Acoustic attenuation material having improved low temperature adhesion - Patents.com

Abstract

The present invention is directed to an acoustic damping material comprising at least one polybutadiene PB, at least one rubber LR that is liquid at 25°C, at least one butyl rubber BR, at least one natural or synthetic polyisoprene PI, at least one hydrocarbon resin HR, and at least one solid particle filler FM. The acoustic damping material is suitable for use in damping undesirable vibrations and noise in mechanical structures and components of products. The present invention is also directed to the use of the acoustic damping material for damping vibrations and noise in transport vehicles and white goods; a vibration and noise damping element comprising an adhesive layer composed of the acoustic damping material; a method for applying the vibration and noise damping element to a noise-generating surface of a substrate; and a vibration-damped system comprising a substrate and a vibration and noise damping element bonded to the noise-generating surface of the substrate.

Description

[Technical field]

[0001] The present invention relates to compositions used to dampen vibrations and noise in mechanical structures of products, particularly compositions suitable for damping vibrations in components and structures contained within articles of the automotive industry, household appliances, and general industry. [Background technology]

[0002] Acoustic damping materials are widely used in the automotive, appliance, and general industries to reduce unwanted vibration, structure borne noise, and air borne noise. For example, in an automobile, it is desirable to prevent vibrations generated by motors, pumps, gears, and other dynamic force sources from transferring through the vehicle body into the passenger compartment. Structure borne noise occurs when vibrations from dynamic force sources transfer through a support structure, typically a frame or other hollow structure, to noise-generating surfaces, such as metal or plastic panels, which convert the mechanical vibrations into sound waves. Structure borne noise and vibration can generally be effectively reduced by applying vibration damping materials directly to the surfaces of structures and components where the vibrational disturbances are generated, such as vehicle panels, floor surfaces, and the shells of machines, washers, and dryers.

[0003] Acoustic damping materials used to dampen vibrations in panels and plates are generally provided in the form of preformed single and multi-layer damping elements or as liquid compositions that are applied directly to the surface of a substrate. Damping materials designed to dampen vibrations and noise within hollow structures, e.g., cavities, are usually provided in the form of a cavity filler insert that includes a foamable composition and one or more attachment elements that enable the cavity filler insert to be held in a desired position within the hollow structure.

[0004] Preformed single-layer and multi-layer damping elements include a damping layer that is in direct contact with the surface of the substrate to be damped against vibrational disturbances. The damping layer is capable of dissipating the kinetic energy of the vibrating surface into thermal energy through the expansion and contraction of the material of the damping layer. Widely used materials for the damping layer include bituminous and rubber-based compositions that contain relatively high contents of particle fillers and various amounts of additives, in particular plasticizers, rheology modifiers, and desiccants. Preformed single-layer and multi-layer damping elements often include a layer of an adhesive composition, such as a pressure-sensitive adhesive (PSA) or a hot melt adhesive, allowing the damping layer to be bonded to the surface of the substrate, such as a panel or floor of an automobile. Liquid-applied damping systems are typically heat-drying, gelling, or reactive compositions that are applied in liquid form to the surface of the substrate, for example by spraying.

[0005] Acoustic damping materials used to dampen vibrations of panels and plates can also be provided in the form of constrained layer damping elements, which include a damping layer and a stiff outer layer that sandwiches and "constrains" the damping layer between the stiff outer layer and the surface of the substrate to be damped. The stiffness of the outer layer is typically ten times higher than the stiffness of the layer of damping material. Commonly used materials for the outer top layer include, for example, aluminum and fiberglass cloth. Constrained layer dampers are typically more effective at damping unwanted vibrations than single layer damping elements, but they are more expensive to manufacture.

[0006] Cavity filler inserts are used to attenuate air-borne noise inside the cavity of a hollow structural component and to prevent vibration transmission through the cavity wall. Cavity filler inserts typically consist of a damping material and at least one mounting member that allows the cavity filler insert to be held in a desired position inside the hollow structure. The damping material of the cavity filler insert is typically formulated as a foamable composition that, when activated, for example at elevated temperature, expands to form a seal with the interior surface of the cavity wall. Foamable damping materials suitable for attenuating air-borne noise inside a cavity are commonly referred to as "acoustic baffles".

[0007] Bitumen-based compositions have been widely used as acoustic damping materials in the automotive and household appliance industries because they combine low-cost raw materials with high vibration damping performance, as well as reliable and easily controllable physical properties. In the household appliance market, bitumen-based damping systems currently have almost 100% market share. Highly filled bitumen compositions have been used in particular to provide sound-proofing and sound-reducing coatings, which are applied to metal and plastic components in the assembly process of automobiles and household appliances. In a conventional procedure, a mixture of bitumen and filler is first extruded and / or calendared to form a film, and then a suitable molded part suitable for use as a damping element is prepared by punching or die cutting. The damping element is then bonded to the metal or plastic sheet to be damped. The molded part can also be further processed by heating to conform to the shape of the metal or plastic sheet.

[0008] US Patent Publication No. 2017267842 discloses heat curable compositions including solid rubber, olefinic double bond-containing polymer, hydrocarbon, liquid polydienes, and a vulcanization system, and their use as noise suppression materials in vehicles. Also disclosed is a process for applying the composition, which comprises injecting it by a pump at a temperature ranging from 15 to 60° C. to the point of application and depositing it on a substrate in liquid or paste form.

[0009] US6361643 discloses one-component, heat-curable reactive compositions based on liquid rubber containing reactive olefinic double bonds and optionally solid rubber and sulfur-based vulcanization systems, which in their vulcanized form have high acoustic loss factor maxima over a wide service temperature range of approximately +10°C to +40°C. These compositions optionally contain particulate thermoplastic polymers as additional components. These compositions are suitable for use as adhesives, sealing compounds or coating compositions for noise attenuation.

[0010] Among the main application areas of sound damping elements are automotive interiors and washing machines for home appliances. In these applications, especially in the case of automobiles, the sound damping materials are exposed to low temperature exposure. In the automotive industry, the quality and performance of components used in automobiles at low temperatures of approximately -20 to -40°C are controlled by the automobile manufacturers. For example, a drop ball test at -30°C is used to evaluate the adhesion of sound damping elements in cold weather. Traditional materials for use in automotive and white good applications have deficiencies in performance at low temperatures, especially at -30°C.

[0011] Therefore, there is a need for a new type of acoustic damping material that exhibits good performance in the ball drop test at low temperatures, particularly at -30°C, preferably has good adhesion to the substrate to which it is applied, and provides equivalent or improved vibration and noise damping performance compared to state of the art rubber-based damping materials. Summary of the Invention [Problem to be solved by the invention]

[0012] It is an object of the present invention to provide a material for use in damping unwanted vibrations and noise in mechanical structures and product components, which material further has improved performance in low temperature, particularly at -30°C, ball drop tests compared to state of the art rubber-based sound damping materials.

[0013] The subject of the invention is an acoustic damping material as defined in claim 1.

[0014] Surprisingly, it has been found that the acoustic damping material according to the invention exhibits comparable or even improved vibration and noise damping performance compared to commercially available rubber-based acoustic damping materials. In particular, it has been found that the acoustic damping material of the invention exhibits high vibration damping performance (defined by loss factor at temperatures in the range of approximately 10-20° C.), thereby making it particularly suitable for use in the vibration and noise damping of automotive structures and components.

[0015] Further subject matter of the invention is set out in the other independent claims. Preferred embodiments of the invention are set out in the dependent claims. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a cross-sectional view showing a vibration and noise damping element (1) including a damping layer (2) having a first surface (3) and a second surface (3'), and an adhesive layer (4) covering the first surface (3) of the damping layer (2). [Diagram 2]FIG. 1 is a cross-sectional view showing a vibration and noise damping element (1) including a damping layer (2) having a first surface (3) and a second surface (3'), an adhesive layer (4) covering the first surface (3) of the damping layer (2), and a constraining layer (5) covering the second surface (3') of the damping layer (2). [Diagram 3] FIG. 1 is a cross-sectional view showing a vibration-damped system including a substrate (6) having a noise-generating surface (7) and a vibration and noise-damping element (1) including a damping layer (2) and an adhesive layer (4), where a first surface (3) of the damping layer (2) is adhesively bonded to the noise-generating surface (7) via the adhesive layer (4). [Figure 4] FIG. 1 is a cross-sectional view showing a vibration-damped system including a substrate (6) having a noise-generating surface (7) and a vibration and noise-damping element (1) including a damping layer (2), an adhesive layer (4), and a constraining layer (5), where a first surface (3) of the damping layer (2) is adhesively bonded to the noise-generating surface (7) via the adhesive layer (4), and where the damping layer (2) is sandwiched between the adhesive layer (4) and the constraining layer (5). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The subject of the present invention is an acoustic damping material comprising: a) at least one polybutadiene PB containing monomer units derived from 1,3-butadiene in an amount of 0.75% by weight or more, based on the total weight of the acoustic damping material; [ka] wherein the proportion of monomer units of formula (I) among all monomer units derived from 1,3-butadiene present in the polybutadiene is from 25 to 75 mole percent, the proportion of units of formula (II) among all monomer units derived from 1,3-butadiene present in the polybutadiene is from 0 to 10 mole percent, and the proportion of monomer units of formula (III) among all monomer units derived from 1,3-butadiene present in the polybutadiene is from 25 to 75 mole percent, wherein the total of the monomer units (I), (II), and (III) is 100 mole percent, and the polybutadiene preferably has an average molecular weight of from 1000 to 4000 g / mol; b) at least one rubber LR that is liquid at 25° C. selected from the group consisting of polybutene that is liquid at 25° C. and polyisobutylene that is liquid at 25° C., preferably polyisobutylene that is liquid at 25° C., in an amount of 10% by weight or more based on the total weight of the sound-damping material; c) at least 3% by weight of at least one butyl rubber BR, based on the total weight of the sound-damping material; d) 3% by weight or more of at least one natural or synthetic polyisoprene PI, preferably natural polyisoprene, most preferably natural rubber, based on the total weight of the sound-damping material; e) 4 to 15 weight percent, based on the total weight of the acoustic damping material, of at least one hydrocarbon resin HR; f) at least one solid particle filler FM.

[0018] Substance names beginning with "poly" technically refer to substances that contain more than one of the functional groups in their names per molecule. For example, a polyol refers to a compound that has at least two hydroxyl groups. A polyether refers to a compound that has at least two ether groups.

[0019] The term "polymer" refers to a chemically homogeneous group of macromolecules produced by polymerization reactions (polymerization, polyaddition, polycondensation), where the macromolecules differ in degree of polymerization, molecular weight, and chain length. The term also includes derivatives of said generic macromolecules resulting from polymerization reactions, i.e., compounds obtained, for example, by addition or substitution reactions of functional groups in a predefined macromolecule, and which may be chemically homogeneous or chemically heterogeneous.

[0020] The term "molecular weight" refers to the molar mass (g / mol) of a molecule or a part of a molecule (also called a "moiety"). The term "average molecular weight" refers to the number average molecular weight (M n The molecular weight can be determined by conventional methods, preferably gel permeation chromatography (GPC), using polystyrene as the standard, styrene-divinylbenzene gels with porosities of 100 angstroms, 1000 angstroms, and 10000 angstroms, depending on the molecule, as columns, and tetrahydrofuran as solvent at a temperature of 35° C. or 1,2,4-trichlorobenzene as solvent at 160° C.

[0021] "Glass transition temperature" (T g The term glass transition temperature (T) refers to the temperature above which a polymer component becomes soft and pliable and below which it becomes hard and glassy. g ) is preferably measured by dynamic mechanical analysis (DMA) as the peak of the loss modulus (G") curve measured at a frequency of 1 Hz and an applied strain of 0.1%.

[0022] The term "softening point" refers to the temperature at which a compound softens to a rubber-like state or at which crystalline parts of a compound melt. The softening point can be determined by the Ring and Ball measurement performed according to the DIN EN 1238 standard.

[0023] The term "room temperature" refers to a temperature of 23°C.

[0024] The acoustic damping material of the present invention is particularly suitable for use in damping unwanted vibrations and noise in mechanical structural elements of products, such as automobiles or household appliances or general industrial products. In these applications, the acoustic damping material, typically provided in the form of a shaped article, such as a layer or pad, is applied directly to the surface of the mechanical structure or component that faces the vibration disturbance. The acoustic damping material can be formed into a suitable shaped article by using conventional extrusion and / or calendaring or hot pressing methods. The types and amounts of components a) to f) of the acoustic damping material can be optimized to maximize the efficiency of the material in dissipating the kinetic energy of the vibrating surface into thermal energy through the expansion and contraction of the damping material in the temperature range relevant to the application.

[0025] Preferably, the acoustic attenuation material of the present invention is essentially free of bitumen. The expression "essentially free" is understood to mean that the acoustic attenuation contains only trace amounts of bitumen, for example less than 0.5% by weight, preferably less than 0.25% by weight, more preferably less than 0.1% by weight, and even more preferably less than 0.01% by weight, based on the total weight of the acoustic attenuation material. The term "bitumen" in this disclosure refers to heavy hydrocarbon blends having a solid consistency at room temperature. They are usually obtained as vacuum distillation residues from the distillation (topping or vacuum distillation) and / or secondary processing processes, such as pyrolysis and visbreaking, of suitable crude oils and refining processes. Furthermore, the term "bitumen" also refers to natural and synthetic bitumen, as well as bituminous materials obtained from the extraction of tar and bituminous sand.

[0026] Furthermore, it will be preferred that the acoustically attenuating material is substantially free of crosslinking / curing agents such as free radical crosslinkers, e.g. peroxides. The term "substantially free" is intended to mean that if any crosslinking agent is found in the acoustically attenuating material, the amount is so negligible that the crosslinking agent has no effect. In other words, the amount of crosslinking agent found in the acoustically attenuating material is incapable of initiating curing of the polymeric components or is capable of initiating only substantially negligible crosslinking. In one or more embodiments, the acoustically attenuating material contains less than 0.15 wt. %, preferably less than 0.1 wt. %, more preferably less than 0.01 wt. %, and even more preferably 0 wt. % crosslinking / curing agent, based on the total weight of the acoustically attenuating material.

[0027] The acoustic dampening material includes at least one polybutadiene PB containing monomer units derived from 1,3-butadiene in an amount of 0.75% by weight or more, based on the total weight of the acoustic dampening material; [ka] wherein the ratio of the units of formula (I) in the total monomer units derived from 1,3-butadiene present in the polybutadiene is 25 to 75 mol percent, preferably 50 to 65 mol percent, preferably 59 to 62 mol percent, the ratio of the units of formula (II) in the total monomer units derived from 1,3-butadiene present in the polybutadiene is 0 to 10 mol percent, preferably 1 to 8 mol percent, preferably 2 to 6 mol percent, and It is preferred that the proportion of units of formula (III) present among all monomeric units derived from 1,3-butadiene is between 25 and 75 mole percent, preferably between 25 and 40 mole percent, preferably between 35 and 39 mole percent, provided that the total of all monomeric units (I), (II) and (III) totals 100 mole percent, and that the polybutadiene has an average molecular weight between 1000 and 4000 g / mol, preferably between 1200 and 3500 g / mol, preferably between 1500 and 3000 g / mol.

[0028] In the context of the present invention, the term "polybutadiene" is understood to mean a reaction product obtainable by polymerizing monomer units each having at least two conjugated double bonds, of which, for increased suitability, at least 80%, preferably at least 85%, preferably at least 90%, preferably at least 95%, preferably at least 98%, preferably at least 99%, most preferably at least 99.9%, preferably all, are 1,3-butadiene. Possible further compounds (impurities) may be, for example, alkanes or alkenes having 3 to 5 carbon atoms, in particular propene, 1-butene or 1,2-butadiene.

[0029] Surprisingly, it was found that amounts less than 0.75 wt.% resulted in poor low temperature ball drop test performance, which can be seen by comparing Refs. 1-3 with E1-E5.

[0030] Preferably, the amount of at least one polybutadiene PB is 1-15% by weight, preferably 1.2-10% by weight, preferably 1.3-8% by weight, preferably 1.5-7% by weight, preferably 1.5-5% by weight, most preferably 1.5-3% by weight, based on the total weight of the sound damping material. This is advantageous in terms of good low temperature ball drop test performance, high adhesive strength, and cohesive failure pattern. This can be seen by comparing Ref.3 with E1-E5.

[0031] In the monomer units represented by formulae (I), (II), and (III), the brackets in the formulae selected herein indicate the monomer units (I), (II), and (III) present in the polybutadiene that are derived from 1,3-butadiene, and the bond marked by each bracket does not end, for example, in a methyl group, but instead the relevant monomer unit is bonded to another monomer unit through this bond. In this case, the monomer units (I), (II), and (III) may be arranged in any desired sequence in the polymer. A random arrangement is preferred.

[0032] The proportion of monomer units in the polybutadiene PB that do not conform to any of formulas (I), (II) or (III) is preferably less than 20 mol percent, preferably less than 5 mol percent, particularly preferably less than 1 mol percent, and especially preferably less than 0.1 mol percent, based on the totality of the monomer units. The proportion of monomer units in the polybutadiene PB that do not conform to any of formulas (I), (II) or (III) can be controlled in the production process by using 1,3-butadiene that contains impurities, in particular dienes that are not 1,3-butadiene, correspondingly, preferably less than 20 mol percent, preferably less than 5 mol percent, particularly preferably less than 1 mol percent, and especially preferably less than 0.1 mol percent.

[0033] The molar ratio of the monomer units of formulae (I), (II) and (III) is preferably determined by IR spectroscopy with polybutadiene as a standard. For this purpose, the sample (approximately 80-250 mg) is dissolved in 10 mL of carbon disulfide (CS2). In the case of a high vinyl content, a lower concentration is used, in the case of a high cis content, a higher concentration is used. The measurement is carried out in an IR cell with a path length of 0.5 mm, with NaCl windows. After solvent subtraction, the spectrum is obtained from 1100 to 600 cm. -1 Express the absorbance in the evaluation range of 1. If the absorbance is higher than 1, repeat the measurement at a lower concentration. Determine the absorbance above the baseline at the following wavenumbers: trans-1,4-polybutadiene: 968 cm -1 1,2-Polybutadiene: 911 cm -1 cis-1,4-polybutadiene: 730 cm -1 .

[0034] The molar ratio of these monomeric components is preferably determined according to the following formula: %comp(i) = Ext(i)*100% / (E(i)*c*d*) [In the formula, Ext(i) = absorbance above baseline E(i) = extinction coefficient (substance specific, determined by calibration) [E]=L / (g*cm) d = cell path length (unit: cm) c = concentration of the sample (unit: g / L) [is].

[0035] The polybutadiene PB preferably has a viscosity of 2000 to 8000 mPa·s, preferably 3000 to 7000 mPa·s, at 20° C. This viscosity (cone and plate viscosity) is preferably measured according to DIN 53018 using a Rheometer Physica MCR301 (manufactured by ANTON PAAR Germany GmbH).

[0036] It will be advantageous if the polybutadiene PB has a dispersity of 2.1 to 3.0. The dispersity is defined as the number average molar mass (Mn) divided by the weight average molar mass (Mw).

[0037] Particularly preferred polybutadiene PBs are those in which the ratio of the units of formula (I) in the total monomer units derived from 1,3-butadiene present in the polybutadiene is 50 to 65 mol percent, preferably 59 to 62 mol percent, the ratio of the units of formula (II) in the total monomer units derived from 1,3-butadiene present in the polybutadiene is 1 to 8 mol percent, preferably 2 to 6 mol percent, and the ratio of the units of formula (II) in the total monomer units derived from 1,3-butadiene present in the polybutadiene is 1 to 8 mol percent, preferably 2 to 6 mol percent. The proportion of units of formula (III) in the total of all monomer units is 25 to 40 mole percent, preferably 35 to 39 mole percent, provided that the total of all monomer units (I), (II), and (III) is 100 mole percent, and the polybutadiene has an average molecular weight of 1000 to 4000 g / mol, preferably 1200 to 3500 g / mol, preferably 1500 to 3000 g / mol, and a viscosity at 20° C. of preferably 2000 to 8000 mPa s, more preferably 3000 to 7000 mPa s.

[0038] The acoustic damping material contains at least one rubber LR that is liquid at 25° C. selected from the group consisting of polybutene that is liquid at 25° C. and polyisobutylene that is liquid at 25° C., preferably polyisobutylene that is liquid at 25° C., in an amount of 10% by weight or more based on the total weight of the acoustic damping material.

[0039] At amounts less than 10% by weight, the low temperature drop ball test performance is insufficient. This can be seen by comparing Ref.7 with E2 and E8.

[0040] The amount of the liquid rubber LR at 25°C is preferably 12.5-35% by weight, preferably 14-30% by weight, more preferably 15-25% by weight, and most preferably 15-20% by weight, based on the total weight of the sound damping material. This is advantageous in terms of good low temperature ball drop test performance, high adhesive strength, and cohesive failure pattern. This can be seen by comparing Ref.7 with E2 and E8.

[0041] The term "polybutene liquid at 25°C" preferably refers in this disclosure to olefin oligomers containing isobutylene and / or 1-butene and / or 2-butene, the proportions of their C4-olefin isomers may vary depending on the manufacturer and grade.

[0042] The term "polyisobutylene that is liquid at 25°C" preferably refers in this disclosure to polyolefins and olefin oligomers of isobutylene that preferably contain at least 75%, more preferably at least 85%, of repeat units derived from isobutylene.

[0043] Particularly suitable polybutenes and polyisobutylenes that are liquid at 25° C. have an average molecular weight of 5,000 g / mol or less, preferably 3,000 g / mol or less, more preferably 2,500 g / mol or less, even more preferably 2,000 g / mol or less, and still more preferably 1,500 g / mol or less.

[0044] Particularly suitable polybutenes and polyisobutylenes that are liquid at 25° C. have a polydispersity index (Mw / Mn) determined by gel permeation chromatography (GPC) of 7.5 or less, more preferably 5.0 or less, for example, in the range of 0.5 to 5.0, preferably 1.0 to 4.5, more preferably 1.0 to 3.5, and even more preferably 1.25 to 2.5.

[0045] Liquid polybutenes are commercially available, for example, under the trade names Indopol® H- and L-series (Ineos Oligomers), Infineum® C-series and Parapol® series (Infineum), and PB-series (Daelim).Liquid polyisobutylenes (PIBs) are commercially available, for example, under the trade names Glissopal® V-series (BASF), and Dynapak®-series (Univar GmbH, Germany).

[0046] The sound-damping material comprises at least 3% by weight of at least one butyl rubber BR, based on the total weight of the sound-damping material.

[0047] At amounts less than 3 wt.%, low temperature drop ball test performance is poor, which can be seen by comparing Ref.4 and Ref.6 with E2, E6, and E7.

[0048] Preferably, the amount of at least one butyl rubber BR is 4.5-15% by weight, preferably 5-12% by weight, preferably 5.5-10% by weight, most preferably 6-8% by weight, based on the total weight of the sound damping material. This is advantageous in terms of good low temperature ball drop test performance, high adhesive strength, and cohesive failure pattern. This can be seen by comparing Ref. 4-6 with E2 and E6-7.

[0049] The term "butyl rubber" as used herein refers to a rubber made up of a major portion of C4-C7 monoolefin monomers, preferably isoolefin monomers, and a minor portion, for example up to 30% by weight, of C4-C 14It refers to a polymer derived from a monomer mixture comprising a multiolefin monomer, preferably a conjugated diolefin. The preferred C4-C7 monoolefin monomer may be selected from the group consisting of isobutylene, 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene, 4-methyl-1-pentene, and mixtures thereof, preferably isobutylene.

[0050] Preferred C4~C 14 Multiolefins include C4 to C 10 Conjugated diolefins are preferred. 10 The conjugated diolefin may be selected from the group including isoprene, butadiene, 2,4-dimethylbutadiene, piperiline, 3-methyl-1,3-pentadiene, 2,4-hexadiene, 2-neopentyl-1,3-butadiene, 2-methyl-1,5-hexadiene, 2,5-dimethyl-2,4-hexadiene, 2-methyl-1,4-pentadiene, 2-methyl-1,6-heptadiene, cyclopentadiene, methylcyclopentadiene, cyclohexadiene, 1-vinyl-cyclohexadiene, and mixtures thereof, preferably isoprene.

[0051] Most preferably, the butyl rubber BR is a polymer derived from isobutylene and isoprene.

[0052] The at least one butyl rubber BR is preferably selected from the group consisting of butyl rubber and halogenated butyl rubber, preferably butyl rubber, chlorobutyl rubber and bromobutyl rubber, more preferably butyl rubber and bromobutyl rubber, most preferably bromobutyl rubber.

[0053] The preferred butyl rubber BR has a Mooney viscosity (ML1+8@125°C) of 10-60 MU (Mooney units), preferably 20-50 MU, preferably 25-40 MU. Preferably, the Mooney viscosity gives a measure of the viscosity of the rubber. It is defined as the shear torque resisting the rotation of a cylindrical metal disk (i.e. rotor) embedded in the rubber in a cylindrical cavity. The dimensions of the shear disk viscometer, the test temperature and the procedure for measuring the Mooney viscosity are specified in ASTM D1646.

[0054] The acoustic dampening material comprises at least 3% by weight, based on the total weight of the acoustic dampening material, of at least one natural or synthetic polyisoprene PI, preferably natural polyisoprene, and most preferably natural rubber.

[0055] At amounts less than 3 wt.%, low temperature drop ball test performance is poor, which can be seen by comparing Ref.4 and Ref.6 with E2, E6, and E7.

[0056] Preferably, the amount of at least one natural or synthetic polyisoprene PI is 4.5-15% by weight, preferably 5-12% by weight, preferably 5.5-10% by weight, most preferably 6-8% by weight, based on the total weight of the sound damping material. This is advantageous in terms of good low temperature ball drop test performance, high adhesive strength, and cohesive failure pattern. This can be seen by comparing Ref. 4-6 with E2 and E6-7.

[0057] The at least one natural or synthetic polyisoprene PI preferably has an average molecular weight of 100,000 g / mol or more, preferably 100,000 to 2,000,000 g / mol, more preferably 100,000 to 1,000,000 g / mol.

[0058] Natural rubber is a polymer of isoprene (methylbuta-1,3-diene), but is distinct from synthetic polyisoprene, which is the reaction product of metal-catalyzed reactions.

[0059] The natural or synthetic polyisoprene PI preferably has a Mooney viscosity (ML1+4) at 100° C. of 30 to 120, more preferably 40 to 65. The Mooney viscosity test referred to in this specification is in accordance with ASTM D-1646.

[0060] The acoustic dampening material comprises 4 to 15 weight percent of at least one hydrocarbon resin HR, based on the total weight of the acoustic dampening material.

[0061] The amount of the at least one hydrocarbon resin HR is preferably 5-12 wt%, more preferably 5.5-10 wt%, and most preferably 6.5-9.5 wt%, based on the total weight of the sound damping material. This is advantageous in terms of good low temperature ball drop test performance, high adhesive strength, and cohesive failure pattern. This can be seen by comparing Ref. 8-9 with E2 and E9.

[0062] The term "hydrocarbon resin" preferably refers herein to synthetic resins produced by polymerizing a mixture of unsaturated monomers obtained from petroleum-based feedstocks, such as natural liquefied gas, gas oil, or by-products of cracking petroleum naphtha. These types of hydrocarbon resins are also known as "petroleum resins" or "petroleum hydrocarbon resins". They also include pure monomeric aromatic resins, which are prepared by polymerizing aromatic monomer feedstocks that have been previously purified to remove color-causing contaminants and precisely control the product composition.

[0063] Examples of suitable hydrocarbon resins to be used as the at least one hydrocarbon resin HR include: C5 aliphatic resins, mixed C5 / C9 aliphatic / aromatic resins, aromatic modified C5 aliphatic resins, cycloaliphatic resins, mixed C5 aliphatic / cycloaliphatic resins, mixed C9 aromatic / cycloaliphatic resins, mixed C5 aliphatic / cycloaliphatic / C9 aromatic resins, aromatic modified cycloaliphatic resins, C9 aromatic resins, and also hydrogenated versions of the above mentioned resins. The designations "C5" and "C9" indicate that the monomers from which they are made are predominantly hydrocarbons having 4-6 and 8-10 carbon atoms, respectively. The term "hydrogenated" includes fully hydrogenated, substantially hydrogenated, and at least partially hydrogenated resins. Partially hydrogenated resins preferably have a hydrogenation level of, for example, 50%, 70%, or 90%.

[0064] The type of the at least one hydrocarbon resin HR is not particularly limited in the present invention. The selection of the at least one hydrocarbon resin HR depends, at least in part, on the type of other components contained in the binder matrix of the acoustic damping material, in particular on the type of the polymer component P.

[0065] The at least one hydrocarbon resin HR preferably has the following properties: a softening point, measured using the ring and ball method, according to the definition of the DIN EN 1238 standard, of at least 70°C, preferably at least 80°C, more preferably in the range of 70-180°C, preferably 80-150°C, more preferably 90-120°C, and / or preferably and; - an average molecular weight (M) in the range of 250 to 7500 g / mol, preferably 300 to 5000 g / mol; n ).

[0066] Suitable hydrocarbon resins are commercially available, for example, under the trade names Wingtack® series, Wingtack® Plus, Wingtack® Extra, and Wingtack® STS (all from Cray Valley); Escorez® 1000 series, Escorez® 2000 series, and Escorez® 5000 series (all from Exxon Mobil Chemical); Novares® T series, Novares® TT series, Novares® TD series, Novares® TL series, Novares® TN series, Novares® TK series, and Novares® TV series (all from RUETGERS Novares GmbH); and Kristalex®, Plastolyn®, Piccotex®, Piccolastic®, and Endex® (all from Eastman Chemicals).

[0067] The acoustic damping material includes e) at least one solid particulate filler FM, preferably at least one solid, particulate mineral filler FM.

[0068] It is preferred that the acoustic damping material comprises 5-75% by weight, preferably 15-70% by weight, more preferably 25-65% by weight, even more preferably 35-65% by weight, and still more preferably 40-65% by weight of at least one solid particle filler FM, based on the total weight of the acoustic damping material.

[0069] The at least one solid particle filler FM preferably has a diameter of d of 2.5 mm or less, more preferably 1.5 mm or less. 90 Preferably, the acoustically attenuating material is in the form of a solid particulate matter having a particle diameter d 90 The term "particles" refers to particles that are 90% by volume of all particles.90 The term "particle diameter" refers to a particle diameter having a diameter smaller than the value of the particle diameter in this disclosure. area ). The particle diameter distribution is preferably measured using a dynamic image analysis method, which is carried out according to the ISO 13322-2:2006 standard. To measure the particle diameter distribution, the particulate matter is preferably dispersed, preferably using a pneumatic dispersion method. The measurement can be carried out using various types of dynamic image analysis devices, for example the Camsizer XT device (trademark of Retsch Technology GmbH).

[0070] It is also preferred that the at least one solid particle filler FM is an inert mineral filler having a water-solubility at a temperature of 20° C. of less than 0.1 g / (100 g water), more preferably less than 0.05 g / (100 g water), even more preferably less than 0.01 g / (100 g water). The solubility of a compound in water can be measured as the saturation concentration at which adding more compound does not increase the concentration of the solution, i.e. the excess material begins to precipitate. The term “inert mineral filler” in the present disclosure refers to a mineral filler that, unlike a mineral binder, is not reactive, i.e. does not undergo hydration reactions in the presence of water.

[0071] In one or more embodiments, the at least one solid particle filler FM is selected from the group consisting of calcium carbonate, magnesium carbonate, calcium oxide, talc, kaolin, diatomaceous earth, wollastonite, feldspar, montmorillonite, dolomite, silica, preferably fumed silica, cristobalite, iron oxide, iron nickel oxide, strontium ferrite, barium-strontium ferrite, hollow ceramic spheres, hollow glass spheres, hollow organic spheres, glass spheres, mica, barium sulfate, and graphite.

[0072] The acoustic damping material may optionally contain additives commonly used in acoustic damping materials. Examples of suitable additives include, for example, pigments, thixotropic agents, heat stabilizers, drying agents, and flame retardants. If additives are used, they are preferably present in an amount of 25% by weight or less, more preferably 15% by weight or less, and even more preferably 10% by weight or less of the total weight of the acoustic damping material.

[0073] Preferred sound attenuating materials include: - 1 to 15% by weight, preferably 1.5 to 3% by weight, of at least one polybutadiene PB, based on the total weight of the sound-damping material; - 12.5 to 35% by weight, preferably 15 to 20% by weight, of rubber LR, liquid at 25°C, based on the total weight of the sound-damping material; - 4.5 to 15% by weight, preferably 6 to 8% by weight, of at least one natural or synthetic polyisoprene PI, based on the total weight of the sound-damping material; - 4.5 to 15% by weight, preferably 6 to 8% by weight, of at least one butyl rubber BR, based on the total weight of the sound-damping material; - 5 to 12% by weight, preferably 5.5 to 10% by weight, most preferably 6.5 to 9.5% by weight, of at least one hydrocarbon resin HR, based on the total weight of the acoustic damping material; and - 5-75 wt.-%, preferably 40-65 wt.-%, of at least one solid particle filler FM, based on the total weight of the sound-damping material.

[0074] Another subject of the invention is a process for producing an acoustic damping material according to the invention, which process comprises mixing components a) to f) with one another at elevated temperature, preferably at a temperature in the range from 120 to 200°C, more preferably from 130 to 180°C, until a homogeneously mixed mixture is obtained.

[0075] The term "uniformly mixed mixture" as used herein refers to a composition in which the individual components are substantially uniformly distributed throughout the composition. Moreover, the uniformly mixed mixture is preferably a multiphase mixture. As will be apparent to those skilled in the art, within such a mixed composition, regions may form in which the concentration of one of the components is slightly higher than in other regions, but 100% uniform distribution of all of the components is generally not achievable. However, in the present invention, such a mixed composition having an "incomplete" distribution of the components is also included in the term "uniformly mixed mixture".

[0076] Various types of conventional mixing equipment can be used to mix the components a) to f) together. The mixing step can be carried out as a batch process using a batch type mixer, such as a Brabender mixer, a Banbury mixer, a roll mixer, or as a continuous process using a continuous type mixer, such as an extruder, in particular a single screw or twin screw extruder.

[0077] The homogeneously mixed mixture obtained in the mixing step is then cooled to a temperature below 100°C, more preferably below 80°C. If an extruder device is used in the mixing step, the homogeneously mixed mixture is preferably extruded through an extruder die prior to the cooling step. The cooled homogeneously mixed mixture is storage stable under normal storage conditions. The term "storage stable" in the present disclosure refers to a material that can be stored for an extended period of time, for example at least one month, particularly at least three months, under specific storage conditions without any significant change in the application performance of the material. The term "typical storage conditions" refers to a temperature below 60°C, particularly below 50°C.

[0078] The homogeneously mixed mixture can be further processed into the form of a shaped article, such as a sheet or film, by using conventional techniques, such as extrusion, calendering, hot pressing techniques. The forming step is preferably carried out before the cooling step. In one or more embodiments, the homogeneously mixed mixture is extruded through a flat die to form a sheet of film, which is preferably cooled between a pair of calendering cooling rolls. Molded articles having specific dimensions can be made from the extruded sheet of film, for example, by punching or die cutting.

[0079] Another subject of the invention is the use of an acoustic damping material according to the invention for damping vibrations and / or noise in transport vehicles or white goods.

[0080] Another subject of the invention is a vibration and noise damping element (1) comprising: i) a damping layer (2) having first and second surfaces (3, 3'); and ii) an adhesive layer (4) covering at least a portion of the first surface (3) of the damping layer (2), wherein the adhesive layer (4) comprises or consists of the acoustic damping material of the present invention.

[0081] A cross-sectional view of a vibration and noise damping element according to the invention is shown in FIG.

[0082] In one or more embodiments, the damping layer is a sheet-like element having first and second major surfaces defining a thickness therebetween and having a length and width at least 5 times, preferably at least 15 times, more preferably at least 25 times the thickness of the sheet-like element. The term "thickness" preferably refers to a dimension of the sheet-like element measured in a plane perpendicular to the length and width dimensions of the element. In embodiments in which the damping layer is a sheet-like element, the first and second surfaces of the damping layer correspond to the first and second major surfaces of the sheet-like element.

[0083] The damping layer and the adhesive layer are preferably directly connected to each other at their opposing surfaces. The expression "directly connected" is to be understood in the context of the present invention to mean that there are no further layers or materials between the two layers and that the opposing surfaces of the layers are directly attached to each other. In one or more embodiments, the adhesive layer covers at least 50%, preferably at least 65%, more preferably at least 75% of the first surface of the damping layer. In one or more further embodiments, the adhesive layer covers substantially the entire area of ​​the first surface of the damping layer. The expression "substantially the entire area" is to be understood to mean at least 90%, preferably at least 95%, more preferably at least 98.5% of the total area.

[0084] Preferably, the damping layer comprises components selected from the list: a bitumen component B, a thermoplastic polymer component P, and a rubber component Ru, preferably a rubber component Ru.

[0085] A preferred rubber component Ru is selected from the list of rubbers LR which are liquid at 25° C. and selected from the group consisting of polybutene which is liquid at 25° C. and polyisobutylene which is liquid at 25° C., butyl rubber BR, natural or synthetic polyisoprene PI, nitrile rubber NBR, ethylene-propylene terpolymer EPDM, ethylene-propylene copolymer EPM, and chloroprene rubber CR, and is preferably selected from the list of rubbers LR which are liquid at 25° C. and selected from the group consisting of polybutene which is liquid at 25° C. and polyisobutylene which is liquid at 25° C., butyl rubber BR, and natural or synthetic polyisoprene PI.

[0086] The bituminous component B may include one or more different types of bituminous materials, such as, for example, penetration grade (distillate) bitumen, air rectified (semi-blown) bitumen, and hard grade bitumen.

[0087] The term "bitumen" in this disclosure refers to heavy hydrocarbon blends having a solid consistency at room temperature. They are usually obtained as vacuum distillation residues from the distillation (topping or vacuum distillation) and / or refinery processes, which may be secondary processing processes, such as pyrolysis and visbreaking, of suitable crude oils. Furthermore, the term "bitumen" further refers to natural and synthetic bitumens, as well as bituminous materials obtained from the extraction of tar and bituminous sands.

[0088] The term "penetration grade bitumen" as used herein refers to bitumen obtained from the "fractional distillation" of crude oil. The heavy fraction (also called long residue) consisting of high molecular weight hydrocarbons, obtained after removing the gasoline, kerosene, and diesel fractions, is first distilled in a vacuum distillation column to obtain additional diesel, distillates, and short residues. The short residues are then used as feedstock to produce various grades of bitumen, typically classified by their penetration index, defined as the PEN value, which is the distance (in 0.1 millimeter (dmm) increments) that a needle will penetrate into the bitumen under standard test methods. Penetration grade bitumen is characterized by its penetration and softening point. The term "air-rectified bitumen" or "air-refined bitumen" refers to bitumen that has been subjected to mild oxidation with the goal of producing a bitumen that meets pavement-grade bitumen specifications. The term "hard grade bitumen" refers to bitumen produced from propane-precipitated bitumen using extended vacuum distillation with some air rectification. Hard bitumen typically has low penetration values ​​and high softening points.

[0089] In one or more embodiments, the bituminous component B comprises at least 75% by weight, preferably at least 85% by weight, more preferably at least 90% by weight, of at least one penetration grade bitumen, preferably having a penetration value in the range of 15-50 dmm, more preferably 20-45 dmm, and / or a softening point in the range of 40-125°C, preferably 50-100°C, measured by ring and ball measurement performed according to the DIN EN 1238 standard.

[0090] A suitable thermoplastic polymer component P is selected so that the temperature range in which the maximum vibration damping effect of the acoustic damping material occurs corresponds to the temperature range in which the surface of the substrate to be damped against vibrations will be subjected during its use. Since the ability of a polymer to dissipate vibrations into thermal energy is maximized when the polymer is in a transition state between a hard / glassy and a soft / rubbery state, a suitable thermoplastic polymer P for use in the acoustic damping material will have a glass transition temperature (T g For example, when the sound damping material is used for vibration and noise damping in automobile structures, the application temperature is typically in the range of −40° C. to 60° C., in particular −35° C. to 50° C. On the other hand, the preferred thermoplastic polymers P used in the sound damping material have a softening point (T s ) and / or melting temperature (T m )

[0091] In one or more embodiments, the thermoplastic polymer P has the following properties: - A glass transition temperature (T) measured as the peak of the loss modulus (G") curve by dynamic mechanical analysis (DMA) using an applied frequency of 1 Hz and a strain level of 0.1%, below 25°C, preferably below 5°C, more preferably below 0°C. g ), and / or - a softening point (T) determined according to the ring and ball method carried out according to the DIN EN 1238 standard, higher than 35°C, preferably higher than 45°C, more preferably higher than 55°C, for example in the range from 35 to 250°C, preferably from 45 to 200°C, more preferably from 55 to 180°C. s ).

[0092] There is no particular restriction on the type of thermoplastic polymer P. Various types of thermoplastic polymers, including crystalline, semi-crystalline and amorphous polymers as well as thermoplastic elastomers, are suitable for use as the at least one thermoplastic polymer P. Suitable thermoplastic polymers P include, in particular, polyolefin homopolymers and copolymers, copolymers of ethylene and vinyl acetate, and thermoplastic olefin elastomers (TPE-O).

[0093] More preferably, the damping layer comprises: 10 to 18% by weight, based on the total weight of the damping layer, of at least one rubber LR that is liquid at 25°C selected from the group consisting of polybutene that is liquid at 25°C and polyisobutylene that is liquid at 25°C, preferably polyisobutylene that is liquid at 25°C; 2 to 5% by weight, based on the total weight of the damping layer, of at least one butyl rubber BR; 0.5-3 wt. %, based on the total weight of the damping layer, of at least one natural or synthetic polyisoprene PI, preferably natural polyisoprene, most preferably natural rubber; 5-10% by weight, based on the total weight of the damping layer, of at least one hydrocarbon resin HR; 50-80 wt. % of at least one solid particle filler FM, based on the total weight of the damping layer.

[0094] The rubber LR which is liquid at 25°C selected from the group consisting of polybutene which is liquid at 25°C and polyisobutylene which is liquid at 25°C, butyl rubber BR, natural or synthetic polyisoprene PI, hydrocarbon resin HR, and solid particle filler FM have previously been considered as preferred compositions for the sound damping material.

[0095] In one or more embodiments, the damping layer has a maximum thickness in the range of 0.5 to 10 mm, preferably 0.5 to 7 mm, more preferably 0.5 to 5 mm, and even more preferably 0.5 to 3 mm; and / or a density of 1 to 4 g / cm 3 , preferably 1 to 3 g / cm 3 , more preferably 1 to 2 g / cm 3 and / or 1-5 kg / m 2 , preferably 1 to 4.5 kg / m 2 , more preferably 1.5 to 4.5 kg / m 2 , and more preferably 1.5 to 3.5 kg / m 2 It has a mass per unit area of

[0096] The adhesive layer 4 comprises, or preferably consists of, the acoustic damping material of the present invention. The preferred embodiments for the acoustic damping material described above also apply to the acoustic damping material in the adhesive layer 4.

[0097] In one or more embodiments, the adhesive layer has a maximum thickness in the range of 0.5 to 5 mm, preferably 0.5 to 3 mm, more preferably 0.5 to 2 mm, and even more preferably 0.5 to 1 mm; and / or a density of 1 to 4 g / cm 3 , preferably 1 to 3 g / cm 3 , more preferably 1 to 2 g / cm 3 and / or 0.5-5 kg / m 2 , preferably 0.6 to 4 kg / m 2 , more preferably 0.7 to 3 kg / m 2 It has a mass per unit area of

[0098] Preferred sizes for the vibration and noise dampening elements are elements with a length and width of 20-1000mm, more preferably 50-500mm, most preferably 100-400mm.

[0099] Preferably, the vibration and noise damping element has the following properties: - Temperature at which the maximum loss factor is measured (T@LF max ) is between 5°C and 25°C, preferably between 15°C and 25°C. - Maximum Loss Factor (LF max ) is 0.3 or more, preferably 0.35 or more, preferably 0.39 or more, preferably 0.40 or more, and most preferably 0.41 or more.

[0100] The loss factor is preferably determined using the measurement method specified in the ISO 6721 standard, more preferably using the measurement method described in the experimental section.

[0101] In one or more embodiments, the vibration and noise damping element further includes, in addition to the damping layer and the adhesive layer, a constraining layer covering at least a portion of the second surface of the damping layer. The vibration and noise damping element in these embodiments is generally referred to as a "constrained layer damper." The damping layer and the constraining layer are preferably directly bonded to each other at their opposing surfaces, and the damping layer is preferably sandwiched between the adhesive layer and the constraining layer. In one or more embodiments, the constraining layer substantially, preferably completely, covers the entire area of ​​the second surface of the damping layer. A cross-sectional view of a vibration and noise damping element according to these embodiments is shown in FIG. 2.

[0102] In one or more embodiments, the constraining layer is a metal sheet, preferably an aluminum or steel sheet, or a polymer sheet, preferably a glass fiber reinforced polymer sheet. There is no particular limit to the thickness of the constraining layer, but it is generally preferred to use a constraining layer that is thinner than the damping layer. The preferred thickness also depends on the material of the constraining layer. In one or more embodiments, the constraining layer has a thickness of 0.05 to 1.5 mm, preferably 0.1 to 1.25 mm, more preferably 0.1 to 1.0 mm. In one or more embodiments, the constraining layer is a metal sheet having a thickness of 0.05 to 0.5 mm, preferably 0.05 to 0.4 mm. In one or more further embodiments, the constraining layer is a polymer sheet having a thickness of 0.1 to 1.2 mm, preferably 0.25 to 1.0 mm.

[0103] It is preferred that the constraining layer has a modulus of elasticity that is higher than the modulus of elasticity of the damping layer, for example at least three times, preferably at least five times, more preferably at least ten times, where the modulus of elasticity is measured using the method specified in the ISO 6892-1:2016 standard (for metal sheets) or the ISO 527-2 standard (for polymer sheets).

[0104] In a preferred embodiment, the vibration and noise damping element comprises a damping layer, an adhesive layer, and a constraining layer.

[0105] Another subject of the invention is a method for manufacturing an inventive vibration and noise damping element, which method comprises the following steps: i) providing a damping layer having first and second surfaces; ii) applying onto a first surface of the damping layer an adhesive composition comprising or consisting of the acoustic damping material of the present invention.

[0106] Step i) can be carried out by a variety of conventional techniques known to those skilled in the art. For example, the acoustic damping material can be first melt processed in an extruder apparatus and then extruded through an extruder die, preferably a flat die, into the shape of the damping layer. Alternatively, the acoustic damping material of the present invention can be processed into a damping layer using a calendaring or hot pressing process.

[0107] Step ii) can be carried out by various conventional techniques known to those skilled in the art. Various conventional techniques can be used to apply the adhesive composition onto the surface of the damping layer. For example, the adhesive composition can be applied onto the surface of the sheet by nozzle extrusion, powder dispersion, calendaring or spray lamination, preferably by calendaring.

[0108] Another subject of the invention is a method for applying a vibration and noise damping element according to the invention to a noise-generating surface of a substrate, said method comprising the following steps: I) providing a vibration and noise damping element according to the invention, II) contacting an outer major surface of the adhesive layer of the vibration and noise damping element with the noise generating surface and applying sufficient pressure to form an adhesive bond; or II') heating the adhesive layer and / or the substrate, contacting an outer major surface of the adhesive layer with the noise producing surface, and allowing the adhesive layer to cool thereby forming an adhesive bond.

[0109] The term "outer main surface" of the adhesive layer refers to the main surface of the adhesive layer on the side opposite to the side of the damping layer. The substrate with the noise-generating surface may be various types of molded articles, such as, for example, panels, sheets, or films, made of, for example, metal, plastic, or fiber-reinforced plastic. Heating of the adhesive layer and / or substrate in step II') can be carried out in various conventional ways, such as, for example, heating in an oven, heating by air flow, or heating with infrared (IR) radiation.

[0110] Yet another subject of the invention is a vibration-damped system comprising a substrate (6) having a noise-generating surface (7) and a vibration and noise damping element (1) according to the invention, in which at least a part of the first surface (3) of the damping layer (2) is adhesively bonded to the noise-generating surface (7) via an adhesive layer (4). A cross-sectional view of the vibration-damped system is shown in FIG.

[0111] In one or more embodiments, the vibration and noise damping element (1) is a constrained damping element including a constraining layer (5), where the damping layer (2) is sandwiched between an adhesive layer (4) and a constraining layer (5). A cross-sectional view of a vibration damped system according to this embodiment is shown in Figure 4.

[0112] In one or more embodiments, the substrate having a noise-generating surface is part of the structure of an automotive vehicle or white goods. EXAMPLES

[0113] The ingredients shown in Table 1 were used in the compositions for the adhesive layers shown in Tables 3 and 4, respectively, and for the damping layers shown in Table 2.

[0114] [Table 1]

[0115] Preparation of the Composition The acoustic damping materials of the invention used in the adhesive layer and shown in Tables 3 and 4, Examples Ex-1 to Ex-6, as well as Reference Examples Ref. 1 to Ref. 9, were prepared according to the following procedure.

[0116] In the first step, the components BR, PI, HR, and half of the calcite were mixed in a batch type mixer. The remaining ingredients were then added at a constant rate over a period of one hour and mixed for 20 minutes. The mixed composition was then stored in an unsealed drum and used immediately after mixing.

[0117] In a second step, the components for the damping layer composition were mixed with the following components shown in Table 2:

[0118] [Table 2]

[0119] The BR, PI, HR, and half of the calcite were mixed in a batch type mixer. The remaining ingredients were then added at a constant rate over a period of one hour and mixed for 20 minutes. The mixed damping layer composition was then stored in an unsealed drum and used immediately after mixing.

[0120] For the following tests, test samples (vibration and noise damping elements) were prepared with a 0.6 mm thick adhesive layer of compositions Ex-1 to Ex-6 and reference examples Ref.1 to Ref.9, respectively. On top of this adhesive layer was added a 1.1 mm thick damping layer of the above mentioned damping layer composition. On top of the damping layer was added a 0.3 mm thick aluminum layer (constraining layer). The test results are shown in Tables 3 and 4.

[0121] Measurement of high temperature resistance ("ht resistance") Heat resistance tests at 210°C were carried out according to BMW Group standard: Adhesives and sealing materials used in the body shop. Damping pad, Requirements and testing, GS 97028-16:2012-02, page 4, Table 1: Resistance to high temperature ("Waermetest"), AA-0415, Edition 2018-10. The test samples had a length x width of 16 cm x 7 cm.

[0122] Grading system: To get a rating of OK, there must be no blistering, no melting, no slippage, and no shrinkage.

[0123] Measurement / quantification of adhesion at low temperatures by a drop ball test at -30°C ("Bdt-30°C") The ball drop test at -30°C was carried out according to the Volkswagen Group standard: quality requirements, self-adhesive stiffening pads and sound deadening pads, QP M052, page 12, point 3.7.5, Ball drop test / determination of cold adhesion ("Kugelfall / Bestimmung der Kaerltehaftung"), PV 3971, edition 2020-03. The length x width of the test samples was 7 cm x 7 cm.

[0124] Evaluation method: Rating 1: No cracking or splintering of the test specimen, no chipping of the test sheet Rating 2: Cracking or splintering of the test specimen, but no chipping of the test sheet Rating 3: There is no chipping from the test sheet, but even a slight bending load may cause the test specimen to delaminate from the test sheet. Rating 4: Cracking or splintering of the test specimen, partial chipping from the test sheet Rating 5: Cracking or splintering of the test specimen, large chipping from the test sheet Rating 6: Complete delamination from the test sheet.

[0125] Adhesion / peel strength measurements ("peel strength") The peel strength tests were carried out according to BMW Group standards: Adhesives and sealing materials used in the body shop. Damping pad, Requirements and testing, GS 97028-16:2012-02, page 4, Table 1: Adhesion ("Peel-resistance of sound deadening and stiffening matgerials in the body shop"), AA-0007, 2018-10 edition. The test samples had a length x width of 20 cm x 3 cm. In addition, the failure patterns were visually checked.

[0126] Evaluation method: - On oiled steel plate, after 30 minutes, at room temperature: >1.5N / cm - On oiled steel plate, after 30 minutes, 195℃:>4N / cm

[0127] Measurement of loss factor ("loss factor") The loss factor of the test specimens was measured using the measurement method specified in the ISO 6721 standard. The measurements were performed using a commercially available loss factor tester at the anti-resonance point of 200 Hz and in the temperature range of 20 to 60° C. The length and width of the test samples were 20 cm x 1 cm.

[0128] It is advantageous if the maximum values ​​of the loss factors in Tables 1 and 2 are measured at 10°C or 20°C, preferably at 20°C, since this is the most common operating temperature in vehicles.

[0129] [Table 3]

[0130] [Table 4]

Claims

1. An acoustic attenuation material, comprising: a) at least one polybutadiene PB containing monomer units derived from 1,3-butadiene of 0.75 wt% or more based on the total weight of the acoustic attenuation material, 【Chemical 1】 [wherein the ratio of the monomer units of formula (I) in the total monomer units derived from 1,3-butadiene present in the polybutadiene is 25 to 75 mol%, the ratio of the units of formula (II) in the total monomer units derived from 1,3-butadiene present in the polybutadiene is 0 to 10 mol%, and the ratio of the monomer units of formula (III) in the total monomer units derived from 1,3-butadiene present in the polybutadiene is 25 to 75 mol%, wherein the total of the monomer units (I), (II), and (III) is 100 mol%, and the polybutadiene preferably has an average molecular weight of 1000 to 4000 g / mol]; b) at least one rubber LR that is liquid at 25°C, selected from the group consisting of polybutene that is liquid at 25°C and polyisobutylene that is liquid at 25°C, preferably polyisobutylene that is liquid at 25°C, of 10 wt% or more based on the total weight of the acoustic attenuation material; c) at least one butyl rubber BR of 3 wt% or more based on the total weight of the acoustic attenuation material; d) at least one natural or synthetic polyisoprene PI, preferably natural polyisoprene, most preferably natural rubber, of 3 wt% or more based on the total weight of the acoustic attenuation material; e) at least one hydrocarbon resin HR of 4 to 15 wt% based on the total weight of the acoustic attenuation material; f) at least one solid particle filler FM; An acoustic attenuation material containing the above components.

2. In the at least one polybutadiene PB, the ratio of the units of the formula (I) in the total monomer units derived from 1,3-butadiene present in the polybutadiene is 50 to 65 mol%, preferably 59 to 62 mol%; the ratio of the units of the formula (II) in the total monomer units derived from 1,3-butadiene present in the polybutadiene is 1 to 8 mol%, preferably 2 to 6 mol%; and the ratio of the units of the formula (III) in the total monomer units derived from 1,3-butadiene present in the polybutadiene is 25 to 40 mol%, preferably 35 to 39 mol%, provided that the total of all the monomer units (I), (II), and (III) is 100 mol%, and the polybutadiene has an average molecular weight of 1200 to 3500 g / mol, preferably 1500 to 3000 g / mol. The acoustic attenuation material according to claim 1.

3. The amount of the at least one polybutadiene PB is 1 to 15 wt%, preferably 1.2 to 10 wt%, preferably 1.3 to 8 wt%, preferably 1.5 to 7 wt%, preferably 1.5 to 5 wt%, most preferably 1.5 to 3 wt% based on the total weight of the acoustic attenuation material. The acoustic attenuation material according to claim 1 or 2.

4. The amount of the rubber LR that is liquid at 25°C is 12.5 to 35 wt%, preferably 14 to 30 wt%, preferably 15 to 25 wt%, most preferably 15 to 20 wt% based on the total weight of the acoustic attenuation material. The acoustic attenuation material according to claim 1 or 2.

5. The amount of the at least one natural or synthetic polyisoprene PI is 4.5 to 15 wt%, preferably 5 to 12 wt%, preferably 5.5 to 10 wt%, most preferably 6 to 8 wt% based on the total weight of the acoustic attenuation material. The acoustic attenuation material according to claim 1 or 2.

6. The amount of the at least one butyl rubber BR is 4.5 to 15 wt%, preferably 5 to 12 wt%, preferably 5.5 to 10 wt%, most preferably 6 to 8 wt% based on the total weight of the acoustic attenuation material. The acoustic attenuation material according to claim 1 or 2.

7. The amount of the at least one hydrocarbon resin HR is 5 to 12% by weight, preferably 5.5 to 10% by weight, and most preferably 6.5 to 9.5% by weight based on the total weight of the acoustic attenuation material, according to the acoustic attenuation material of claim 1 or 2.

8. The at least one rubber LR that is liquid at 25°C has an average molecular weight of 5,000 g / mol or less, preferably 3,000 g / mol or less, more preferably 2,500 g / mol or less, even more preferably 2,000 g / mol or less, and still more preferably 1,500 g / mol or less, according to the acoustic attenuation material of claim 1 or 2.

9. The at least one butyl rubber BR has a Mooney viscosity (ML1+8@125°C) of 10 to 60 MU (Mooney unit), preferably 20 to 50 MU, preferably 25 to 40 MU, according to the acoustic attenuation material of claim 1 or 2, preferably in accordance with ASTM D1646.

10. The at least one natural or synthetic polyisoprene PI has a Mooney viscosity (ML1+4) at 100°C of 30 to 120, more preferably 40 to 65, according to the acoustic attenuation material of claim 1 or 2, preferably in accordance with ASTM D1646.

11. Use of the acoustic attenuation material according to claim 1 or 2, for attenuating vibration and / or noise in a transport vehicle or a white goods appliance.

12. An element (1) for attenuating vibration and noise, i) a damping layer (2) having a first surface (3) and a second surface (3'), and ii) an adhesive layer (4) covering at least a part of the first surface (3) of the damping layer (2), the adhesive layer (4) containing the acoustic attenuation material according to claim 1 or consisting of the acoustic attenuation material according to claim 1. An element (1) for attenuating vibration and noise, including the above.

13. The adhesive layer (4) has a thickness of 0.5 to 5 mm, preferably 0.5 to 3 mm, more preferably 0.5 to 2 mm, even more preferably 0.5 to 1 mm, and / or 0.5 to 5 kg / m ２ , preferably 0.6 to 4 kg / m ２ , more preferably 0.7 to 3 kg / m ２ per unit area, and the vibration and noise damping element (1) according to claim 12.

14. A method for applying the vibration and noise attenuation element (1) according to claim 12 or 13 to a noise-generating surface (7) of a substrate (6), the method comprising: I) a step of providing the vibration and noise attenuation element (1) according to claim 12 or 13; II) contacting the outer main surface of the adhesive layer (4) of the vibration and noise attenuation element (1) with the noise-generating surface (7) and applying sufficient pressure to form an adhesive bond, or II') heating the adhesive layer (4) and / or the substrate (6), bringing the outer main surface of the adhesive layer (4) into contact with the noise-generating surface (7), and cooling the adhesive layer (4) to form an adhesive bond; A method comprising the above. **Claim 15** A vibration-damped system comprising a substrate (6) having a noise-generating surface (7) and a vibration and noise attenuation element (1) according to claim 12 or 13, wherein at least a part of the first surface (3) of the damping layer (2) is adhesively bonded to the noise-generating surface (7) via the adhesive layer (4), and the substrate (6) having the noise-generating surface (7) is preferably part of a structure of a motor vehicle or a white goods appliance.

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