EP4263187A1

EP4263187A1 - Decoupling bushing on the basis of a cast elastomer

Info

Publication number: EP4263187A1
Application number: EP21843589.9A
Authority: EP
Inventors: Maximilian Maier; Johannes Poppenberg; Andreas Horstmann; Ann-Christin COLLMOOR; Marc Ingelmann; Ulrich Holwitt; Sabrina ENGEL
Original assignee: BASF Polyurethanes GmbH
Current assignee: BASF Polyurethanes GmbH
Priority date: 2020-12-18
Filing date: 2021-12-10
Publication date: 2023-10-25
Also published as: WO2022128825A1

Abstract

The present invention relates to a bearing for vibration damping (i), comprising: a bushing (ii), which surrounds a cavity (iii); and a fastening element (iv), which is located in this cavity (iii); wherein a compact polyurethane elastomer preparation (v) is located in the cavity and connects the external bushing (ii) to the fastening element (iv), and the polyurethane elastomer in the polyurethane elastomer preparation (v) is the reaction product of the structural components diisocyanate, a polyester diol, a polyether diol, or a mixture thereof, and a chain extender, and the preparation optionally also contains at least one of the following components: catalyst auxiliary and additive. The invention also relates to producing a corresponding bearing.

Description

Decoupling bushing based on a cast elastomer

The subject matter of the present patent application is a bearing that is used for vibration damping or vibration decoupling.

Such camps have been described many times. Rubber, in particular based on natural rubber, is predominantly used as the damping material. In addition, bearings made of microcellular polyurethane are known, which have excellent damping properties when mounting chassis and drive train components, but have a low stiffness spread in the different spatial directions due to the microcellular structure, and therefore often do not meet driving dynamics requirements, especially in the chassis area. Corresponding bearings are described, for example, in WO 03/104 326, WO 03/104 345, WO 03/1046766, WO 03/1046767, DE 10 2004 056 548 or also WO 2008/058914. DE 102 25 797 A1 discloses DE 102 25 797 A1 discloses a round bearing with a bearing element based on cellular polyisocyanate polyaddition products, in which the adhesion between the bearing element and the inner bushing takes place with thermoplastic polyurethane.

In addition, bearings for the aftermarket made of compact polyurethane are known, which have the goal of a sportier tuning of the vehicle and a long service life due to a high material hardness and thus a high bushing rigidity, but no longer meet the original requirements for vibration damping or decoupling.

With the increasing use of electric motors, in particular also as a drive in the field of automobiles, completely new requirement profiles are placed on the bearings with regard to vibration damping or vibration decoupling. However, the ability of rubber mounts to decouple vibrations is heavily dependent on the hardness of the rubber compound. Low hardnesses in the range of 35-45 Shore A can ensure good vibration decoupling, but are often too soft for the additional driving dynamics requirements, especially when using the bearings in the chassis area, so that rubber mixtures with hardnesses > Shore 60 A often have to be used , the production of which is very demanding on the one hand and which, moreover, only inadequately fulfill high-frequency vibration decoupling.

The present invention was therefore based on the task of developing a mount for vibration damping or vibration decoupling, which can also meet the increased requirements of the vibrations generated by electric motors up to a high frequency range and at the same time meet driving dynamics requirements.

7 figures is easy to manufacture, can be designed so that the resilience is different in different spatial directions and still has a sufficiently high operational strength.

Surprisingly, it was found that this problem could be solved with a bearing having the features according to claim 1 .

A further object of this invention is the production of such a bearing according to claim 14 and the use of a polyurethane elastomer preparation (v) for the production of the bearing according to the invention.

Characters:

Figure 1 shows a preferred embodiment of a bearing (i) having an outer sleeve (ii) surrounding a cavity (iii) and a fastener (iv) located in this cavity

(iii) located. The compact polyurethane elastomer composition (v) is introduced into the cavity (iii) which in the finished bearing connects the outer bushing (ii) to the fastening element (iv) (see also the following figures 2 and 3).

FIG. 2 shows a preferred embodiment of a bearing (i), in FIG. 2a) in an oblique top view, in FIG. 2b in top view, and in FIG. 2c in a side view. The bearing (i) has an outer sleeve (ii) surrounding a cavity (iii) and a fastener (iv) located in this cavity (iii). Also in the cavity (iii) is the compact polyurethane elastomer composition (v) containing the outer bushing (ii) with the fastener

(iv) connects, wherein the polyurethane elastomer preparation (v) contains two continuous recesses (vi).

FIG. 3 shows a preferred embodiment of a bearing (i), in FIG. 3a) in an oblique top view, in FIG. 3b) in a top view, and in FIG. 3c) in a side view. The bearing (i) has an outer sleeve (ii) surrounding a cavity (iii) and a fastener (iv) located in this cavity (iii). Also in the cavity (iii) is the compact polyurethane elastomeric formulation (v) connecting the outer bushing (ii) to the fastener (iv), the polyurethane elastomeric formulation (v) containing two through recesses (vi) and two partially through recesses (vii). .

FIG. 4 shows an arrangement for testing the bearing (i), which is pressed into a bearing mount (viii) which is connected to a testing machine (x) via the holder (ix). A force F acts on the fastening element (iv) of the bearing via the test device (xi). FIG. 4a shows a force acting on the bearing in the radial direction, and in FIG. 4b) in the axial direction. FIG. 5 shows the force-displacement curves and the stiffness-displacement curves of a bearing according to FIG. 2 and recipe 6 with the quasi-static load according to example 2a. The force F is plotted on the left vertical axis with the unit [kN], the stiffness Cs with the unit [kN/mm] on the right vertical axis and the displacement s with the unit [mm] on the horizontal axis, each in the axis directions of the bearing, x-axis (Figure 5a), y-axis (Figure 5b) and z-axis (Figure 5c). The bearing stiffness Cs is calculated from the local slope of the force-displacement curve.

FIG. 6 shows the course of the bearing stiffness Cd and the bearing damping D over the frequency of the applied vibration f with a dynamic load on a bearing of a bearing according to FIG. 2 and recipe 6 under a defined initial load. The bearing stiffness Cd is plotted with the unit [kN/mm] on the left vertical axis, the bearing damping D with the unit [°] on the right vertical axis and the frequency f with the unit [Hz] on the horizontal axis. Figure 6a shows the bearing stiffness and bearing damping in the x-axis direction under the preload OkN, Figure 6b shows the bearing stiffness and bearing damping in the y-axis direction under the preload OkN and Figure 6c shows the bearing stiffness and bearing damping in the z-axis direction under the preload of 1 kN.

The bearing stiffness c _{d is} calculated from the slope of the force-displacement curve for a sinusoidal excitation with an excitation amplitude of 0.1 mm. The bearing damping D is represented as a loss angle, which indicates the phase shift of the output signal (force amplitude) compared to the input signal (displacement amplitude) with a sinusoidal excitation with an excitation amplitude of 0.1mm. The frequency f represents the number of sinusoidal excitations per second.

Detailed description

An object of the invention in an embodiment 1 is a bearing for vibration decoupling (i) comprising a bushing (ii) surrounding a cavity (iii) and a fastener (iv) located in this cavity (iii) wherein in the cavity is a compact polyurethane elastomer composition (v) which connects the outer bush (ii) to the fastener (iv), characterized in that

Polyurethane elastomer (v) in the formulation is the reaction product of the following structural components a. a diisocyanate b. a polyester diol, a polyether diol, or a mixture thereof c. a chain extender and the preparation optionally contains at least one of the following components d. catalyst e. excipient, and/or f. additive

The compact polyurethane elastomer preparation (v) preferably has a density between 0.8 g/l and 1.5 g/l, preferably between 0.9 g/l and 1.4 g/l and in particular between 1 g/l and 1. 3g/L.

Surface treatment:

In a preferred embodiment 2, incorporating all the features of the previous embodiment or one of its preferred embodiments, the surface of the bushing (ii) or the surface of the fastener (iv) bonded to the polyurethane elastomer composition, or both surfaces is surface treated. This improves the adhesion of the polyurethane elastomer preparation (v) to the respective surface. The surfaces are preferably swollen, pickled, ground, blasted, treated with electromagnetic radiation, with a plasma, or with a combination of these methods. Blasting is preferred, with the surface preferably being blasted with a hard medium, preferably corundum or steel shot. The surfaces are preferably additionally or alternatively treated with electromagnetic radiation. A preferred supplementary or alternative surface treatment is treatment with a plasma, preferably a low-pressure or atmospheric plasma. Organic coating precursor compounds can preferably be fed into the plasma and then deposited as a plasma-polymeric layer. Corresponding methods are known and described (e.g. DE 10 2017 201 559 A1).

In the case of plastics, the surface treatment is preferably also carried out by an oxidizing treatment, for example by flame treatment or gas-phase fluorination.

In the case of metals, the surface treatment is preferably carried out by roughening via blasting with hard media or by building up a defined conversion layer, e.g. a trication zinc phosphating according to WO 2019/215 119.

adhesion promoter:

In a preferred embodiment 3, incorporating all features of any of the preceding embodiments or one of their preferred embodiments, is the surface of the bushing (ii) or the surface of the fastener (iv) bonded to the polyurethane elastomer composition (v), or both surfaces with a Adhesion promoter provided. The adhesion promoter improves the connection between the polyurethane elastomer preparation (v) and the corresponding surface.

An adhesion promoter tailored to the corresponding polyurethane elastomer preparation (v) is preferably used.

So that adhesion promoters can have an optimal effect, the substrate surfaces must be clean, preferably have an enlarged surface, and more preferably be sufficiently reactive, which is why a surface treatment as described above is preferably carried out before the adhesion promoter is applied. Carboxy groups or OH groups are preferably required for the reaction with adhesion promoters. OH groups can be found on practically all base metals because they form an oxide layer in the atmosphere. Particularly good adhesion bases can be produced by prior coating with silicon dioxide, preferably by physical vapor deposition (PVD), chemical vapor deposition (CVD) or flame coating. The latter can also be used with plastics.

Modified polyolefins

Preferred adhesion promoters for plastics are modified polyolefins. To this end, a polyolefin is preferably modified in such a way that the previously insoluble polyolefin is soluble in organic solvents. Chlorine, acrylic acid derivatives or maleic anhydride are preferably used for the modification. With chlorine, so-called chlorinated polyolefins (CPO) are formed.

silane coupling agent

Silane coupling agents are preferably used on metal surfaces. For this purpose, a silicon dioxide layer is applied to the metal surface.

Alternatively, the silane adhesion promoters used can also react directly with the chemical groups on the surface, with the condensation reaction then taking place with elimination of the alcohol or HCl. The organic group of the silane allows attachment to the polyurethane elastomer.

Adhesion promoters of the general form R—SiX3 are preferably applied to this silicon dioxide layer. R is preferably an organically functionalized radical and X is a hydrolyzable group, preferably an alkoxy group or --Cl, the alkoxy group being particularly preferred. Through hydrolysis reactions with water, they form silanols of the form R-Si(OH)3. With inorganic materials that have OH or COOH groups on the surface, silanols can enter into condensation reactions and thus form a stable compound through chemical bonds.

The organic group R preferably consists of a spacer and a functional group. The spacer is preferably an alkyl radical, which more preferably contains between 2 and 6 carbon atoms, more preferably is unbranched. The spacer is particularly preferably a propyl chain. Preferred functional groups are vinyl, methacrylic acid, epoxy, amino, urea or thiol groups, particularly preferred are amino, urea or thiol groups.

In another preferred embodiment, adhesion promoters are reactive or non-reactive mixtures of organic solvents and organic monomers, oligomers, or polymers. In a preferred embodiment, the adhesion promoters are based on phenolic resins. Solvents in which the phenolic resins are preferably dissolved are selected from the group of butanone, toluene, xylene, 2-methoxy-1-methylethyl acetate, ethyl-3-ethoxypropinate, or are mixtures thereof

In a further preferred embodiment 4, which contains all the features of one of the preceding embodiments or one of their preferred embodiments, the adhesion promoter is present in a 5 μm to 50 μm thick layer between the polyurethane elastomer preparation (v) and the corresponding surface, the layer being preferred 10 pm to 30 pm thick.

In a further preferred embodiment 5, which contains all the features of one of the preceding embodiments or one of their preferred embodiments, the adhesion promoter has a free surface energy according to drop shape analysis of more than 35 mN/m, with polar components of less than 15 mN/m, particularly preferred the polar components are less than 5 mN/m. The determination is carried out according to DIN 55660-2 from December 2011.

In a further preferred embodiment 6 according to one of the preceding embodiments or one of their preferred embodiments, the adhesion promoter is a polymer whose glass transition temperature (DSC) is below 100°C, more preferably below 60°C.

In a further preferred embodiment 7 according to one of the preceding embodiments or one of their preferred embodiments, the adhesion promoter is a cationic dip paint (KTL), which is also referred to as a cathodic dip paint. A preferred dip coating is described in WO 2019/215119, for example. Details of this description form part of this disclosure.

geometries

The bearing consists of at least three essential elements, an external bushing (ii), which spans a cavity (iii) in which the fastening element (iv) is located. The fastener (iv) is bonded to the outer bushing (ii) via the polyurethane elastomer composition (v). Basically, the design of the warehouse is adapted to the specific structural conditions and requirements of the warehouse. Some bearings are preferably axisymmetric to the axis of the fastening element (iv), other preferred bearings do not have an axisymmetric structure. The non-axisymmetric structure has the advantage that different decoupling properties and damping properties can be realized in the bearing in different spatial directions. Individual preferred embodiments of the bearing design can be found in the figures.

Polyurethane preparation / use

The polyurethane elastomer preparation (v) must be designed in such a way that on the one hand it bears the load of the bearing and at the same time also makes a significant contribution to vibration decoupling, in some embodiments also to vibration damping by the bearing. The bearing according to one of the previous embodiments or one of its preferred embodiments is preferably intended for the storage of units that cause vibrations, in particular the units are electric motors. The units are connected to the bearing directly or via a frame. The frame is preferably an auxiliary frame. A subframe is a frame that is used to hold the unit, preferably the electric motor. The subframe and unit can in turn be part of a larger device. This subframe is more preferably part of a vehicle, in particular a vehicle powered by an electric motor, in particular a car.

The vibration decoupling or vibration damping is determined on the one hand by the composition of the ingredients of the polyurethane elastomer preparation (v) and on the other hand by its spatial configuration.

In preferred embodiments, the strength of the polyurethane preparation (v) varies in strength in different spatial axes between the outer bushing (ii) and the fastening element (iv). In other preferred embodiments, different decoupling properties or damping properties are achieved by different ingredients of the polyurethane elastomer preparation (v). In still other preferred embodiments, parts of the cavity (iii) are not filled with the polyurethane elastomer preparation (v). In other preferred embodiments, these continuous cutouts (vi) or partially continuous cutouts (vii) are completely or partially filled with other damping or decoupling materials. A preferred such material is microcellular polyurethane (Cellasto®). It has been described many times and is tailored to the special decoupling and damping requirements within the bearing. Preferred embodiments are set out in the text.

Preferred bearings include either one of these configurations or combinations of two or more of these configurations.

For good vibration damping or vibration decoupling, it is important that the polyurethane elastomer preparation (v), possibly also others for damping, is in the cavity materials are dimensioned in such a way that they can move freely when used as intended, in order to be able to fully develop their vibration-decoupling or vibration-damping properties. In other words, they are dimensioned in such a way that they do not come into contact with any other component apart from the outer bushing (ii) and the fastening element (iv).

In a preferred embodiment 8 of the bearing according to one of the preceding embodiments or one of its preferred embodiments, the polyurethane elastomer preparation (v) contains voids. In cases in which the fastening element (iv) or the bushing (ii) has a, preferably at least essentially, axisymmetric structure, the polyurethane elastomer preparation (v) contains two or more continuous or partially continuous recesses parallel to at least one of these axes different cross section. In each case, two recesses in the polyurethane elastomer preparation (v) preferably lie opposite one another axially symmetrically with respect to the fastening element (iv). This has the advantage, among other things, that they can be manufactured more easily. Other preferred bearings do not have an axisymmetric structure. The non-axisymmetric design has the advantage that different decoupling properties and damping properties can be realized in the bearing in different spatial directions.

In a preferred embodiment 9 of the bearing according to the preceding embodiment or one of its preferred embodiments, at least one of the recesses at least partly contains microcellular polyurethane.

In a preferred embodiment 10 of the bearing according to one of the preceding embodiments or one of its preferred embodiments, a region of the cavity (iii) spanning between the bushing (ii) and the fastening element (iv) is in the direction of the z-axis above or below, or above and below the polyurethane elastomer preparation (v) completely or partially filled with microcellular polyurethane.

Rifle

The outer geometry of the bushing (ii), ie the side facing away from the polyurethane elastomer preparation (v), is designed in such a way that it can be easily manufactured and at the same time can be easily inserted into the intended installation space. In a preferred embodiment 11 of the bearing, according to one of the preceding embodiments or one of its preferred embodiments, the outer contour of the outer sleeve is therefore a cylinder. preferred the socket on one side has a collar that runs around or partially around the y-axis. This collar makes it possible to limit the penetration depth of the bearing into the bearing seat, also known as the installation space. The bushing (ii) is preferably shaped on the outside in such a way that it can be introduced into the installation space with a form fit. A preferred type of form fit is a thread. Another preferred type of form fit is an undercut via latching lugs. In another preferred embodiment, the bushing is oversized relative to the installation space, so that it can be pressed into the installation space for a tight fit. The contour of the inside of the bushing (ii), ie the surface of the bushing (ii) facing the polyurethane elastomer preparation (v) and at least partially in contact with it, is optimized on the one hand for manufacturing reasons. On the other hand, the surface is preferably designed in such a way that good contact is possible at least with the polyurethane elastomer preparation (v), optionally also with other decoupling materials, preferably microcellular polyurethane. Furthermore, the surface is preferably designed in such a way that, in conjunction with the polyurethane elastomer preparation (v), good vibration decoupling, possibly also vibration damping, is achieved with high load capacity. In preferred embodiments, the inside of the sleeve is at least partially the surface of a cylinder or at least partially that of an ellipse. Other exemplary and preferred embodiments can be found in the figures.

In a preferred embodiment 11 of the bearing according to one of the preceding embodiments or one of its preferred embodiments, the bushing (ii) consists of a metal or a plastic. The metal is preferably aluminum or an aluminum alloy. The bushing (ii) preferably consists of a plastic. The plastic is preferably reinforced with glass fiber. The glass fiber content is preferably 10% by weight to 70% by weight, based on the plastic, preferably between 15% by weight and 50% by weight, more preferably between 20% by weight and 40% by weight , more preferably between 25% and 35% by weight and most preferably at 30% by weight. The plastic is preferably a polyamide, particularly preferably a [6,6]-polyamide.

The fastening element (iv), which is located in the cavity (iii) of the bearing, is designed in such a way that it is itself designed as a fastening means or enables the bearing to be fastened using conventional fastening means.

The contour of the outside of the fastening element (iv), ie the surface of the fastening element (iv) facing the polyurethane elastomer preparation (v) and at least partially in contact with it, is preferably optimized on the one hand for production reasons, on the other hand the surface is preferably designed in such a way that good contact is achieved at least with the polyurethane preparation (v), optionally further decoupling materials possible is. Furthermore, the surface is preferably designed in such a way that, in conjunction with the elastomer preparation (v), good vibration decoupling, possibly also vibration damping, is achieved with a high load capacity. In preferred embodiments, the outside of the fastening element (iv) is at least partly the surface of a cylinder or at least partly that of an ellipse.

In a preferred embodiment 12 of the bearing according to one of the preceding embodiments or one of its preferred embodiments, the fastening element (iv) or the bushing (ii) or the fastening element (iv) and the bushing (ii) is coaxial. The arrangement of the bush (ii) and the fastener (iv) are coaxial with each other also in the bearing only in some embodiments. In other embodiments, the axes are not congruent in order to allow non-uniform thicknesses of the polyurethane elastomer preparation (v) in the different spatial directions.

In a preferred embodiment 13 of the bearing according to one of the preceding embodiments or one of its preferred embodiments, the fastening element (iv) is internally hollow.

The internal contour of the fastening element (iv), which is hollow on the inside, i.e. the side facing away from the polyurethane elastomer preparation (v), is designed in such a way that it can be easily manufactured and at the same time can be easily fastened in the intended installation space using the usual fastening means.

In a preferred embodiment 14 of the bearing according to one of the preceding embodiments or one of its preferred embodiments, the fastening element consists of a metal, preferably aluminum or an aluminum alloy. More preferably, the metal is at least partially, preferably entirely, encased in a plastic. The plastic is preferably glass fiber reinforced. The plastic is more preferably polyamide, in particular glass fiber reinforced polyamide, preferably as described above for the socket.

In a preferred embodiment 15 of the bearing according to one of the preceding embodiments or one of its preferred embodiments, the inner contour of the fastening element is a cylinder. The fastening element (iv) is preferably shaped on the inside in such a way that it can be fastened in a form-fitting manner, preferably by means of a thread. In other preferred embodiments, the fastening element (iv) is internally shaped in such a way that conventional fastening means, such as screws or threaded bolts, can be passed through. In this way, the fastening element can be screwed to the installation space via the fastening element. In another preferred embodiment, the inner opening of the fastener has an undersize compared to the fastener, so that it can be pressed in with the latter for a tight fit on the fastener.

Two preferred embodiments of a bearing according to the invention are shown in FIGS.

polyurethane elastomer formulation

The composition of the polyurethane elastomer preparation (v), which is located in the cavity between the outer bushing (II) and the fastening element (iv) and at least partially fills it, is adapted to the specific requirements of the bearing, such as hardness and damping. Together with the specific contouring of the polyurethane elastomer preparation (v), this allows the static and dynamic flexibility of the bearing to be adjusted in the various spatial directions.

The components (a) isocyanate, (b) isocyanate-reactive compounds and (c) chain extenders are also addressed individually or together as structural components. The structural components including the catalyst and/or the customary auxiliaries and/or additives are also referred to as starting materials.

Polyol of polyurethane elastomer

In a preferred embodiment 16 of the bearing according to any one of the preceding embodiments or one of its preferred embodiments, the polyester diol and the polyether diol in the polyurethane elastomer composition (v) is linear. More preferably, the monomers that form the polyester diol or the polyether diol comprise between 4 and 20 carbon atoms, more preferably 4 to 10 carbon atoms, more preferably 4 to 7 carbon atoms. The monomers are also preferably linear. The polyether diol is particularly preferably polytetrahydrofuran (PTHF) and the polyester diol is polycaprolactone.

In a preferred embodiment 17 of the bearing according to one of the preceding embodiments or one of its preferred embodiments, the number average molecular weight of the polyester diol and the polyether diol is between 0.5 x 10 ³ g/mol and 5 x 10 ³ g/mol, preferably between 0.8 x 10 ³ g/mole and 3 x 10 ³ g/mole.

In a preferred embodiment 18 of the bearing according to one of the preceding embodiments or one of its preferred embodiments, the structural components are diisocyanate, polytetrahydrofuran, preferably according to the preferences mentioned above, and chain extenders. The polytetrahydrofuran (PTHF) is more preferably a mixture of two polytetrahydrofurans PTHF 1 and PTHF 2. The number-average molecular weight of PTHF 1 is preferably between 0.5×10 ³ g/mol and 1.5×10 ³ g/mol, particularly preferably 1×10 ³ g/mol and at the same time the number-average molecular weight of PTHF 2 is between 1.5×10 ³ g/mol and 2.5×10 ³ g/mol, particularly preferably 2×10 ³ g/mol . More preferably, the weight ratio of PTHF 1 to PTHF 2 is between 1:100 and 100:1, preferably between 20:80 and 80:20, more preferably between 40:60 and 60:40, more preferably between 45:55 and 55 45, and most preferably 50/50.

isocyanates

In principle, any isocyanate can be used for the bearing according to the invention, but preference is given to organic isocyanates, more preferably aromatic isocyanates and in particular diisocyanates. Among other things, the latter are easier to process.

In a preferred embodiment 19 of the bearing according to one of the preceding embodiments or their preferred embodiment, the diisocyanate is an aromatic diisocyanate, more preferably selected from the group 2,2'-, 2,4'- and/or 4,4'-diphenylmethane diisocyanate (MDI), 1,5-naphthylene diisocyanate (NDI), 2,4- and/or 2,6-toluylene diisocyanate (TDI), 2,4-tetramethylenexylene diisocyanate (TMXDI), 3,3'-dimethyldiphenyl diisocyanate, 1 ,2-diphenylethane diisocyanate, and p-phenylene diisocyanate (PPDI), or a mixture thereof. More preferably, the isocyanate is 1,5-naphthylene diisocyanate (NDI) or 2,2'-, 2,4'- and/or 4,4'-diphenylmethane diisocyanate (MDI), or a mixture thereof.

In a preferred embodiment of the bearing according to any of the preceding embodiments or their preferred embodiment, the diisocyanate is 2,2'-, 2,4'- and/or 4,4'-diphenylmethane diisocyanate (MDI).

The isocyanates are preferably used in the form of the pure compound, in mixtures and/or in modified form. Preferred modifications, which are preferably used in addition to the isocyanate used, are uretdiones, isocyanurates, allophanates or biurets or mixtures thereof.

The diisocyanate is preferably also used in a mixture with its derivatives. The preferred diphenylmethane diisocyanate (MDI) particularly preferably contains up to 10% by weight, more particularly preferably up to 5% by weight, of carbodiimide-, uretdione-, allophanate- or uretonimine-modified diphenylmethane diisocyanate, in particular carbodiimide-modified diphenylmethane diisocyanate. In addition to 2,4'-MDI and 4,4'-MDI, preference is given to using only difunctional isocyanates. The proportion of 2,4′-MDI and 4,4′-MDI in the isocyanate is preferably greater than 60% by weight, particularly preferably greater than 80% by weight and in particular greater than 98% by weight, based on the total used isocyanate. In a preferred embodiment 21 of the bearing according to one of the preceding embodiments or their preferred embodiments, the polyurethane elastomer preparation (v) further contains a carbodiimide, which is preferably based on a diisocyanate, or a uretonimine, which is preferably based on a diisocyanate. In a preferred embodiment, the carbodiimide or the uretonimine is based on the diisocyanate used as a structural component in the polyurethane elastomer. The carbodiimide is preferably present at 0.1 to 10% by weight in the polyurethane elastomer preparation (v). Details on the carbodiimide and its preparation can also be found in US 2007 021 349 6, the content of which is part of the disclosure of this application. In addition to the carbodiimide, the uretonimine is preferably present at 0.01 to 5% by weight in the polyurethane elastomer composition (v).

In a preferred embodiment 22 of the bearing according to one of the preceding embodiments or their preferred embodiments, the chain extender is selected from the group consisting of propanediol, butanediol, pentanediol, hexanediol, hydroquinone bis (2-hydroxyethyl) ether (HQEE) and 1,3-bis (2 -hydroxyethyl)resorcinol (HER), or is a mixture thereof. A particularly preferred chain extender is 1,4-butanediol.

In addition to the structural components of the polyurethane elastomer preparation (v), preferred embodiments of the polyurethane elastomer preparation (v) also contain a catalyst and auxiliaries or additives.

In addition to the separately listed catalyst, the auxiliaries and additives include surface-active substances, foam stabilizers, cell regulators, other release agents, fillers, dyes, pigments, hydrolysis inhibitors, odor-absorbing substances and fungistatic and/or bacteriostatic substances.

catalyst

The catalyst used is preferably a compound which accelerates the reaction of the isocyanate-reactive compound with the isocyanate. Preferred examples are amidines such as 2,3-dimethyl-3,4,5,6-tetrahydropyrimidine, tertiary amines such as triethylamine, tributylamine, dimethylbenzylamine, N-methyl-, N-ethyl-, N-cyclohexylmorpholine, N,N, N',N'-Tetramethylethylenediamine, N,N,N',N'-Tetramethylbutanediamine, N,N,N',N'-Tetramethylhexanediamine, Diazabicycloundecene, Pentamethyldiethylenetriamine, Tetramethyldiaminoethylether, Diazabicycloundecene (DBU), Bis-( dimethylaminopropyl)urea, dimethylpiperazine, 1,2-dimethylimidazole, 1-azabicyclo-(3,3,0)-octane and preferably 1,4-diazabicyclo-(2,2,2)-octane and alkanolamine compounds such as triethanolamine, triisopropanolamine, N-methyl- and N-ethyl-diethanolamine and dimethylethanolamine. Other preferred catalysts mentioned by way of example are organic metal compounds, preferably organic tin compounds, such as tin(II) salts of organic carboxylic acids, eg tin(II) acetate, tin(II) octoate, tin(II) ethyl hexoate and tin (II) laurate and the dialkyltin (IV) salts of organic carboxylic acids, eg dibutyltin diacetate, dibutyltin dilaurate, dibutyltin maleate and dioctyltin diacetate, and bismuth carboxylates such as bismuth (III) neodecanoate, bismuth 2-ethylhexanoate and bismuth -octanoate or mixtures thereof.

1,4-diaza-bicyclo-(2,2,2)-octane (DABCO) and diaza-bicycloundecene (DBU) or mixtures thereof are preferably used as catalysts, mixtures thereof being very particularly preferred.

The diazabicycloundecene bicycloundecene (DBU) is preferably 1,8-diazabicyclo[5.4.0]undec-7-ene, more preferably heat-activatable 1,8-diazabicyclo[5.4.0]undec-7-ene and particularly preferably one Phenol-blocked heat-activatable 1,8-diaza-bicyclo[5.4.0]undec-7-ene.

The organic metal compounds are preferably used alone or, in another preferred embodiment, in combination with strongly basic amines.

Suitable surface-active substances are, for example, compounds which serve to support the homogenization of the starting materials. Mention may be made, for example, of emulsifiers, such as the sodium salts of castor oil sulfates or of fatty acids, and salts of fatty acids with amines, e.g. diethylamine oleate, diethanolamine stearate, diethanolamine ricinoleate, salts of sulfonic acids, e.g. Oligomeric acrylates with polyoxyalkylene and fluoroalkane radicals as side groups are also suitable for improving the emulsifying effect.

The surface-active substances are usually used in amounts of 0.01 to 5 parts by weight, based on 100 parts by weight of the polyol.

Examples of suitable further release agents are: reaction products of fatty acid esters with polyisocyanates, salts of amino-containing polysiloxanes and fatty acids, salts of saturated or unsaturated (cyclo)aliphatic carboxylic acids having at least 8 carbon atoms and tertiary amines and, in particular, internal release agents such as carboxylic acid esters and/or or amides, produced by esterification or amidation of a mixture of montanic acid and at least one aliphatic carboxylic acid having at least 10 carbon atoms with at least difunctional alkanolamines, polyols and/or polyamines Molecular weights of 60 to 400 g/mol, as disclosed for example in EP 153639, mixtures of organic amines, metal salts of stearic acid and organic mono- and/or dicarboxylic acids or their anhydrides, as disclosed for example in DE-A-3 607 447, or mixtures from an imino compound, the metal salt of a carboxylic acid and optionally a carboxylic acid as disclosed for example in US 4,764,537. Reaction mixtures according to the invention preferably contain no further release agents.

Fillers, in particular fillers with a reinforcing effect, are to be understood as meaning the customary organic and inorganic fillers, reinforcing agents, weighting agents, coating agents, etc. known per se. Specific examples include: inorganic fillers such as silicate minerals, for example phyllosilicates such as antigorite, bentonite, serpentine, hornblende, amphibole, chrisotile and talc, metal oxides such as kaolin, aluminum oxide, titanium oxide, zinc oxide and iron oxide, metal salts such as chalk and barite, and inorganic pigments such as cadmium sulfide, zinc sulfide, and glass, etc. Preferably used are china clay, aluminum silicate, and co-precipitates of barium sulfate and aluminum silicate and glass fibers. Suitable organic fillers are, for example: carbon black, melamine, rosin, cyclopentadienyl resins and graft polymers and cellulose fibers, polyamide, polyacrylonitrile, polyurethane, polyester fibers based on aromatic and/or aliphatic dicarboxylic acid esters and in particular carbon fibers.

The inorganic and organic fillers can be used individually or as mixtures and are advantageously added to the reaction mixture in amounts of 0.5 to 50% by weight, preferably 1 to 40% by weight, based on the weight of the polyurethane elastomer composition (v).

The polyurethane elastomer preparation (v) of the bearing according to the invention also has excellent mechanical properties, in particular the values for tensile strength, elongation at break, tear propagation resistance and abrasion are very good and, for example, also improved compared to the conventional method with direct addition of the molten chain extender to the prepolymer. The hardness of the polyurethane elastomer preparation (v) can be adjusted via the formulation in the range from 50 to 90 Shore A, preferably in the range from 60 to 80 Shore A, more preferably in the range from 60 to 75 Shore A, particularly preferably in the range from 62 to 72 Shore A can be set. Isocyanate index:

In a preferred embodiment, the isocyanate index during production of the polyurethane preparation is from 85 to 130, preferably from 90 to 120, more preferably from 95 to 110, more preferably from 100 to 103, more preferably from 101 to 103, and the isocyanate index is very particularly preferably 102. The isocyanate index is calculated stoichiometrically from the ratio of reactive isocyanate groups of the isocyanate used to the group of the polyol used which is reactive with the isocyanate group multiplied by 100.

Another subject of this invention is the use of the polyurethane elastomer preparation (v) described here for vibration damping or vibration decoupling, in particular for the frequency range between 30 Hz and 5000 Hz.

Microcellular polyurethane

The production of the microcellular polyurethane used in particular embodiments in addition to the polyurethane elastomer preparation is known in principle and is described, for example, in WO9710278 or WO2018/087387.

The cellular polyisocyanate polyaddition products particularly preferably have at least one of the following material properties: a density according to DIN EN ISO 845 between 200 and 1100 kg/m ³ , preferably between 270 and 900 kg/m 3 , a tensile strength according to DIN EN ISO 1798 of >2, 0 N/mm 2 , preferably > 4 N/mm ² , particularly preferably between 4 and 8 N/mm ² , an elongation at break according to DIN EN ISO 1798 of > 200%, preferably > 230%, particularly preferably between 300% and 700% and/or a tear propagation resistance according to DIN ISO 34-1 B (b) > 6 N/mm, of > 8 N/mm, particularly preferably > 10 N/mm. In more preferred embodiments, the cellular polyisocyanate polyaddition product has two, more preferably three, of these material properties; particularly preferred embodiments have all four of the material properties mentioned.

The elastomers based on cellular polyisocyanate polyadducts are usually produced in a form in which the reactive starting components are reacted with one another. Here, generally customary forms come into question as forms, for example metal forms, which, due to their form, ensure the three-dimensional form of the spring element according to the invention. In preferred embodiments, the microcellular polyurethane is injected directly into the spaces of the bearing intended for it.

The production of the microcellular polyurethane can be carried out according to generally known methods, for example by using the following starting materials in a one- or two-stage process: (a) isocyanate,

(b) isocyanate-reactive compounds,

(c) water, optionally in the presence of

(d) catalyst,

(e) propellant,

(f) auxiliary and/or additive.

The production of the microcellular polyurethanes is advantageously carried out at an NCO/OH ratio of 0.85 to 1.20, with the heated starting components being mixed and placed in the mold in an amount corresponding to the desired molding density.

The amount of reaction mixture introduced into the mold is usually such that the moldings obtained have the density already mentioned.

The starting components are preferably introduced into the mold at a temperature of from 15 to 120.degree. C., preferably from 30 to 110.degree. The degrees of compression for producing the shaped bodies are between 1.1 and 8, preferably between 2 and 6.

The cellular polyisocyanate polyaddition products are expediently produced by the one-shot process using low-pressure technology or, in particular, reaction injection molding (RIM) in open or preferably closed molds. The reaction is carried out in particular with compression in a closed mold. The reaction injection molding technique is described, for example, by H. Piechota and H. Röhr in "Integral foams", Carl Hanser-Verlag, Munich, Vienna 1975; DJ Prepelka and J.L. Wharton in Journal of Cellular Plastics, March/April 1975, pages 87-98 and U. Knipp in Journal of Cellular Plastics, March/April 1973, pages 76-84.

Suitable isocyanates are all isocyanates which have also been described above for the polyurethane elastomer preparation (v). The microcellular polyurethane is preferably produced with isocyanate-terminated prepolymers, preferably with isolates based on 2,2'-, 2,4'- and/or 4,4'-diphenylmethane diisocyanate (MDI) or 1,5-naphthylene diisocyanate (NDI) prepared, preferably on the basis of 1, 5-naphthylene diisocyanate (NDI).

The isocyanate-reactive compound (b) has a statistical average of at least 1.8 and at most 3.0 Zerewitinoff-active hydrogen atoms; this number is also referred to as the functionality of the isocyanate-reactive compound (b) and indicates the theoretical down-calculated from a quantity of substance to one molecule Amount of isocyanate-reactive groups on the molecule. The functionality is preferably between 1.8 and 2.6, more preferably between 1.9 and 2.2 and in particular 2. Compounds which are reactive toward isocyanates are preferably polyester diols and polyether diols. .

Polyetherdiols based on ethylene oxide, propylene oxide and/or butylene oxide are preferred. A particularly preferred polyether is polytetrahydrofuran (PTHF).

A particularly preferred polyester is polycaprolactone. Also preferred are the Polyesteroie from the following group: copolyesters based on adipic acid, succinic acid, pentanedioic acid, sebacic acid or mixtures thereof and mixtures of 1,2-ethanediol and 1,4-butanediol, copolyesters based on adipic acid, succinic acid, pentanedioic acid, sebacic acid or their Mixtures and mixtures of 1,4-butanediol and 1,6-hexanediol, polyesters based on adipic acid and 3-methyl-1,5-pentanediol and/or polytetramethylene glycol (polytetrahydrofuran, PTHF). Copolyesters based on adipic acid and mixtures of 1,2-ethanediol and 1,4-butanediol or polyesters based on adipic acid, succinic acid, pentanedioic acid, sebacic acid, or mixtures thereof and polytetramethylene glycol (PTHF) are particularly preferred.

Another important component of microcellular polyurethane is water. Water acts as a blowing agent. It can be used alone or with other blowing agents. Water is preferably used as the sole blowing agent.

Further catalysts, auxiliaries and/or additives can be added to the microcellular polyurethane, as have already been mentioned by way of example for the polyurethane elastomer preparation (v).

vibration decoupling

In a preferred embodiment 23, which contains all the features of one of the previous embodiments or one of their preferred embodiments, the polyurethane preparation (v) dampens forces in the frequency range from 1 Hz to 30 Hz, preferably in the frequency range from 8 Hz to 15 Hz

In a preferred embodiment 24, which incorporates all features of any of the previous embodiments or one of their preferred embodiments, the polyurethane elastomer preparation (v) polyurethane elastomer exhibits a maximum of vibration isolation in the range between 30 Hz to 5000 Hz. The dynamic hardening is used to evaluate the vibration decoupling. The dynamic hardening is the quotient of the bearing stiffness for a dynamic and a quasi-static load on the bearing, i.e. c _d / c _s

The bearing stiffness under a dynamic load Cd is calculated from the gradient of the force-displacement curve with a sinusoidal excitation under a defined preload. the Bearing stiffness under quasi-static load Cs is calculated from the slope of the force-displacement curve at the same preload point. See also Example 2 and Figure 5

The bearing stiffness cd is calculated from the gradient of the force-displacement curve with a sinusoidal excitation, preferably with an excitation amplitude of 0.1 mm. The bearing damping D is represented as a loss angle, which indicates the phase shift of the output signal (force amplitude) compared to the input signal (displacement amplitude) with a sinusoidal excitation with an excitation amplitude of 0.1 mm. The frequency f represents the number of sinusoidal excitations per second.

To calculate the dynamic hardening, the quotient of the dynamic stiffness Cd at a frequency of 100 Hz and the static stiffness c _s is calculated for the respective load directions. The respective values for Cs and Cd. These can be taken from FIG. 5 or FIG. 6 by way of example.

Low dynamic hardening is preferably understood to mean dynamic hardening of less than 1.6, measured at an excitation frequency of 100 Hz and an excitation amplitude of 0.1 mm. Dynamic hardening under these conditions is more preferably less than 1.5, more preferably less than 1.4 and particularly preferably less than 1.3.

Method of manufacture

Another object of this invention and an embodiment 25 is a method for producing a bearing according to one of the above embodiments or their preferred embodiments, wherein the cavity (iii) of the bushing is closed so that the cavity (iii), at least partially with the Casting elastomer preparation can be poured out. The preparation of all components of the polyurethane elastomer preparation (v) is referred to as cast elastomer preparation as long as the structural components have not yet reacted, ie the preparation is still flowable. The casting elastomer preparation contains the structural components, if necessary additionally with a catalyst, auxiliary substance, additive, carbodiimide or mixtures thereof. The cast elastomer composition is introduced into the cavity (iii) of the bush (ii) in which the fastener is in its final position relative to the bush or into which the fastener is placed in its final position relative to the bush before the cast elastomer composition cures to form the polyurethane elastomer composition. In an embodiment 26, which includes all features of the previous methods or one of the preferred embodiments, molds are introduced into the cavity between bushing (ii) and fastener (iv), which can be removed after curing of the cast elastomer composition to the polyurethane elastomer composition and so to Lead gaps in the polyurethane elastomer preparation.

To produce the polyurethane casting elastomer according to the invention, the components of the polyurethane casting elastomer system, also referred to as casting elastomer preparation, are mixed preferably at temperatures of 30 to 95° C., particularly preferably 40 to 95° C., more preferably 55 to 95° C. and in particular at 85 to 95° C. This mixture is then cured, preferably in a mold, to give the polyurethane casting elastomer (v). The mold temperatures are usually from 0 to 130.degree. C., preferably from 60 to 120.degree. C. and particularly preferably from 80 to 110.degree. The components are usually mixed in low-pressure machines or high-pressure machines, preferably in high-pressure machines. The high-pressure machine is advantageous because the Shore hardness can be adjusted in-line by mixing at the mixing head. The high-pressure process saves time-consuming cleaning of the mixing head.

In a preferred embodiment, the isocyanate index in the production of the polyurethane elastomer preparation (v) is 85 to 130, preferably 90 to 120, more preferably 95 to 110, more preferably 100 to 103, more preferably 101 to 103, and the isocyanate index is very particularly preferably 102. The isocyanate index is calculated stoichiometrically from the ratio of reactive isocyanate groups of the isocyanate used to the isocyanate-reactive groups of the polyol used, multiplied by 100.

The finished polyurethane casting elastomers are preferably post-cured after demolding at elevated temperatures to further improve the mechanical properties. The polyurethane casting elastomer (v) is preferably cured at 50° C. to 120° C., preferably at 60° C. to 110° C. and in particular at 80° 100ºC to 100ºC. This tempering preferably takes place over a period of 10 to 24 hours.

use of the warehouse

The bearing is used in particular for the vibration decoupling of electric motors, since the preferred embodiments in particular decouple the vibrations generated by an electric motor well. The bearing is preferably used in vehicles that contain an electric motor. This electric motor is preferably used to drive the vehicle. In a preferred embodiment, the bearing is mounted on a frame. The electric motor is connected to the frame via one or more bearings in preferred embodiments. In a preferred embodiment, the frame itself is connected to the vehicle body via four bearings.

Examples:

Example 1 - Manufacture of a bearing

A bearing was made from an outer bushing (ii) with a collar, an inner fastening element connected via a polyurethane elastomer preparation with two continuous recesses (vi) according to Figure 7.

The outer bushing is injection molded from a 30% glass fiber reinforced [6, 6] polyamide. The outer bush has an outside diameter of 74 mm, an inside diameter of 68 mm and a length of 62 mm.

The outer bush (ii) was degreased with perchlorethylene on the inner surface in contact with the polyurethane elastomer preparation and roughened with steel grit using a trough belt blaster to an average peak-to-valley height of 25-50 μm.

A polyurethane adhesion promoter (CILBOND® 45SF) was then sprayed on with a layer thickness of approx. 15 - 25 μm. This was dried at a temperature of 80° C. for 10 minutes.

An aluminum alloy EN AW-6082 (AI SilMgMn) with a cylindrical through hole was used for the fastener. The fastener has an outer diameter of 48mm, an inner diameter of 22mm and a length of 65mm.

The fastening element was first degreased on the outer contour with perchlorethylene (Per) and roughened by trough belt blasting with steel grit to an average peak-to-valley height of 25 - 50 μm.

Then the adhesion promoter (CILBOND® 45SF) was applied by spraying up to a layer thickness of 15 - 25 μm. This was dried at a temperature of 80° C. for 10 minutes.

To produce the casting elastomer, the A component (polyol component) and B component (isocyanate component) were provided in the proportions shown in Table 1 below.

The A component was mixed well under vacuum for two minutes and stored between 40 °C and 50 °C for 30 minutes.

To produce the B component, the isocyanate mixture according to Table 1 was placed under a nitrogen atmosphere at 60° C. and then the polytetrahydrofuran (pTHF)-based polyol mixture was metered in in small amounts. After complete addition, the mixture was heated to 80°C to 90°C and maintained at this temperature for two hours. The B component was cooled and stored between 40°C and 50°C. 23

Directly before the mixing of the A component and the B component, the A component was again homogenized with a mixer for two minutes under vacuum. The mixing ratio of the A and B components was set according to the index given in the table. The index is the ratio of isocyanate to groups reactive with the isocyanate multiplied by 100).

The A component was combined with the B component, mixed for 30 seconds under vacuum at 1750 rpm and poured into molds preheated between 90°C and 100°C. After 60 minutes, the specimens were demoulded and between for 48 hours. Tempered at 85°C and 95°C.

Table 1 - Cast elastomer formulations 24

* 50% dispersion of zeolite A particles in castor oil, the zeolite A particles having a pore size of 0.3 nm, an average particle size of 5 μm and a sieve residue (0.042 mm sieve) of approx. 0.1% or have less.

** For Polycat SA 1/10 from Air Products Chemicals Europe B.V. is a heat-activatable diazabicycloundecene-bicycloundecene (DBU)).

To shape the polyurethane elastomer formulation, the mold was heated to a temperature of 90°C. The outer sleeve (ii) and fastener were also heated to 90°C. The high-pressure mixing head was guided with the outlet nozzle to a sprue bushing in the casting tool.

After a dwell time of 10 minutes, the casting tools were removed.

Example 2 - measurement of the bearing

To demonstrate the suitability of the composition and contouring of the polyurethane elastomer preparation for the specific application, the bearings produced according to Example 1 were tested both quasi-statically and dynamically. That's what it became Bearing first pressed into a bearing mount (viii), which corresponds to the geometry of the bearing seat in the vehicle.

Bearing tests were performed using a servo-hydraulic testing machine, an Instron Hydropuls® MHF. The bearing mount (viii) with the pressed-in bearing (i) was connected to the force transducer of the testing machine (x) via the bracket (ix). The fastening element (iv) was connected directly to the movable piston of the testing machine for the axial test direction or via the test device (xi) for the radial test direction and loaded in the various spatial directions.

Example 2a - quasi-static test

The bearing was first preloaded in two setting cycles with a test speed of 30 mm/min, and then in the measuring cycle with a test speed of 10 mm/min initially loaded up to a force F = 8kN with radial load or F = 3kN with axial load and then relieved up to a force F = -8kN with radial load or F = -3kN with axial load. This is also known as "quasi-static loading". The deflection of the bushing as a result of the load was recorded via the applied force in different directions of the bearing using the displacement transducer of the testing machine and evaluated in the form of a force-displacement characteristic. The characteristic curves were corrected for the structural rigidity of the testing machine and the testing device.

Results of the measurement of the bearing with formulation 6 are shown in FIGS. 5a) to 5c). Recipe 7 delivers comparably good results.

Example 2b - Dynamic Check

For the dynamic test, the bush was fixed via the bearing mount and dynamically loaded in the various spatial directions via the fastening element. The bearing was loaded with a sinusoidal path signal with an amplitude of 0.05 mm at different excitation frequencies in the range from 1 Hz to 200 Hz. The force resulting from the deflection of the bushing was recorded with the force transducer of the testing machine and evaluated in the form of a force-displacement characteristic. The dynamic stiffness and the loss angle were determined from these characteristic curves as a measure of the damping and their progression over the frequency was shown. The values for the bearing from Example 1 are shown in FIG.

To calculate the dynamic hardening, the quotient of the dynamic stiffness c _d at a frequency of 100 Hz and the static stiffness c _s was calculated for the respective load directions. The respective values for c _s and Cd can be found in FIG. 5 and FIG 6 can be removed. The bearings have a dynamic hardening of 1.21 in the x loading direction, 1.18 in the y loading direction and 1.22 in the z loading direction. The dynamic hardening is therefore clearly in the particularly preferred range of less than 1.3 in all load directions.

References:

(i) Warehouse

(ii) outer bushing

(iii) cavity

(iv) Fastener

(v) compact polyurethane elastomer formulation

(vi) continuous recess

(vii) partial recess

(viii) Storage

(ix) Bracket

(x) testing machine

(xi) Testing Device

Hints:

Mechanical properties, if definable, can be included.

Claims

28 claims:

1 . Vibration damping mount (i) comprising a bushing (ii) surrounding a cavity (iii) and a fastener (iv) located in said cavity (iii), in which cavity a compact polyurethane elastomer composition (v) is located that connects the outer sleeve (ii) to the fastener (iv), characterized in that

Polyurethane elastomer in the polyurethane elastomer preparation (v) the reaction product is made up of the following structural components a. a diisocyanate b. a polyester diol, a polyether diol, or a mixture thereof c. a chain extender and the preparation optionally also contains at least one of the following components d. catalyst e. excipient f. additive

2. Bearing according to claim 1, characterized in that between the bushing (ii) and the polyurethane elastomer preparation (v) or between the polyurethane elastomer preparation (v) and the fastening element (iv) or between the polyurethane elastomer preparation (v), the bushing (ii) and the fastener (iv) is an adhesion promoter.

3. Bearing according to one of the preceding claims, characterized in that the bushing is axisymmetric.

4. Bearing according to one of the preceding claims, characterized in that the fastening element lies on the axis of the axisymmetric bushing.

5. Bearing according to any one of the preceding claims, characterized in that the polyurethane elastomer composition is not evenly distributed in the cavity of the bush.

6. Bearing according to one of the preceding claims, characterized in that the polyurethane elastomer preparation contains a recess. Bearing according to the preceding claim, characterized in that the recess contains microcellular polyurethane. Bearing according to any one of the preceding claims, characterized in that the polyester diol and the polyether diol are linear and preferably consist of monomers containing between 4 and 20 carbon atoms, more preferably 4 to 10 carbon atoms, more preferably 4 to 7 carbon atoms. Bearing according to one of the preceding claims, characterized in that the polyether diol is polytetrahydrofuran (PTHF) and the polyester diol is polycaprolactone. Bearing according to one of the preceding claims, characterized in that the structural components are diisocyanate, polytetrahydrofuran and chain extenders. Bearing according to one of the preceding claims, characterized in that the polyurethane elastomer also contains a carbodiimide, preferably based on a diisocyanate. Bearing according to one of the preceding claims, characterized in that the polyurethane elastomer has a dynamic hardening of less than 1.3. Bearing according to one of the preceding claims, characterized in that the polyurethane elastomer has a hardness of 62 to 72 Shore A. A method of manufacturing a bearing according to any one of claims 1 to 13, characterized in that a. that the cavity (ii) of the bushing (ii) is closed in such a way that the cavity (iii) can be at least partially filled with the polyurethane elastomer (v), the starting components together, optionally additionally with a catalyst, auxiliary material, additive, carbodiimide, or mixtures thereof, are mixed to form a cast elastomer, b. and introducing said cast elastomer into the cavity of the bushing in which the fastener is in its final position relative to the bushing or into which the fastener is placed in its final position relative to the bushing before the cast elastomer cures to form the polyurethane elastomer.