefore requires that the composition is sufficiently dimensionally stable to be applied, but also to be wound, stacked or otherwise packed or processed without flowing out or being squeezed out. In addition, although already pre-crosslinked, the mass can be further crosslinked by moisture, for example atmospheric humidity, in that the silyl groups are hydrolyzed and the resulting Si-OH groups condense with other Si-OH or hydrolyzable groups of two or more macromolecules.

A “polymer mass” is understood to mean a composition which contains one or more polymers in a significant proportion that is relevant with regard to its properties. The proportion of the total of all polymers with at least two terminal silyl groups according to the formula (1) (these polymers also being referred to below as “Pol _sil ”) in the polymer composition according to the invention is preferably at least 15% by weight, more preferably at least 20% by weight %, particularly preferably at least 25% by weight, in particular at least 30% by weight, for example at least 35% by weight.

“Chemically pre-crosslinked” is understood to mean that between at least some of the macromolecules originally used to produce the polymer mass, a link has already taken place with the formation of chemical bonds, which is more cohesive than the completely uncrosslinked macromolecules intended for the production of the polymer mass expresses. However, this crosslinking is not yet complete, which is why the polymer mass can still be crosslinked. The chemical pre-crosslinking can take place via an auxiliary material provided for this purpose and / or an initial reaction of individual macromolecules with one another. Instead of “chemically pre-crosslinked”, the expression “chemically partially crosslinked” can also be used.

The extent of the crosslinking of the polymer mass determines, among other things, the quotient of loss modulus (G ") and storage modulus (G '), which is referred to as tan δ. The more strongly a polymer mass is crosslinked, the smaller this quotient becomes; it reaches the point of maximum crosslinking for the mass in question its minimum and the mass thus its closest approximation to the properties of an elastic solid.

The quotient of loss modulus (G ") and storage modulus (G ') (tan δ) of a polymer mass according to the invention is preferably at least twice as great, more preferably at least 2.5 times as great and in particular at least 3 times as great as that for this mass, all other things being equal Conditions achievable minimum of the tan δ In other words, the mass is only networked to a certain extent and can network on its own, ie in particular without further addition of crosslinkers, up to the tan δ minimum achievable for it. This implies advantageously a relevant flowability of the mass, ie a significant proportion of viscous flowability, which in turn means that the mass can flow onto a substrate to a certain extent and thus wet it. The mass therefore has a tack, a so-called “tack”. , which ensures that the mass in the only pre- or partially crosslinked state in the expression of its properties of an H adhesive is similar and can accordingly be used advantageously.

“Further crosslinkable with moisture” is understood to mean that the chemically pre-crosslinked polymer mass can (further) crosslink under the action of water, in particular only under the action of atmospheric moisture, with the formation of chemical bonds, which leads to a further build-up of cohesion within compared to the pre-crosslinked state the crowd comes.

“Auto-adhesive” is understood to mean that the polymer mass has a perceptible inherent tack and thus builds up an immediate adhesion to technically common material surfaces with a certain pressure, i.e. has a technically relevant tack or tack. The term “auto-adhesive” is understood in the present case to distinguish it from a “pressure-sensitive adhesive” which has its pressure-sensitive tackiness permanently, while the polymer material according to the invention has its (only) pre-crosslinked state Self-tack is largely lost as a result of the further crosslinking, without, however, losing the adhesion to the substrates that was established before the further crosslinking.

The polymer mass according to the invention can also be referred to as a self-supporting polymer mass. As described, it can be used as a layer body which is inherently dimensionally stable. In this sense, the mass as such can form the layer body, but it can also function as a layer in a multilayer structure. The polymer composition according to the invention is preferably an auto-adhesive polymer composition which is chemically pre-crosslinked and can be further crosslinked with moisture for use in an adhesive tape. The mass is therefore particularly dimensionally stable so that it does not flow out or be squeezed out during normal uses or storage processes of an adhesive tape, e.g. when applying the adhesive tape to a substrate to be bonded and when rolling or winding the adhesive tape into a roll or spool. The adhesive tape is particularly preferably a structural adhesive tape or an adhesive tape for producing structural bonds.

According to the invention, the polymer composition comprises at least one polymer with at least two terminal silyl groups according to the formula (1).

The radicals R ² according to formula (1) which can be split off with water are preferably selected from the group consisting of alkoxy, acyloxy, amino, enoxy and ketoxime groups; they are particularly preferably selected from the group consisting of methoxy, ethoxy, methyl ethyl ketoxime and methyl isobutyl ketoxime groups.

The variable b according to formula (1) is preferably 2 or 3, in particular 3.

The radicals R ¹ according to the formula (1) are preferably selected from the group consisting of methyl, ethyl, phenyl and vinyl groups.

The terminal silyl groups according to the formula (1) are preferably selected independently of one another from the group consisting of vinyldimethoxysilyl, vinyldiethoxysilyl, methyldimethoxysilyl, methyldiethoxysilyl, trimethoxysilyl, triethoxysilyl, methylbis (methylethylketoxime) silyl, tris (methylethylketoxime) silyl, tris (methylethylketoxime) silyl , Vinyl bis (methyl ethyl ketoxime) silyl, vinyl bis (methyl isobutyl ketoxime) silyl, methyl bis (methyl isobutyl ketoxime) silyl and tris (methyl isobutyl ketoxime) silyl groups.

The basic structure of the polymer with at least two terminal silyl groups according to the formula (1) (Pol _sil ) is preferably selected from the group consisting of polyethers, polyurethanes, polysiloxanes, polyureas, polyacrylates, polyolefins and polyesters, and copolymers of these.

• - die Reste R" unabhängig voneinander für eine Alkyl-, Alkenyl-, Aryl-, Alkoxy- oder Ketoximgruppe oder für ein Wasserstoffatom stehen;
• - die Reste R' unabhängig voneinander für Alkyl-, Aryl- oder Alkenylreste stehen;
• - n ≥ 2, m > 0 sowie o, p ≥ 0 gilt; und
• - mindestens zwei der Siloxan-Einheiten (R"₃SiO_1/2) den vorstehend beschriebenen terminalen Silylgruppen gemäß der Formel (1) entsprechen.

The polymer Pol _sil is particularly preferably an organopolysiloxane, in particular an organopolysiloxane based on siloxane units according to the formula (2) (R " ₃ SiO _1/2 ) _n (R ' ₂ SiO) _m (R'SiO _3/2 ) _o (SiO ₂ ) _p (2), wherein

• the radicals R ″ independently of one another represent an alkyl, alkenyl, aryl, alkoxy or ketoxime group or a hydrogen atom;
• - the radicals R 'independently of one another represent alkyl, aryl or alkenyl radicals;
• - n ≥ 2, m> 0 and o, p ≥ 0 applies; and
• - At least two of the siloxane units (R " ₃ SiO _1/2 ) correspond to the terminal silyl groups described above according to the formula (1).

The formula (2) is not a structural formula and in this respect only reflects the composition of the organopolysiloxane from the siloxane units, but not their interlinking.

• - mindestens ein Polymer Poll,
  • dessen Termini voneinander unabhängig jeweils von einer Silylgruppe gemäß der Formel (1) gebildet werden,
• - mindestens ein Polymer Pol2,
  • das mindestens zwei terminale, Si-gebundene OH-Gruppen aufweist;
• - mindestens ein Organosilan und/oder mindestens ein Organooligosiloxan,
  • jeweils enthaltend mindestens drei Si-gebundene, mit Wasser abspaltbare Gruppen; und
• - mindestens einen Kondensationskatalysator.

In one embodiment, the polymer composition according to the invention can be obtained by mixing a composition comprising:

• - at least one polymer poll,
  • whose terms are each formed independently of one another by a silyl group according to the formula (1),
• - at least one polymer Pol2,
  • which has at least two terminal, Si-bonded OH groups;
• - at least one organosilane and / or at least one organooligosiloxane,
  • each containing at least three Si-bonded groups which can be split off with water; and
• - At least one condensation catalyst.

The polymer Poll is preferably a diorganopolysiloxane according to the formula (3) (R ² ) _b (R ¹ ) _a Si-O- (SiR ' ₂ -O) _m -Si (R ¹ ) _a (R ² ) _b (3), in which the radicals R 'have the meaning given for formula (2), m> 0 and R ¹ , R ² , a and b have the meaning according to formula (1). In principle, the radicals R 'can be distributed over the diorganopolysiloxane in all conceivable and chemically possible constellations. Polydimethylsiloxanes, poly (methylphenyl) siloxanes and poly (dimethylsiloxane / diphenylsiloxane) copolymers are known, for example.

The radicals R 'in the formula (3) preferably represent, independently of one another, methyl, ethyl or phenyl radicals. The diorganopolysiloxane of the formula (3) is particularly preferably a polydimethylsiloxane, a poly (methylphenyl) siloxane or a dimethylsiloxane-diphenylsiloxane copolymer, very particularly preferably a polydimethylsiloxane. The formula (3) is a structural formula, so it also shows the linkage between the siloxane units.

The polymer Poll preferably has a number-average molecular weight M _n (according to the measurement method described herein) of 40,000 to 150,000 g / mol, more preferably of 60,000 to 90,000 g / mol.

The polymer Poll likewise preferably has a viscosity of 60 to 90 Pa · s, particularly preferably 70 to 90 Pa · s (according to DIN 53019 , Plate-plate).

The polymer Pol2 is preferably a diorganopolysiloxane according to the formula (4) (OH) (R ¹ ) ₂ Si-O ^- (SiR ' ₂ -O) _m -Si (R ¹ ) ₂ (OH) (4), in which the radicals R 'have the meaning given for formula (2), m> 0 applies and the radicals R ^{1 have} the meaning according to formula (1). In principle, the radicals R 'can be distributed over the diorganopolysiloxane in all conceivable and chemically possible constellations. Polydimethylsiloxanes, poly (methylphenyl) siloxanes and poly (dimethylsiloxane / diphenylsiloxane) copolymers are known, for example.

The radicals R 'in the formula (4) preferably represent, independently of one another, methyl, ethyl or phenyl radicals. The diorganopolysiloxane according to formula (4) is particularly preferably a polydimethylsiloxane, a poly (methylphenyl) siloxane or a dimethylsiloxane-diphenylsiloxane copolymer, very particularly preferably a polydimethylsiloxane. The formula (4) is a structural formula, so it also shows the linkage of the siloxane units to one another.

The polymer Pol2 preferably has a weight average molecular weight M _{w of} from 40,000 to 100,000 g / mol, more preferably from 55,000 to 85,000 g / mol.

The polymer Pol2 also preferably has a viscosity of 5 to 40 Pa · s, particularly preferably 10 to 30 Pa.s.

In principle, the polymers Pol1 and Pol2 can be composed of the same or different monomers. The polymer Pol2 is preferably composed of the same monomers as the polymer Poll, although the number of repeating units and therefore the molecular weight may differ.

The composition contains at least one organosilane or organooligosiloxane with at least three Si-bonded groups which can be split off with water. An organosilane is preferably used; it is particularly preferably selected from the group consisting of vinyltrimethoxysilane (VTMO), vinyltriethoxysilane (VTEO), methyltrimethoxysilane (MTMO), methyltriethoxysilane (MTEO), tetraethylorthosilicate (TEOS), tetramethylorthosilicate (methylethylorthosilicate (TMOS), methylethylorthosilicate (TMOS) silane, tetra (methyl ethyl ketoxime) silane, vinyl tris (methyl ethyl ketoxime) silane, methyl tris (methyl isobutyl ketoxime) silane, vinyl tris (methyl isobutyl ketoxime) silane and tetra (methyl isobutyl ketoxime) silane.

The polymer Poll or the entirety of all polymers Pol1 is present in the composition to be mixed, preferably at 10 to 50% by weight, more preferably at 20 to 40% by weight, in each case based on the total weight of the composition.

The polymer Pol 2 or the entirety of all polymers Pol2 is present in the composition to be mixed preferably in an amount of 5 to 30% by weight, more preferably 8 to 20% by weight, based in each case on the total weight of the composition.

The weight ratio of the entirety of all polymers Poll to the entirety of all polymers Pol2 is preferably 5: 1 to 10: 1.

The organosilane or organooligosiloxane or the entirety of all organosilanes and organooligosiloxanes each having at least three Si-bonded groups which can be split off with water is preferably 0.5 to 8% by weight, more preferably 1 to 5% by weight, in the composition to be mixed. -%, each based on the total weight of the composition, before.

The composition is preferably mixed with the exclusion of atmospheric moisture.

The polymer composition according to the invention and the composition to be mixed each comprise at least one condensation catalyst.

The condensation catalyst is preferably selected from the group consisting of tin, titanium, zinc, zirconium, phosphorus and bismuth compounds; in particular selected from the group consisting of organotin, organotitanium, organozinc, organozirconium, organophosphorus and organobismuth compounds.

The total of all condensation catalysts is contained in the polymer composition according to the invention or in the composition to be mixed, preferably 0.05 to 5% by weight, particularly preferably 0.08 to 1% by weight, each based on the total weight of the composition .

The polymer mass according to the invention and the composition to be mixed preferably comprise at least one filler. The filler is particularly preferably selected from the group consisting of CaCO ₃ , pyrogenic silica, precipitated silica, Al (OH) ₃ and BN. In principle, all of the fillers listed can be surface-hydrophobized, in particular with fatty acids, for example stearic acid. The total of all fillers is contained in the polymer composition according to the invention or in the composition to be mixed, preferably at 20 to 80% by weight, particularly preferably at 30 to 60% by weight, in each case based on the total weight of the composition.

In one embodiment, the polymer composition according to the invention comprises at least one chalk. The chalk can be functionalized or unfunctionalized, it can contain one or more chalks. Chalk is preferably contained in the polymer composition according to the invention to a total of at most 60% by weight, based on the total weight of the polymer composition, in particular 20 to 55% by weight.

The polymer composition according to the invention and the composition to be mixed can comprise one or more adhesion promoters. If included, the adhesion promoter is preferably selected from aminopropyltrialkoxysilanes and glycidyloxypropyltrialkoxysilanes; it is particularly preferably selected from aminopropyltriethoxysilane (AMEO) and glycidyloxypropyltriethoxysilane (GLYEO). The total of all adhesion promoters in the polymer composition according to the invention or in the composition to be mixed is preferably 0.1 to 2% by weight, particularly preferably 0.5 to 1.5% by weight, based in each case on the total weight of the composition , contain.

The polymer composition according to the invention can comprise one or more plasticizers. If included, the plasticizer is preferably a trimethylsilyl-terminated polydiorganosiloxane or a mixture of Trimethylsilyl-terminated polydiorganosiloxanes with various chain lengths; it is particularly preferably a trimethylsilyl-terminated PDMS or a mixture of trimethylsilyl-terminated PDMS with different chain lengths.

Another object of the invention is the use of a polymer composition according to the invention for producing permanent bonds, preferably structural bonds, in particular for connecting components in electronic devices, in construction applications, in aircraft construction and / or in automobile construction. The polymer composition according to the invention is particularly preferably used to produce bonds, in particular structural bonds, in glazing, in particular in structural glacing processes.

The invention also provides the use of a polymer composition according to the invention for producing an adhesive tape, preferably for producing an adhesive tape for forming structural bonds.

Examples

Production of a dimensionally stable, reactive silicone adhesive:

The components listed in Table 1 were mixed in the proportions indicated there in a stirrer with exclusion of atmospheric moisture. For this purpose, the polymer and the pigment paste were initially introduced. The mixture was slowly heated to 45-55 ° C. and the mixing room was evacuated. Methyltri (methylethylketoxime) silane, tetraethylorthosilicate and aminopropyltriethoxysilane were then added and mixed under protective gas. Vinyltri (methylethylketoxime) silane was then added under protective gas. In the next step, the chalks were added in portions under protective gas. In the last step, dibutyltin dilaurate was mixed in under protective gas and the mixture was filled into cartridges with the exclusion of air. Table 1: Composition of the mixture for producing the silicone adhesive Polydimethylsiloxane (PDMS) hydroxy-terminated on both sides (Mw = 100,000 g / mol, η = 80 Pa s) 31.62% Methyl tri (methyl ethyl ketoxime) silane 2.91% Tetraethyl orthosilicate 0.45% Vinyl tri (methyl ethyl ketoxime) silane 1.04% Aminopropyltriethoxysilane 1.29% Pigment (carbon black dispersed in PDMS oil, Wacker ELASTOSIL color paste 9005 black) 5.25% untreated chalk 44.67% chalk treated with fatty acid 12.76% Dibutyltin dilaurate 0.01%

The mixture produced in this way (hereinafter referred to as M1) was mixed with a double-sided hydroxy-terminated PDMS (Mw = 70,000 g / mol, η = 20 Pa · s) in a weight ratio of M1: PDMS of 7.5: 1 with further exclusion of atmospheric moisture and after 6 hours formed into a web with a layer thickness (hereinafter also referred to as "layer body") specified in the following measurements. The mass to be shaped into the web resulting from the mixing of the mass M1 with the further PDMS described here is referred to below as M2.

Gel Permeation Chromatography (GPC):

The number and weight average molecular weights (M _n and M _w ) of the organopolysiloxanes and silicone resins used can be determined using GPC. The following settings were used for the determination: eluent toluene; Measuring temperature 23 ° C; Guard column PSS-SDV, 5 µm, 10 ² Å (10 nm), ID 8.0 mm x 50 mm; Separation: PSS-SDV columns, 5 µm, 10 ² Å (10 nm), as well as 10 ³ Å (100 nm), and 10 ⁶ Å (10 ⁵ nm), each with ID 8.0mm x 300mm; Sample concentration 3 g / l, flow rate 1.0 ml per minute; Polydimethylsiloxane standard (14-point calibration in the MPeak range from 400 to 2,300,000 g / mol).

Dimensional stability:

Example Dim1

The mass M2 produced as described above was formed on a 120 μm thick HDPE film in two 10 × 20 cm frames to form two laminates, each 1 mm thick. The frames were removed and the laminates covered with another 120 µm HDPE film. The composite formed in this way was welded airtight together with a silica drying medium in a moisture-proof aluminum / PE composite bag and stored at room temperature.

After two days the first layer body was removed from the aluminum / PE composite bag, after 7 days the second. The HPDE films could be peeled off without residue from both layers.

Comparative example Dim2

Analogous to Example Dim1, a 1 mm thick layer body was produced from the mixture M1 and welded airtight into a moisture-proof aluminum / PE composite bag without adding a hydroxy-terminated PDMS, but otherwise analogously to Example Dim1 together with the drying medium.

After two days the first layer body was removed from the aluminum / PE composite bag, after 7 days the second. Both laminates were split into (cohesively) when the film was peeled off.

T-block test:

• Zwei Aluminiumprofile in T-Form (25 x 25 x 2 mm, 25 mm) wurden mit Aceton gereinigt, woraufhin das Lösemittel 10 min abdampfen konnte. Der Schichtkörper wurde zu quadratischen Abschnitten mit einer Kantenlänge von 25 mm zugeschnitten. Anschließend wurden die Aluminiumprofile mit jeweils einem Schichtkörper verklebt und für 15 s mit der Hand verpresst. Der so hergestellte Prüfling wurde dann für den in Tabelle 2 angegebenen Zeitraum bei 23 °C und 50 % relativer Luftfeuchtigkeit äquilibriert. Anschließend wurde der Prüfling in eine Zugprüfmaschine der Firma ZWICK eingespannt, woraufhin die beiden T-Blöcke mit einer Geschwindigkeit von 50 mm/min auseinandergezogen wurden. Die dazu benötigte Maximalkraft wurde gemessen, als Ergebnis wird in Tabelle 2 der Mittelwert aus zwei Einzelmessungen in kPa angegeben.

Tabelle 2: Ergebnisse des T-Block-Tests Lagerzeit bei Normklima Maximalkraft [kPa] 1 Woche 522 2 Wochen 765 4 Wochen 880 As described in Example Dim1, a layered body with two outer HDPE films was produced from the mass M2, which, together with a drying medium, was welded airtight into a moisture-proof aluminum / PE composite bag. After 2 days, the laminated body was removed from the aluminum / PE composite bag. After the films had been peeled off, the laminate was subjected to the following test:

• Two T-shaped aluminum profiles (25 x 25 x 2 mm, 25 mm) were cleaned with acetone, after which the solvent was allowed to evaporate for 10 minutes. The laminate was cut into square sections with an edge length of 25 mm. The aluminum profiles were then glued to a laminate each and pressed by hand for 15 s. The test specimen produced in this way was then equilibrated at 23 ° C. and 50% relative humidity for the period indicated in Table 2. The test specimen was then clamped in a tensile testing machine from ZWICK, whereupon the two T-blocks were pulled apart at a speed of 50 mm / min. The maximum force required for this was measured, and the result in Table 2 is the mean value of two individual measurements in kPa.

Table 2: Results of the T-block test Storage time at standard climate Maximum force [kPa] 1 week 522 2 weeks 765 4 weeks 880

The increasing force required to separate the T-profiles with prolonged storage indicates a progressive increase in the cohesion of the mass under the influence of moisture and thus the reactivity of the dimensionally stable silicone adhesive according to the invention.

The mass M1 could not be introduced into this test at all as a laminate used for gluing the T-profiles, since it was not dimensionally stable and ran between the profiles. A meaningful execution of the test was not possible.

Rheological measurements:

The rheological parameters of the masses to be examined were determined on a Rubber Process Analyzer RPA2000 from Alpha. The measurements were carried out for 10 minutes at 30 ° C. with a frequency of 10 rad / s and a deflection of 4%.

Example according to the invention

Analogously to Example Dim1, two laminates, each 2 mm thick, were formed between two 50 μm PET films from the mass M2. One of these laminated bodies was welded together with a silica drying medium in a moisture-proof aluminum / PE composite bag and stored in it for two days at room temperature. The second layer body was stored for four weeks in a standard climate for complete hardening.

Comparative example

The rheological parameters of the mass M1 were determined as a comparative example.

Analogous to Dim1, two laminated bodies, each 2 mm thick, were also formed from this mass between two PET films and packed or stored as described above. Table 1: Results of the rheological investigations parameter conditions M2 M1 (cf.) Complex viscosity [Pa · s] Shrink-wrapped for 2 days 1,680 700 After 4 weeks of normal climate 36,320 42,650 Loss factor (tanD) Shrink-wrapped for 2 days 0.77 1.42 After 4 weeks of normal climate 0.19 0.24

The rheological parameters determined in accordance with Table 1 show that the viscosity of the silicone adhesive according to the invention increases on storage under the influence of air. The loss factor is <1 and decreases further under the influence of humidity. The composition according to the invention thus resembles an elastic body rather than a liquid in its behavior.

The viscosity of the mass M1 in the comparative example also increases further when it is stored under the influence of air. The loss factor is well above 1 with the exclusion of atmospheric moisture and only drops below 1 after exposure to moisture. The behavior of the mass M1 with the exclusion of atmospheric moisture and initially after such storage is therefore more like a liquid than an elastic body.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was 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.

Patent literature cited

• EP 1396513 A1 [0005]
• WO 2011/051385 A2 [0006]
• WO 2009/130298 A1 [0008]
• WO 2012/119940 A1 [0015]
• WO 2014/086638 A1 [0016]
• WO 2007/009871 A2 [0018]

Non-patent literature cited

• DIN 53019 [0044]

Claims (7)

Chemically pre-crosslinked and further crosslinkable with moisture, auto-adhesive polymer composition for use as a layered body which can be applied to a substrate, the polymer composition at least one polymer having at least two terminal silyl groups according to the formula (1) Si (R ¹ ) _a (R ² ) _b (1), in which the radicals R ¹ independently of one another represent an alkyl, alkenyl or aryl group or a hydrogen atom, the radicals R ^{2 represent} a group which can be split off with water and b = 1, 2 or 3 and a = 3 - b; and comprises at least one condensation catalyst. Polymer mass according to Claim 1 , characterized in that the radicals R ² according to the formula (1) are selected from the group consisting of alkoxy, acyloxy, amino, enoxy and ketoxime groups. Polymer composition according to one of the preceding claims, obtainable by mixing a composition comprising: - At least one polymer Poll, the termini of which are each formed independently of one another by a silyl group according to the formula (1), - At least one polymer Pol2, which has at least two terminal, Si-bonded OH groups; - At least one organosilane and / or at least one organooligosiloxane, each containing at least three Si-bonded groups which can be split off with water; and - At least one condensation catalyst. Polymer mass according to Claim 3 characterized in that all of the Poll polymers are present in the composition at 10 to 50% by weight based on the total weight of the composition. Polymer composition according to one of the Claims 3 and 4th , characterized in that all of the Pol2 polymers are present in the composition at 5 to 30% by weight, based on the total weight of the composition. Polymer composition according to one of the preceding claims, characterized in that the condensation catalyst is selected from the group consisting of tin, titanium, zinc, zirconium, phosphorus and bismuth compounds. Use of a polymer composition according to one of the Claims 1 to 6th for the production of permanent bonds.